48th Annual Meeting of the International Society for Pediatric Neurosurgery

ISPN 2022 Meeting Chair: Wan Tew Seow

ISPN 2022 President: Frederick Boop

ISPN 2022 Scientific Chair: Abhaya Kulkarni

ISPN 2022 Scientific Co-Chair: Benedetta Pettorini

Platform Presentation Abstracts

PF-001

Neuroendoscopy

Prediction of 6 months endoscopic third ventriculostomy success rate in patients with hydrocephalus using a multi-layer perceptron network

Mohammad Sadegh Masoudi¹, Elahe Rezaeia², Amirhossein Tahmouresic³, Sousan Taleghani⁴, Reza Taheri⁵

¹Department of Neurosurgery, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

²School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

³Kerman University of Medical Sciences, Machine Learning Expert, Kerman, Iran

⁴Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran

⁵Department of Neurosurgery, Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

BACKGROUND AND AIM: Discrimination Between Patients Most Likely to Benefit From Endoscopic Third Ventriculostomy (ETV) and Those at Higher Risk of Failure Is Challenging. Compared to Other Standard Models, We Have Tried to Develop a Prognostic Multi-Layer Perceptron Model Based On Potentially High-Impact New Variables for Predicting the ETV Success Score (ETVSS).

METHOD: Clinical and Radiological Data of 128 Patients Have Been Collected, and ETV Outcomes Were Evaluated. The Success of ETV Was Defined As Remission of Symptoms and Not Requiring VPS for Six Months After Surgery. Several Clinical and Radiological Features Have Been Used to Construct the Model. Then the Binary Gravitational Search Algorithm Was Applied to Extract the Best Set of Features. Finally, Two Models Were Created Based On These Features, Multi-Layer Perceptron, and Logistic Regression.

RESULTS: Eight variables have been selected (age, callosal angle, bifrontal angle, bicaudate index, subdural hygroma, temporal horn width, third ventricle width, frontal horn width). The neural network model was constructed upon the selected features. The result was AUC:0.913 and accuracy:0.859. Then the BGSA algorithm removed half of the features, and the remaining (Age, Temporal horn width, Bifrontal angle, Frontal horn width) were applied to construct models. The ANN could reach an accuracy of 0.84, AUC:0.858 and Positive Predictive Value (PPV): 0.92, which was higher than the logistic regression model (accuracy:0.80, AUC: 0.819, PPV: 0.89).

CONCLUSIONS: The research findings have shown that the MLP model is more effective than the classic logistic regression tools in predicting ETV success rate. In this model, two newly added features, the width of the lateral ventricle's temporal horn and the lateral ventricle's frontal horn, yield a relatively high inter-observer reliability.

Keywords: Hydrocephalus, Endoscopic Third Ventriculostomy, Multi-layer Perceptron Network

PF-002

Neuro-Oncology

Characterization of the BBB in DIPG murine models and effect of ultrasound on its specificities and permeability to AsiDNA™

Adam Biard¹, Ludivine Le Dret¹, Marie Dutreix², Alexandre Carpentier³, Manon Lancien¹, Alexandre Plessier¹, Yassine Ajlil¹, Marie Anne Debily¹, David Castel¹, Jacques Grill¹, Kevin Beccaria⁴

¹U981—INSERM UMR 981 « Prédicteurs moléculaires et nouvelles cibles en oncologie»—Équipe « Génomique et oncogenèse des tumeurs cérébrales pédiatriques», Gustave Roussy, Villejuif, France

²Institut Curie, PSL Research University, CNRS UMR 3347, INSERM U1021, Orsay, Paris, France

³Department of neurosurgery, Pitié Salpétrière Hospital, Sorbonnes University, Paris, France

⁴Department of pediatric neurosurgery, Necker Enfants Malades Hospital, Paris Cité University, Paris, France

BACKGROUND AND AIM: The poor prognosis of pediatric diffuse midline gliomas, including diffuse intrinsic pontine gliomas (DIPGs), is partly due to the blood–brain barrier (BBB). The BBB can be opened by ultrasound (US), but few studies have focused on its characteristics in DIPGs, especially when submitted to US. We aimed to characterize the BBB in DIPGs and the influence of US on its characteristics, and to evaluate the effect of US-induced BBB opening on the kinetics of AsiDNA™ in DIPG murine models.

METHOD: US-induced BBB opening was performed with the SonoCloud® device and controlled with Evans blue dye. Permeability of DIPGs’ BBB was assessed with fluorescent dextrans. A histological evaluation of BBB markers was carried out by immunohistochemistry and immunofluorescence, including endothelial markers (CD34, GLUT1, PLAVP), tight junctions proteins (claudin 5, Zona occludens 1), and the efflux transporter ABCB1. An in vivo and ex vivo kinetic study of AsiDNA™ was performed with fluorescence.

RESULTS: We could repeatedly open the BBB with low intensity US (acoustic pressure 0.4 Mpa). In vivo, 3 kDa and 70 kDa dextrans delivery to DIPG tissue was increased by US-induced opening of the BBB, while 500 kDa dextrans did not cross the BBB spontaneously or after US. ABCB1 gene expression was variable at baseline in different DIPGs but was downregulated after US-induced BBB opening. The spontaneous passage of AsiDNA™ through the BBB was limited but could be increased after US-induced BBB opening.

CONCLUSIONS: We have shown that the BBB was specific in DIPG murine models, particularly in the expression of ABCB1. This BBB can be modulated and permeabilized by US, a technique that could allow for an improved delivery of AsiDNA. This study is a preliminary step before the introduction of a such technique and treatment in future clinical trials in children and adolescents with DMGs.

Keywords: DIPG, Blood Brain Barrier, Pediatric, Glioma, Ultrasound

PF-003

Neuro-Oncology

Results of a Phase Ib Trial of Recombinant Polio:rhinovirus Immunotherapy for Recurrent Pediatric High Grade Glioma

Eric M Thompson¹, Daniel Landi², Matthias Gromeier¹, Michael Brown¹, Henry Friedman¹, Roger Mclendon³, Dani Bolognesi⁴, Kristin Schroeder², Oren Becher⁵, Allan Friedman¹, Ashley Walter⁶, Stevie Threatt⁶, Denise Jaggers⁶, Annick Desjardins¹, Darell Bigner¹, David Ashley¹

¹Department of Neurological Surgery, Duke University, Durham, USA

²Department of Pediatrics, Duke University, Durham, USA

³Department of Pathology, Duke University, Durham, USA

⁴Department of Surgery, Duke University, Durham, USA

⁵Department of Pediatrics, Mount Sinai Health System, New York, USA

⁶Preston Robert Tisch Brain Tumor Center, Duke University, Durham, USA

BACKGROUND AND AIM: Outcomes of recurrent pediatric high grade glioma (pHHG) are poor with a median overall survival (OS) of less than 6 months. Viral immunotherapy such as the polio:rhinovirus chimera, PVSRIPO, is a novel approach for treatment of recurrent pHHG. PVSRIPO is genetically engineered to prevent neurovirulence. In adults with recurrent glioblastoma treated with PVSRIPO, 21% survived at least 36 months. The poliovirus receptor, CD155, is ubiquitously expressed in malignant pediatric brain tumors and is a target in pHHG.

METHOD: The primary objective of this Phase 1b clinical trial was to evaluate the safety and feasibility of PVSRIPO for recurrent pHGG. PVSRIPO was given at a single dose, 5 × 107 50% tissue-culture infectious dose (TCID50) administered by convection enhanced delivery (CED) to children with biopsy-confirmed recurrent pHHG between ≥ 1 and ≤ 5.5 in diameter. 3 mL of PVSRIPO was delivered at 0.5 mL/hr via a single catheter.

RESULTS: Eight patients were treated with PVSRIPO. Five males and 3 females with a median age of 16.5 (range 9–19) were enrolled. Six patients had recurrent glioblastoma, 2 had recurrent anaplastic astrocytoma. The median number of previous recurrences prior to enrollment was 3.5 (range 1–5). Four patients received bevacizumab on-study for treatment-related peritumoral inflammation/edema. Six of 8 patients experienced 26 treatment related adverse events (AEs) possibly, probably, or definitely related to protocol treatment. There were no Grade 4 or 5 AEs. There were 3 Grade 3 AEs: 2 headaches and 1 seizure. There were no AEs related to biopsy or CED catheter insertion/removal. Median OS was 4.13 months (range 1.23-NA). One patient is currently alive at > 20 months.

CONCLUSIONS: CED of PVSPRIO is both safe and feasible for the treatment of recurrent pHHG. Updated immune monitoring and histologic correlative results will also be presented.

Keywords: Oncolytic virus, Convection enhanced delivery, High grade glioma, Viral immunotherapy, Clinical trial

PF-004

Neuro-Oncology

Treating the “Untreatable”: Enhancing CAR T-Cell Therapy for Paediatric High-Grade Glioma

Louise Frances Steele Saukila¹, Matteo Righi², Alice Piapi¹, Manav Pathania³, Alastair Hotblack¹, Karin Straathof¹

¹UCL Cancer Institute, London, UK; UCL Great Ormond Street Institute of Child Health, London, UK

²UCL Cancer Institute, London, UK

³Cambridge University, Cambridge, UK

BACKGROUND AND AIM: Diffuse midline glioma (DMG) carries a devastating prognosis, with therapies limited by anatomical location and chemoresistance, and palliative radiotherapy the mainstay of treatment. Chimeric antigen receptor (CAR) T-cell therapy has shown promising pre-clinical results in treating these infiltrative tumours whilst leaving interspersed normal brain cells intact. Early clinical outcomes of GD2-CAR T-cell therapy for H3K27M-altered DMG demonstrate short-lived neurological and radiological improvement. Here, I aim to assess which molecules, co-expressed with the CAR, can potentiate CAR T-cell therapy, by improving trafficking, tumour penetration, and durability of therapeutic response.

METHOD: A co-expressing candidate molecule library was generated, including chemokine receptors (CCRs) to improve tumour homing towards tumour-secreted chemokines, adhesion molecules to increase extravasation across the blood–brain-barrier, and molecules to degrade upregulated tumour extracellular matrix components to improve tumour penetration. Co-expressing CAR constructs were cloned, labelled with unique DNA barcodes, and validated for co-expression with flow cytometry, and function when transduced into murine splenocytes. CAR T-cells co-expressing different molecules were administered simultaneously to tumour-bearing mice to in vivo select those CAR constructs which enhance ability to traffic to and penetrate high-grade gliomas. Both orthotopic syngeneic murine models of EGFRvIII-expressing GL261 (representing glioblastoma) and GD2-expressing H3K27M-altered DMG are being used.

RESULTS: Co-expression of enhancing module components alongside the CAR and retained function of the CAR has been confirmed. Pooled CAR T-cells co-expressing different CCRs have been administered to GL261-EGFRvIII tumour-bearing mice. Tumour, normal brain and non-CNS tissues were harvested and DNA extracted. Next Generation Sequencing is being used to determine CAR T-cells co-expressing which CCR (utilizing DNA barcodes) preferentially trafficked to the gliomas. Results from this and further experiments testing the full breadth of co-expressed molecules will be presented.

CONCLUSIONS: The multi-modular design of CAR constructs, allowing co-expression of potentiating molecules, has enormous scope for tailored optimisation of CAR T-cell therapy for DMG and other tumours.

Keywords: Paediatric high-grade glioma, Diffuse midline glioma (DMG), H3K27M-alteration, CAR T-cell therapy, T-cell trafficking

PF-005

Neuro-Oncology

Early Surgical Intervention Improves Central Nervous System Tumor Outcomes in Children with Li-Fraumeni Syndrome: Children’s National Hospital Experience and Literature Review

Nirali Patel¹, Kathleen Felton², Surajit Bhattacharya³, Maria Isabel Almira Suarez⁴, Joyce Turner⁵, Robert Keating¹, Chima Oluigbo¹, Lindsay Kilburn⁶, Roger Packer⁷, Miriam Bornhorst⁶, John S. Myseros¹

¹Department of Neurosurgery, Children's National Hospital, Washington, DC, USA

²Department of Pediatric Hematology/Oncology, University of Saskatchewan College of Medicine, Saskatchewan, Canada

³Center for Genetics Medicine Research, Children's National Hospital, Washington, DC, USA

⁴Department of Pathology, Children's National Hospital, Washington, DC, USA

⁵Department of Genetics and Metabolism, Children's National Hospital, Washington, DC, USA

⁶Department of Hematology/Oncology, Children's National Hospital, Washington, DC, USA

⁷Department of Neuroscience, Children's National Hospital, Washington, DC, USA

BACKGROUND AND AIM: Li-Fraumeni syndrome (LFS) is a cancer predisposition syndrome caused by germline mutations in the TP53 gene. CNS tumors are the fourth most common tumor type in LFS and recent screening guidelines, the Toronto Protocol, have proven that early tumor detection is associated with improved long-term survival7,8. Given the paucity of data in the literature, we highlight our experience with surgical resection of brain lesions, especially low-grade gliomas, identified on surveillance imaging in asymptomatic patients.

METHOD: Our cohort is comprised of children seen in the Pediatric Cancer Genetics Program ast Children’s National Hospital (CNH) from August 2012 to August 2021. We also include a literature search related to surveillance and CNS tumors in LFS patients.

RESULTS: Between August 2012 and August 2021, 10 children with germline TP53 mutations and CNS tumors were assessed at CNMC: four were known carriers of the TP53 mutation and found to have CNS lesions on surveillance imaging, while six were patients with symptomatic CNS lesions who were either known or subsequently found to have germline TP53 mutations. When added to the patients found in our literature review, we had a total of 56 CNS lesions: 24 low-grade and 26 high-grade lesions. The majority of the low-grade CNS lesions (22/24, 92%) were found on surveillance protocols in asymptomatic patients, while most of the high-grade CNS lesions (22/26, 85%) presented with symptoms in patients not undergoing routine surveillance or as the initial diagnosis of LFS. We noted a significant survival advantage in pediatric patients with a low-grade lesions, with an overall survival of 100% at 50 months.

CONCLUSIONS: Data presented in this study supports surveillance protocols in Li Fraumeni syndrome. In our experience, early surgical resection of low-grade lesions identified on surveillance imaging in asymptomatic patients leads to a significant survival advantage.

Keywords: Li Fraumeni Syndrome, brain tumor, Screening

PF-006

Neuroendoscopy

Endoscopic endonasal transsphenoidal surgery in children: widening the spectrum of oncological indications in the pediatric age group

Vincenzo Mastropasqua¹, Mario Rigante², Luca Massimi¹, Paolo Frassanito¹, Federico Bianchi¹, Gianpiero Tamburrini¹

¹Pediatric Neurosurgery, A. Gemelli Hospital, Rome, Italy

²ENT Surgery, A. Gemelli Hospital, Rome, Italy

BACKGROUND AND AIM: Endoscopic endonasal transsphenoidal surgery (EETS) is increasingly used in children to treat skull base lesions. The aim of this study is to present our institutional experience.

METHOD: Sixty-eight children (mean age: 11.4 years) were operated on with the EETS in our institution from 2008 to date. All the procedures were performed by a team including neurosurgeons and ENT surgeons. Hormonal tests were conducted before and after surgery. Perioperative ophthalmic examinations were carried out in patients with visual impairment. Multidisciplinary follow-up was conducted in all patients variably according to pathology.

RESULTS: Overall 86 procedures were performed, including tumor residuals/recurrences after a previous craniotomic approach (6), biopsies (1). Gross total tumor resection was achieved in 45 (54.2%) cases, while a subtotal and a partial resection were performed in 17 (20.5%) and 21 (25.3%) cases, respectively. Craniopharyngioma was the most common histotype (25), followed by pituitary adenoma (22), pilocytic astrocytoma (7), Rathke cleft cyst (6), chordoma (5), chondrosarcoma (4), germ cell tumor (3), angiofibroma (2). No surgical mortality or neurological morbidity or late nasal complications were observed. Postoperative CSF leak occurred in 6 patients (7%), 3 of which required a sellar floor duroplasty. Out of 38 children with tumor residuals, 18 (47.4%) had tumor progression that needed a second surgery, performed in 10 cases through EETS and in 8 cases through a craniotomic approach. Ten out of 45 children (22.2%) who underwent gross total resection had tumor recurrence, that required a second intervention (EETS in 7, craniotomic approach in 1 cases).

CONCLUSIONS: EETS has an increasing number of indications in children. Thanks to its safety and efficacy it has subsided the craniotomic approach as first surgical route in many skull base oncological diseases at diagnosis, as well as the main alternative in children with residual or recurrent anterior skull base lesions, initially operated through a craniotomy.

Keywords: Neuroendoscopy, Neuro-oncology

PF-007

Neuro-Oncology

Transcriptome Characterization of Pediatric Adamantinomatous Craniopharyngioma at the Cellular Level

Eric W. Prince¹, John Apps⁴, Oscar Chatain², Susan Staulcup¹, Carsten Georg², Juan Pedro Martinez Barbera³, Todd C. Hankinson¹

¹Children's Hospital Colorado and University of Colorado School of Medicine, Aurora, USA

²University of Colorado School of Medicine, Aurora, USA

³University College London Great Ormond Street Institute of Child Health, London, UK

⁴University of Birmingham, Birmingham, UK

BACKGROUND AND AIM: Adamantinomatous Craniopharyngioma (ACP) is a neurologically devastating brain tumor that affects children and adults. It is histologically heterogeneous with epithelial populations that are characterized by the nuclear accumulation of mutated β-catenin and activated Wnt signaling. Current models suggest that ACP growth is driven through paracine mechanisms characterized by the senescence-associated secretory phenotype (SASP). However, detailed pathogenic mechanisms remain unknown. Improved definition of the various cellular phenotypes that compose ACP will inform and advance our understanding of this disease.

METHOD: Single cell RNA-sequencing (scRNA-seq) and multiplex ELISA were performed on pediatric ACP tissue and cyst fluid, respectively. Reference scRNA-seq data was obtained from PanglaoDB. Preprocessing and standard analyses were conducted using Seurat software. Cellular phenotypes were annotated using the Human Primary Cell atlas. Differential expression and functional enrichment analyses were utilized to identify Wnt-signaling activation and epithelial subpopulations. Paracrine signaling was inferred via CellChatDB. SASP Atlas was utilized to query marker gene lists. Pseudotemporal ordering was performed using the dynamo software package.

RESULTS: ACP tissue is heterogenous and contains multiple distinct immune signatures. ACP tissue contains 2 unique epithelial subpopulations, which demonstrate canonical Wnt-signaling and SASP, respectively. Pseudotemporal ordering suggests the initial oncogenic event to be of epithelial character, with subsequent aggressive behavior from a separate epithelial cell population.

CONCLUSIONS: Based on gene expression, cell populations that correspond to the histologically identifiable epithelial whorls and palisading epithelium can be identified. These subpopulations display unique functional signatures. Simultaneous and synergistic therapeutic targeting of these separate epithelial populations may lead to improved patient care.

Keywords: Craniopharyngioma, Single cell RNA Sequencing, Pediatric craniopharyngioma, Deep sequencing, Gene expression

PF-008

Neuro-Oncology

Phase 0 and feasibility single-institution clinical trial of intravenous tocilizumab for adamantinomatous craniopharyngioma

Todd C. Hankinson¹, Lindsey Hoffman⁴, Ashley Mettetal², Molly Hemenway², Nathan Dahl¹, Shelby Winzent Oonk², Eric Prince³, Trinka Vijmasi³, Jennifer A. Mcwilliams³, Kimberly Jordan³, David Mirsky¹, Kathleen Dorris¹

¹Children's Hospital Colorado and University of Colorado School of Medicine, Aurora, USA

²Children's Hospital Colorado, Aurora, USA

³University of Colorado School of Medicine, Aurora, USA

⁴Phoenix Children's Hospital, Phoenix, USA

BACKGROUND AND AIM: Adamantinomatous craniopharyngioma (ACP) is a devastating skull-base tumor believed to derive from epithelial remnants of the primordial craniopharyngeal duct (Rathke’s pouch), which gives rise to the anterior pituitary gland. ACP lacks medical antitumor therapies. Current standard therapy with surgery and radiation is associated with poor quality of life. Clinical and preclinical data indicate that IL-6 blockade may contribute to ACP tumor control.

METHOD: Children aged 2–21 years with newly diagnosed or previously treated ACP with measurable disease are eligible for the Phase 0/feasibility single-institution clinical trial (NCT03970226) of intravenous (IV) tocilizumab at Children’s Hospital Colorado. The phase 0 stratum involves IV tocilizumab prior to a standard-of-care surgical resection. The feasibility portion of the trial involves IV tocilizumab every two weeks for up to 13 28-day cycles. Tocilizumab is administered at the established weight-based pediatric dosage of 8 mg/kg for patients who weigh ≥ 30 kg or 12 mg/kg for patients who weigh < 30 kg.

RESULTS: To date, three patients have been enrolled on the Phase 0 component of the trial. These patients demonstrated clinically relevant levels of tocilizumab (≥ 4 µg/mL) in serum, cyst fluid, and/or tumor tissue, compared to undetectable levels in control samples. Two patients (1 male and 1 female; median age 10.5 years) have enrolled on the feasibility stratum; one patient had best response of minor response but met definition of progressive disease at cycle 11. One patient with extensive disease required dose reduction for myelosuppression.

CONCLUSIONS: Systemic delivery of tocilizumab at the established pediatric dosage is promising for treatment of ACP based on preclinical work and its demonstrated penetration into cystic and solid portions of ACP tumors. The therapy to date has been well tolerated overall. Further study is planned through a CONNECT consortium international Phase II trial.

Keywords: Craniopharyngioma, Tocilizumab, Clinical tria, Pediatric craniopharyngioma, Adamantinomatous craniopharyngioma

PF-009

Neuro-Oncology

Cerebellar mutism syndrome (CMS) following posterior fossa surgery in children below 18 years, what we have learnt over the last 10 years

Stephanie Sally Schmidt¹, Edina Kovacs¹, Felix Sahm², Till Milde³, Andreas Unterberg¹, Ahmed El Damaty¹

¹Department of Neurosurgery, Heidelberg University Hospital, Heidelberg, Germany

²Department of Neuropathology, Heidelberg University Hospital, Heidelberg, Germany

³Department of Paediatric Neurooncology, Heidelberg University Hospital, Heidelberg, Germany

BACKGROUND AND AIM: The aim is to evaluate our institutional experience with tumor resection in the posterior fossa in children and the incidence of CMS postoperatively, and to analyze association with multiple risk factors, such as tumor entity, size and location, surgical approach, usage of ultrasonic cavitation device and hydrocephalus.

METHOD: All patients below 18 years, who received a tumor resection in the posterior fossa between January 2010 and March 2021 were included for retrospective analysis. Various data points, including demographic, tumor-associated, clinical, radiological, surgery-associated, complications and follow-up data were collected and statistically evaluated for association with CMS.

RESULTS: 60 patients were included with a median age of 8 years (range 0–18). Integrated diagnosis showed 48% pilocytic astrocytoma, 32% medulloblastoma, 10% anaplastic ependymoma and 13% other tumor entities. Complete resection was achieved in 68%, 23% underwent subtotal resection and 7% underwent partial resection.

43% were operated using a telovelar approach, 8% using a transvermian approach and 48% using other approaches. 16% developed CMS postoperatively, following telovelar approach in 15% and 60% following a transvermian approach. Medulloblastoma patients and midline tumors showed a higher incidence of CMS, though not significant. Tumor size and infiltration of the brainstem did not differ significantly in our cohort.

Presence of acute hydrocephalus was associated with a significantly higher risk for developing CMS (p 0.01) as well as need for a ventriculoperitoneal shunt (p 0.04). Usage of an ultrasonic cavitation device was not associated with CMS. All patients with CMS showed marked improvement during follow up but with residual deficits.

CONCLUSIONS: Our CMS rates compare to those described in literature. CMS was not only associated with a transvermian approach, but also occurs using a telovelar approach, but to a lesser extent. Presence of acute hydrocephalus prior to tumor surgery is associated with higher incidence of CMS.

Keywords: Cerebellar mutism syndrome, posterior fossa syndrome

PF-010

Neuro-Oncology

Clinicohistoradiological And Surgical Outcome In Diffuse Midline Glioma

Arvind Kumar Suman

Nizam's institute of medical sciences, Hyderabad, India, 500,082

BACKGROUND AND AIM: Diffuse midline glioma’s (DMGs) include central nervous system tumors, containing a characteristic H3K27M mutation and found in the midline location of brain and spinal cord.

To determine the clinical, pathological, radiological & surgical outcome, disease severity of DMG patients who have undergone surgery and to find better therapeutic options.

METHOD: 29 diffuse midline glioma patients were recruited. Clinical, pathological, radiological & surgical outcomes were noted and correlated with survival.

RESULTS: KI67% was compared between < 18 and > 18yrs age groups, it was found that KI67% was higher in < 18yrs age group (24.92 ± 13.66, p = 0.08) compared to > 18yrs age group (16.47 ± 10.19) and found to have trend towards significance and it was also found that KI67% was significantly low in the population with > 6 months disease duration (12.2 ± 4.712mnths, p = 0.012) compared to < 6 months disease duration population (21.58 ± 12.79mnths).

Survival duration was significantly high in patients with age > 18 years (232.06 ± 265.75 days; p = 0.02) compared to < 18 years age (50.16 ± 47.79 days). The patients who took radiation therapy found to show significantly higher survival rate (341.25 ± 318.05 days, p = 0.05) compared to those who were not taken (69.89 ± 71.5). Patients who required shunt placement found to have significantly lower survival duration (43.6 ± 30.35 days, p = 0.02) compared to patients who did not require shunt placement (215.56 ± 263.55 days). Patients with improved post op outcome (10.8 ± 4.08, p = 0.002) were having significantly low level of KI67% compared to not improved cases (21.87 ± 12.58) and KI67% was negatively correlated with survival duration (r = -0.40; p = 0.0358).

CONCLUSIONS: Our study concludes that KI67% and H3K27M serves as the markers and prognosticates the survival duration in pediatric population and also pediatric population has more severe disease compared to Adult population.

Keywords: Diffuse midline glioma, KI67%

PF-011

Neuro-Oncology

Is external ventricular drainage (EVD) necessary? The role of temporary CSF diversion for management of posterior fossa tumor resection: a 17-year experience at a single institution

Hasan Raza Syed¹, Nirali Patel², Sukhjeevan Nijhar³, Kelsey Chesney², Katherine Hoffmann¹, Daniel Donoho¹, Chima Oluigbo¹, Robert Keating¹, John Myseros¹

¹Department of Neurosurgery, Children’s National Hospital, Washington DC

²Department of Neurosurgery, MedStar Georgetown University Hospital, Washington DC

³Georgetown University School of Medicine, Washington DC

BACKGROUND AND AIM: Children with posterior fossa tumors commonly present with obstructive hydrocephalus (80% in literature). Conventional doctrine has dictated external ventricular drainage (EVD) pre- or perioperatively for various purposes. Here, we highlight our experience with a less invasive approach that avoids EVD in the neurologically stable patient and decreases associated complications and hospital length of stay.

METHOD: We retrospectively collected data on all pediatric patients with posterior fossa tumors treated at Children’s National Hospital (CNH) from 2005–2021. Diagnostic and treatment variables included hydrocephalus at presentation, placement of external ventricular drain pre- or perioperatively, and final pathology. Outcome variables included complications, placement of permanent shunt, and length of stay (LOS).

RESULTS: 110 of 137 patients with posterior fossa tumors (80.3%) had hydrocephalus. All patients underwent resection that was volumetrically significant enough to reestablish the CSF pathways. Of the 65 patients (59.1%) that had pre- or peri-operative EVD placement, 10.8% experienced a complication, including infection, hemorrhage, or CSF leak, with 40% requiring permanent CSF diversion. Of those patients with no EVD (n = 45, 40.9%), 4.4% had either a CSF leak or pseudomeningocele, and only 15.6% required treatment for unresolved hydrocephalus (p < 0.01). None of these patients required pre-, peri-, or post-operative emergent procedures for untreated hydrocephalus. Length of stay was also significantly less compared to those patients with EVD (mean LOS 4.2 vs 9.1 days, p < 0.01).

CONCLUSIONS: Although relative risks of EVD are low in general, our experience shows that avoiding placement of an EVD decreases these risks even further, including the need for permanent CSF diversion post-resection. As such, depending on the surgeon’s comfort and the presenting symptoms, even in children with significant radiographic hydrocephalus, EVD may not be necessary, and adequate resection offers excellent chances for resolution of the hydrocephalus with decreased complications and a significant reduction in permanent CSF diversion and LOS.

Keywords: Posterior fossa tumor, Brain tumor, Hydrocephalus, Shunt, External ventricular drain, Complications

PF-012

Neuro-Oncology

Thalamic Tumors in Children: Surgical Outcome, Genetic and Clinical Features in a Retrospective Series of 110 Patients

Lelio Guida¹, Kevin Beccaria¹, Thomas Blauwblomme¹, Volodia Dangouloff Ros², Nathalie Boddaert², Stephanie Puget¹

¹Department of Neurosurgery, Hôpital Necker Enfants Malades, Université de Paris Cité, Paris, France

²Department of Neuroradiology, Hôpital Necker Enfants Malades, Université de Paris Cité, Paris, France

BACKGROUND AND AIM: The treatment of tumors arising from the thalamus has changed over the decades, surgery gaining an important role in the management of these patients, especially in the case of low-grade tumors. In case of high-grade thalamic lesions, the relevance of surgery remains controversial, notably in the subgroup of patients with histone H3F3A K27M mutated tumors. We aimed to find radiological features that may predict high grade and H3F3A K27M mutated lesions, to define the outcome of histone-mutated patients and eventually to clarify the role of surgery in these patients.

METHOD: This is a monocentric, retrospective study. Clinical, neuroradiological and histological features were analyzed, as well as surgical strategy and clinical outcome. Univariate and multivariate analysis was performed for continuous and categoric variables. Survival analysis was made with according to the Kaplan–Meier method and Cox model.

RESULTS: 110 children were enrolled into the studies (50 unilateral thalamic tumors, 43 thalamopeduncolar, 17 bithalamic). In multivariate analysis, intra-tumoral cysts were associated with a decreased likelihood of high grade gliomas, while hyperperfusion and diffusion restriction were more likely to be found in aggressive lesions (Fig. 1). Seventy-nine percent of patients underwent debulking surgery of whom 55% had subtotal or gross-total resection. In survival analysis, bithalamic tumors, K27M histone mutation and EGFR mutation were associated to the poorest prognosis (Fig. 2). A significative difference of mean survival time was found (13,7 ± 5,9 vs 24,1 ± 5,3) among histone mutated patients according to extent of resection.

CONCLUSIONS: Molecular profile of thalamic tumors is essential in defining patient prognosis and management. Surgery has a prominent role in both low-grade and high-grade tumors in improving the outcome of patients with thalamic tumors.

Keywords: Thalamic tumors, Thalamopeduncular tumors, Bithalamic tumors, H3F3A K27M mutation

PF-013

Neuro-Oncology

HDAC inhibitor, PI3K mTOR and combined HDAC/PI3K inhibitors in treatment of mutant P53 Medulloblastoma

Tolga Sursal¹, Jose Dominguez¹, Raphael Salles Scortegagna De Medeiros², Sidnei Epelman², Michael E Tobias¹, Avinash L Mohan¹, Nelci Zanon³, Chirag D Gandhi¹, Meena Jhanwar-Uniyal¹

¹Department of Neurosurgery, New York Medical College/Westchester Medical Center, Valhalla, New York, USA

²Department of Pediatric Oncology, Hospital Santa Marcelina, Sao Paulo, Brazil

³Department of Pediatric Neurosurgery, Hospital Santa Marcelina, Sao Paulo, Brazil

BACKGROUND AND AIM: Medulloblastoma (MB) is the most common primary pediatric malignant brain tumor. Molecular analysis classifies MB into 3 groups, classic (WNT), sonic hedgehog (Shh), and non-WNT/non-SHH. Abnormal p53 signaling is associated with disease progression and confers poor prognosis. This study examined the correlation of p53 mutation and status of iSO17q status with disease progression and metastatic potential and studied the effect of HDAC inhibitor, PI3K, mTOR and combined HDAC/PI3K inhibitors in aim of finding a novel therapeutic agent for p53-mutant MBs.

METHOD: MB tumors (n = 53) were assessed for the of GLI-1, GAB-1, NPR, KV1, YAP expression and mutant p53 via immunohistochemistry and correlated to patient outcomes. Fluorescence in-situ hybridization (FISH) was used to determine the Isochromosome 17q(iso(17q)). Effect of small molecule inhibitors, targeting HDAC (LBH-589), PI3K (Buparlisib), mTOR inhibitor (Torin1, Torin2) and combined HDAC/PI3K inhibitor (CUDC-907) was assessed via functional assays (cell proliferation, migration, cell cycle, and drug resistance).

RESULTS: High expression of GAB-1 and YAP in SHH group while KV1 expression was present in all subtypes. Mutant p53 was present in various subset of MB with no apparent correlation with metastasis or disease progression, however, one atient displaying iso17q exhibited metastatic disease. LBH-589, Buparlisib, Torin1, Torin2 and CUDC-907, caused a dose and time dependent inhibition of MB cell proliferation and migration. MB cells were resistant to PI3K inhibitor Buparlisib demonstrated by drug-resistance studies. These inhibitors function by targeting components of mTOR pathway.

CONCLUSIONS: GLI-1, GAB-1, NPR, KV1, YAP expression, and mutant p53 are essential criteria for defining metastatic potential of the MB sub-groups. While a significant number of MB samples displayed mutant p53, their association with the disease remains unclear however the presence of iso17q may define metastatic potential in MB. Furthermore, small molecule inhibitors of PI3K, Torin1, Torin2 and HDAC provide a novel option for treatment of MB.

Keywords: Medulloblastoma p53 sonic hedgehog (SHH) HDAC inhibitor PI3K mTOR

PF-014

Vascular

Delayed recurrence of pediatric arteriovenous malformations after radiologically confirmed obliteration

Soliman Oushy, Hannah E Gilder, Cody L Nesvick, Giuseppe Lanzino, Bruce E Pollock, David J Daniels, Edward S Ahn

Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota

BACKGROUND AND AIM: Arteriovenous malformations (AVMs) are a major cause of intracerebral hemorrhage in children, resulting in significant morbidity and mortality. Moreover, the rate of AVM recurrence in children is significantly higher than in adults. The aim of this study was to define the risk of delayed pediatric AVM (pAVM) recurrence following confirmed radiological obliteration. Further understanding of this risk could inform the role of long-term radiological surveillance.

METHOD: The authors conducted a retrospective review of ruptured and unruptured pAVM cases treated at a single tertiary care referral center between 1994 and 2019. Demographics, clinical characteristics, treatment modalities, and AVM recurrence were analyzed.

RESULTS: 102 children with intracranial AVMs, including 52 (51%) ruptured cases, were identified. The mean patient age at presentation was 11.2 ± 4.4 years, and 51 (50%) patients were female. Mean nidus size was 2.66 ± 1.44 cm. The most common Spetzler-Martin grades were III (32%) and II (31%). Stereotactic radiosurgery was performed in 69.6% of patients. AVM obliteration was radiologically confirmed in 68 (72.3%) of 94 patients [AQ? See query in Results, Radiological AVM Obliteration.], on angiography in 50 (73.5%) patients and on magnetic resonance imaging in 18 (26.5%). AVM recurrence was identified in 1 (2.3%) of 43 patients with long-term surveillance imaging over a mean follow-up of 54.7 ± 38.9 months (range 2–153 months). This recurrence was identified in a boy who had presented with a ruptured AVM and had been surgically treated at 5 years of age. The AVM recurred 54 months after confirmed obliteration on surveillance digital subtraction angiography. Two other cases of presumed AVM recurrence following resection in young children were excluded from recurrence analysis because of incomplete sets of imaging available for review.

CONCLUSIONS: AVM recurrence is a rare phenomenon, though it occurs more frequently in children. Regular long-term follow-up with dedicated angiography is recommended following resection.

Keywords: Pediatric, AVM, Arteriovenous malformations, Recurrence, Obliteration, Vascular disorders

PF-015

Moya-Moya disease

Neurosurgical management of Proton Beam Therapy-induced Moyamoya Syndrome

Catherine Zhang¹, William Muirhead¹, Adikarige Silva¹, Claire Toolis¹, Fergus Robertson³, Adam Rennie³, Sanjay Bhate², Dominic Thompson¹, Vijeya Ganesan², Greg James¹

¹Department of Neurosurgery, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom

²Department of Paediatric Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom

³Department of Neuroradiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom

BACKGROUND AND AIM: Proton beam therapy(PBT) is being increasingly used to treat paediatric brain tumours. Moyamoya syndrome (MMS) is a well-recognised complication following photon radiotherapy, however its association with PBT is less well documented. We describe our experience with the neurosurgical management of post-PBT MMS in a single institution in the United Kingdom.

METHOD: Retrospective review of patients diagnosed with post-PBT MMS within the past 20 years at Great Ormand Street Hospital, London. Patient details including demographics, oncological history and treatment, MMS diagnosis and treatment were recorded. Clinical outcome was classified as “Good” if mRS 2 or less, or attending mainstream school without additional assistance. “Poor” grade was deemed to be mRS 3 or more, or requiring assistance at school.

RESULTS: 10 patients were identified. Tumour types were 6craniopharyngiomas, 2sarcomas, 1optic pathway glioma, and 1ependymoma. Median age at PBT was 4.4 years (IQR 1.9—6 years), and MMS diagnosis was 7.8 years (IQR 5.7 – 9.3 years) (Fig. 1). Median time between PBT and diagnosis of MMS was 20 months (IQR 14.5 – 41.0 months). 6 patients had poor functional outcome at the end of their initial oncological treatment, and prior to the diagnosis of MMS. All patients had pituitary dysfunction, 8 had visual impairment, and 4 had behavioural issues prior to MMS diagnosis.

3 patients had an ischaemic event during a peri-operative period: 2 following tumour surgery, and 1 following MMS surgical revascularisation(SR). 1 patient had an ischaemic event following general anaesthetic for oncological surveillance MRI scan.

3 patients’ MMS were managed medically, and 7 underwent SR. Number of ischaemic events were reduced following SR (Fig. 2).

CONCLUSIONS: MMS can occur following PBT, with a clinical profile which can place these patients at high risk of ischaemic events. In selected patients, SR can prevent further neurological insults to a group of patients who frequently have neurodisabilities consequent upon their primary brain tumour.

Keywords: Moya moya syndrome, Proton beam therapy, Surgical revascularisation, Post-radiation moya moya syndrome

PF-016

Moya-Moya disease

Outcome prediction of pediatric moyamoya disease using midterm cerebral blood flow measured between staged anastomoses

Sadahiro Nomura, Fumiaki Oka, Natsumi Fujii, Hideyuki Ishihara

Department of Neurosurgery, Yamaguchi University, Ube, Japan

BACKGROUND AND AIM: Cognitive outcomes of pediatric moyamoya disease are variable and difficult to predict on the basis of initial neurological signs and examinations. To determine the best early time point for outcome prediction, we retrospectively analyzed the correlation between cognitive outcomes and the cerebrovascular reserve capacity (CRC) measured before, between, and after staged bilateral anastomoses. ± 

METHOD: Twenty-two patients aged 4–15 years were included in this study. CRC was measured before the first hemispheric surgery (preoperative CRC), 1 year after the first surgery (midterm CRC), and 1 year after the surgery on the other side (final CRC). The cognitive outcome was the Pediatric Cerebral Performance Category Scale (PCPCS) grade more than 2 years after the final surgery.

RESULTS: The 17 patients with favorable outcomes (PCPCS grades 1 or 2) showed a preoperative CRC of 4.9% ± 11.2%, which was not better than that of the five patients with unfavorable outcomes (grade 3; 0.3% ± 8.5%, p = 0.5). The 17 patients with favorable outcomes showed a midterm CRC of 23.8% ± 15.3%, which was significantly better than that of the five patients with unfavorable outcomes (–2.5% ± 12.1%, p = 0.004). The difference was much more significant for the final CRC, which was 24.8% ± 13.1% in the patients with favorable outcomes and –11.3% ± 6.7% in those with unfavorable outcomes (p = 0.00004).

CONCLUSIONS: Cognitive outcomes were first clearly discriminated by the CRC after the first-side unilateral anastomosis, which is the optimal early timing for prediction of individual prognosis.

Keywords: Cerebral ischemia, Cerebrovascular reserve capacity, Prognosis, Single photon emission computed tomography

PF-017

Vascular

Multi-modality Treatment Approach for Paediatric AVMs with Quality of Life Outcome Measures

John C. Duddy¹, Natasha Aziz², Danial Saeed³, Dawn Hennigan¹, Anil Israni⁴, Mani Puthuran³, Arun Chandran³, Conor Mallucci¹

¹Department of Neurosurgery, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

²School of Medicine, University of Liverpool, UK

³Department of Neuroradiology, The Walton Centre NHS Foundation Trust, Liverpool, UK

⁴Department of Neurology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

BACKGROUND AND AIM: Intracranial AVM rupture is the leading cause of spontaneous childhood intracerebral haemorrhage (ICH). AVM rupture is associated with a 30–50% risk of neurological deficit and 5–10% risk to life. The aim of this study is to evaluate management strategies of paediatric intracranial AVMs at our institution and to measure long-term quality-of-life outcomes.

METHOD: This retrospective case-series included all patients aged 0-18 years diagnosed with intracranial AVM from July 2007-March 2021. Multiple AVMs in one patient were treated separately. We collected data on: presenting symptoms; Spetzler-Martin Grade(SMG); time to treatment; type of treatment; post-operative complications; post-treatment obliteration rates; and quality of life outcomes measured using the PedsQL score.

RESULTS: We identified 57 patients between June 2007-March 2021. 8 patients were excluded due to insufficient data. 49 patients with 50 AVMs were included. 40(80%) AVMs presented with acute ICH. Of the remaining 10(20%), 4(8%) were incidental scan findings. The mean time to definitive treatment was 144 days.

25(50%) patients were surgically treated. Complete obliteration was achieved in 22(88%). There was no AVM recurrence and 1 rebleed reported on follow-up (mean 2.9 years). 15 children underwent endovascular embolization as either standalone treatment or multimodal AVM treatment strategy. Complete obliteration was achieved in 67%. 15 children underwent SRS as either a standalone treatment or multimodal AVM treatment strategy. Complete obliteration was achieved in 8(42%).

20(41%) patients completed the PedsQL outcome measurement model. PedsQL measures health-related quality of life in children and adolescents on a scale from 0–100. The average total score was 63.08 with average physical and pyschosocial scores of 64.5 and 62.375, respectively (Median scores:77.5; 66.25; 64.165).

CONCLUSIONS: A multi-modality treatment approach achieves a high rate of complete obliteration of paediatric AVMs. AVM recurrence and rebleed rates are low. Quality of life for children is significantly impacted by AVM diagnosis.

Keywords: AVM, Haemorrhage, Surgery, SRS, Endovascular, Quality-of-life

PF-018

Dysraphism

Motor-sensory disconnect in fetal myelomeningocele closure patients: intraoperative neurophysiological monitoring in tethered cord release

Tracy M. Flanders¹, Alier J. Franco², Kristen L Lincul³, Samuel Pierce³, Katie M. Schmidt⁴, Kaitlin R. Lehmann⁵, Ena A. Agbodza⁵, Deborah M. Zarnow⁶, Edward R. Oliver⁶, Beverly G. Coleman⁶, Jesse A. Taylor⁷, Julie S. Molenhauer⁸, N. Scott Adzick⁸, Gregory G. Heuer¹

¹Division of Neurosurgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA

²Division of Pediatric Intraoperative Neuromonitoring, SpecialtyCare, Nashville, TN, USA

³Department of Physical Therapy, Children's Hospital of Philadelphia, Philadelphia, PA, USA

⁴The Center for Fetal Diagnosis and Treatment, Children's Hospital of Philadelphia, Philadelphia, PA, USA

⁵Center for Data Driven Discovery in Biomedicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA

⁶Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA

⁷Division of Plastic and Reconstructive Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA

⁸Division of Pediatric General, Thoracic, and Fetal Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA

BACKGROUND AND AIM: Patients after MMC closure can develop symptomatic spinal cord tethering, i.e. tethered cord syndrome (TCS), in as many as 30% of patients. Our goal was to better understand the clinical course and impact of tethered cord release surgery on patients who have previously undergone open spinal dysraphism closure in utero.

METHOD: This is a single-center retrospective observational study on patients undergoing tethered cord release after having previously had open fetal myelomeningocele (MMC) closure. All patients underwent tethered cord release surgery with a single neurosurgeon. A detailed analysis of the patients’ preoperative presentation, intraoperative neuromonitoring (IONM) data, and postoperative course was performed with a particular emphasis on motor and sensory function during these periods.

RESULTS: From 2009 to 2021, 51 patients who had previously undergone fetal MMC closure had tethered cord release surgery performed. On both preoperative and postoperative manual motor testing, patients were found to have on average 2 levels better than would be expected from the determined anatomic level from fetal imaging. The electrophysiologic functional level was found on average to be 2.5 levels better than the anatomical fetal level. Postoperative motor levels when tested on average at 4 months were largely unchanged when compared to preoperative levels. Unlike the motor signals, 46 (90%) of patients had unreliable or undetectable lower extremity somatosensory evoked potentials (SSEPs).

CONCLUSIONS: Tethered cord surgery can be safely performed in patients after open fetal MMC closure without clinical decline in manual motor testing. Patients often have functional nerve roots below the anatomic level. Sensory function appears to be more severely affected in patients leading to a consistent motor-sensory imbalance. This imbalance may affect strategies for physical therapy and rehabilitation.

Keywords: Fetal, Intraoperative neuromonitoring (IONM), Myelomeningocele, Tethered cord

PF-019

Dysraphism

Transitional Care for Spina Bifida: A Systematic Review

Nathan A Shlobin, Klaudia Dziugan, Joshua Simon, Sandi Lam, Michael Decuypere, Robin Bowman

Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Division of Pediatric Neurosurgery, Lurie Children’s Hospital, Chicago, IL, USA

BACKGROUND AND AIM: Transition from pediatric to adult care presents challenges for people with spina bifida (SB) and families. However, there is a paucity of synthesis regarding transitional care for this patient population. We performed a systematic review to delineate the current state of transitional care; identify barriers, facilitators, and needs for transitional care; and characterize best practices for transitional care for people with SB

METHOD: PubMed, Embase, and Scopus were searched. After deduplication, articles were screened by title and abstract. Remaining articles were screened by full text. Bibliographic data were extracted.

RESULTS: Of 1,745 resultant articles, 32 were included. Transition of care was most often discussed within the context of urology, with no articles focusing on neurosurgical aspects. People with SB experience multiple transitions of care that may occur at different timeframes. Approximately 53–58% of transition-age people with SB are unemployed, 16–26% live independently, and 71% do not have a partner. Contributing factors include type of SB, presence of hydrocephalus, level of lesion, and activity limitations. Similarly, youth with SB who progress toward transition have higher cognitive functioning, interest in being independent, exposure to a independence-facilitating parenting style, and proficiency in negotiating primary care responsibilities with adult healthcare providers. Transition readiness, transition completion, and transition success represent key steps in the transition process. Physicians often do not discuss transitional care, while existing transitional care clinics often provide inadequate services. Effective transitional care models lead to regular home visits and appointments with SB specialists, allow easy access to medical care, and promote good quality of life.

CONCLUSIONS: Transitioning from child to adult care is an essential step for people with SB. Transitional care gaps exist, particularly on the level of providers. Adequate transitional care practices are necessary to address the needs of people with SB and families.

Keywords: Dysraphism, Spinal dysraphism, Spina bifida

PF-020

Other

Separation of conjoined spinal cords in 2 cases of rachipagus and pyopagus twins: Technical notes and the value of IONM

Llewellyn Padayachy

Department of Neurosurgery, University of Pretoria, Pretoria, South Africa

BACKGROUND AND AIM: Separation of conjoined twins presents a unique challenge, due to the anatomical and physiological complexity involved. Outcomes have improved, largely due to advances in imaging, virtual planning, surgical proficiency and monitoring techniques. The incidence of spinal cord attachment in pyopagus twins is 1: 100, 000, and rachipagus twins are even rarer. This work therefore represents valuable planning and technical surgical details acquired from a series of exceptionally rare cases of twin separation.

METHOD: The rachipagus twin involved an attachment of the head and spine of the parasitic twin at the T6-T8 level of the live twin, with a bony spur splitting the spinal cord. The spinal cord attachment for the pyopagus twins was at the level of L4/ L5, with no other visceral sharing. The surgical planning for both these cases were novel and innovative, including 3D printing of the models for bony and soft tissue anatomy, advanced MRI and 3D CT sequencing, as well multidisciplinary team involvement. Adjuncts to the surgery included, neuronavigation, intra-operative neurophysiological monitoring and imaging.

RESULTS: Separation of the rachipagus twin was done microsurgically. The parasitic twin remnant included an encephalocoele, with a bony spur splitting the spinal cord. This was circumferentially dissected under motor evoked potential monitoring. The pyopagus twin separation was done under more emergent conditions as one of the twins developed necrotising enterocolitis. Lower limb function in both cases were preserved and our rachipagus twin demonstrated further neurological improvement after pediatric neurorehabilitation.

CONCLUSIONS: The application of advanced surgical planning strategies, as well as appropriate intra-operative adjuncts can greatly assist in optimising surgical outcomes. This is well demonstrated in this series of incredibly rare and complex spinal cord separation in twins.

Keywords: Rachipagus, Pyopagus twins

PF-021

Dysraphism

Dysraphisms: towards a new European classification

Timothée De Saint Denis¹, Ferdinand Dhombres², Pauline Lallemant³, Catherine Garel⁴, Federico Di Rocco⁵, Jean Marie Jouannic²

¹Department of Neuro-Orthopedic Surgery, Trousseau Hospital, Paris, France

²Department of Fetal Medecine, Trousseau Hospital, Paris, France

³Department of Rehabilitation Medecine, Trousseau Hospital, Paris, France

⁴Departmendt of Radiology, Trousseau Hospital, Paris, France

⁵Department of pediatric neurosurgery, HCL, Lyon, France

BACKGROUND AND AIM: Spinal dysraphisms classifications are mainly anatomical and based on embryological assumptions. However, we also need a prognosis classification for prenatal counselling and a therapeutic classification for management and follow-up. In order to design such classifications, we intend to dissect dysraphisms in different features which all together can coincide with already known categories such as Myelomeningocele, MyeLDM, LDM or Conus Lipoma.

METHOD: We reviewed 47 dysraphism cases treated in our Rare Disease center with skin, bone or spinal cord features. Using a specific ontology-based model, we created a data bank that can aggregate all reviewed features into a whole malformation. Known association has been made under 7 commonly used terms for spinal dysraphisms. Validation of terms has been discussed during ERN experts committee before evaluation of reproducibility by a multidisciplinary medical panel.

RESULTS: 35 features have been used to describe the whole combinations that compose the variety of spinal dysraphisms. Each feature can be associated with a grade of prognosis and management, more than closed categories actually used. Overlap of the currently used categories of dysraphism can lead to confusion in diagnosis and treatment decisions.

CONCLUSIONS: Rethinking the way we describe dysraphism cases can help to homogenate and improve prenatal counselling and medico-surgical management. This new composition of classification is proposed to revise existing classification such as Orphanet Classifications of Rare diseases and Orphanet Ontology of Rare Diseases (ORDO). This could help both improve medical decision making and patients knowledge about their condition.

Keywords: Dysraphism, Classification, Rare Disease

PF-022

Antenatal diagnosis and treatment

Fetal myelomeningocele repair: is open hysterotomy still the standard approach?

Carlos Eduardo Barros Jucá¹, Francisco Edson De Lucena Feitosa⁴, Francisco Herlânio Costa Carvalho⁴, Antonio Aldo Melo Filho³, Tainã Brito Siebra De Oliveira⁵, Carolina Carmona Pinheiro Machado²

¹Department of Pediatric Neurosurgery, Albert Sabin Children’s Hospital, Fortaleza, Brazil

²Medical School, Universidade de Fortaleza, Fortaleza, Brazil

³Department of Pediatric Surgery, Albert Sabin Children’s Hospital, Fortaleza, Brazil

⁴Department of Obstetrics and Gynecology, Maternidade Escola Assis Chateaubriand, Fortaleza, Brazil

⁵Department of Women, Child and Youth Health, Universidade Federal do Ceará, Fortaleza, Brazil

BACKGROUND AND AIM: Since the onset of Management of Myelomeningocele Study (MOMs) in 2011, prenatal intervention for myelomeningocele repair is becoming the standard once its advantages regarding motor improvement and lower risk of hydrocephalus have been demonstrated. However, some alternative approaches have been developed, the fetoscopic one. The aim of this study is to evaluate if the open hysterotomy approach is still the standard technique.

METHOD: We analyzed 25 cases of prenatal myelomeningocele repair operated in a regional reference center in Brazil using the open hysterotomy technique with the externalized uterus. The first case was operated on May 2019 and the last one on April 2022. Comparisons between our outcomes and those documented in the literature for MOMs’ trial, other series and fetoscopic treatment were performed.

RESULTS: The average maternal age in our series was 31,7 years old. Medium gestational age was 26 weeks. There was fetal bradycardia in 4% of cases and there was only one perinatal death, due to rapidly progressive hydrocephalus after surgery. Birth after 37 weeks occurred in 16% of cases and the average gestational age at birth was 33,8 weeks. Until this moment, it was necessary to perform shunt placement in 12% of the born operated children. The need for shunting for hydrocephalus was substantially lower than MOMS and fetoscopy. We also had less cases of chorioamniotic separation. There was no dehiscence at the repair site. Fetoscopic treatment has a risk of 20% of surgical dehiscence of myelomeningocele according to literature.

CONCLUSIONS: Open hysterotomy technique for prenatal myelomeningocele repair has similar fetal outcomes than the fetoscopic approach but has fewer local complications and less cases of dehiscence and fistula. Once the defect closure is a major goal of the intervention, open hysterotomy remains preferable based on available data. However, the fetoscopic approach tends to evolve soon to improve and gain space.

Keywords: Myelomeningocele, Prenatal surgery, Fetoscopy, Pediatric neurosurgery, Pediatric surgery

PF-023

Dysraphism

Postoperative Tethered Cord After Open and Fetoscopic Spina Bifida Repair

Ibrahim Alatas¹, Seyhmus Kerem Ozel⁴, Bahattin Ozkul¹, Huseyin Canaz³, Revna Cetiner², Nafiye Sanlier², Teoman Karakurt², Mehmet Ozgur Yilmaz², Oguz Alp Cakir², Okan Turk², Doga Ugurlar²

¹Baskent University Hospital, Istanbul, Turkey

²Istanbul Training and Research Hospital, Istanbul, Turkey

³Medilife Hospital, Istanbul, Turkey

⁴Goztepe Training and Research Hospital, Istanbul, Turkey

BACKGROUND AND AIM: Spina bifida is the most common neural tube defect and its treatment options are evolving day by day. Fetal surgical repair of this defect and its clinical outcome are gaining interest and are increasingly seen as subjects of research even though early postnatal repair is routinely recommended for meningomyelocele.

The aim of this study was to evaluate the postoperative outcome of three cases of open and three fetoscopic repair of spina bifida in our spina bifida center since 2015.

METHOD: The data of cranial and vertebral MRI, urodynamics, neurological examination and ambulation scales were investigated in all six patients while evaluating the thickness of the granulation tissue at the surgical site from the perspective of tethered cord syndrome.

RESULTS: Findings of this study reveal that tethered cord detection in MRI was higher in patients after fetoscopic repair than open repair. Dermoid inclusion cysts have been accused in the development of tethered cord after fetal spina bifida repair. Our results point that high incidence of tethered cord after fetoscopic repair may be due to the foreign body reaction to the dura patch used in this procedure.

CONCLUSIONS: Fetal surgical repair of spina bifida is gaining popularity and different techniques may cause different outcomes in these patients. More common tethered cord after fetoscopic repair should be regarded as one of these issues.

Keywords: Spina Bifida, Meningomyelocele, Fetal Surgery, Tethered cord syndrome

PF-024

Spine

Cranio-cervical mobility assessment in dynamic magnetic resonance imaging in children

Flavie Grenier Chartrand, Maxime Taverne, Giovanna Paternoster, Raphaël Levy, Kévin Beccaria, Timothée De Saint Denis, Nathalie Boddaert, Thomas Blauwblomme, Roman H. Khonsari, Syril James, Sandro Benichi

Hôpital Universitaire Necker enfants malades, Assistance publique hôpitaux de Paris, Paris, France. Université Paris-Cité, Paris, France

BACKGROUND AND AIM: Dynamic MRI (dMRI) might be effective and safe to assess the stability of the cranio-cervical junction (CCJ) in children, but its interpretation is still an issue since no diagnostic criteria of instability is provided in the current literature. Our goal was to determine morphometric static and dynamic MRI criteria of mobility to distinguish stable and unstable patients.

METHOD: Monocentric retrospective analysis of all the cranio-cervical dMRI from 2017/01/01 to 2021/12/31. Patients underwent 2D sagittal T2 MRI with acquisitions in neutral position, flexion and hyperextension of the head. To assess CCJ mobility in dynamic conditions, delta (difference between extension and flexion) of seven morphometric parameters were measured in all positions: basion-dens interval (BDI), basion-axis interval (BAI), clivo-axial angle (CXA), C1-C2 cobb angle, PbC2 line (PbC2), Klaus index and C2-opisthion distance. We performed a hierarchical clustering on principal component analysis to define groups given their mobility similarities. Logistic regression was used to predict mobility in static neutral position.

RESULTS: 47 children were included (26 females, 21 males; mean age of 10 years): 17 patients with Chiari I, 10 complex craniosynostosis and 20 constitutional bone diseases. BDI delta (dBDI), CXA delta (dCXA) and PbC2 delta (dPbC2) were indicators of mobility between patients, and two groups were identified: Group 1 with “normal mobility” (n = 40) and Group 2 with “hypermobility” (n = 7). Cut-off with high predictability of mobility (area under curve of 1, 1, and 0,975 respectively) were established for dBDI (3 mm), dCXA (18°) and dPbC2 (3 mm). No predictor of cranio-cervical mobility was found in static neutral assessment.

CONCLUSIONS: This study distinguished 2 groups of patients, according to their CCJ mobility, with cut-off for dBDI, dCXA and dPbC2. Further studies comparing our findings with healthy controls or with a standardized modality (e.g. dynamic radiographs) are needed to assess if these criteria are predictors of cranio-cervical instability.

Keywords: Cranio-cervical instability, Dynamic MRI, Morphometric parameters, Children

PF-025

Spine

Timing of clinical and intraoperative neurophysiological monitoring (IONM) recovery after termination of pediatric spinal deformity surgery due to loss of IONM signals: When is it safe to return to the OR?

Richard C E Anderson¹, Travis S Crevecoeur², Rajiv R Iyer⁶, Hannah E Goldstein⁷, Lawrence G Lenke², Benjamin D Roye², Michael G Vitale², Benjamin Kennedy³, Patrick Cahill³, Lindsay Andras⁴, David Skaggs⁴, Alex Powers⁵

¹New York University, New York, USA

²Columbia University, New York, USA

³Children's Hospital of Philadelphia, Philadelphia, USA

⁴Children's Hospital of Los Angeles, Los Angeles, USA

⁵Wake Forest University, Winston-Salem, USA

⁶University of Utah, Salt Lake City, USA

⁷University of Washington, Seattle, USA

BACKGROUND AND AIM: IONM is used to reduce the risk of spinal cord injury during pediatric spinal deformity surgery. Significant reduction or loss of IONM potentials may lead the surgeon to abort the case. The goal of this study is to investigate the correlation between clinical and IONM recovery after aborted cases and help determine when it is safe to return to the operating room.

METHOD: A multicenter, retrospective study of pediatric patients undergoing spinal deformity surgery was conducted whose surgery was aborted due to a significant reduction or loss of IONM potentials. Data are still being collected, with analysis of 45 patients at this time. Baseline data, operative reports, clinical outcomes, and IONM data were analyzed to investigate the relationship between IONM loss, clinical outcome, and clinical and IONM recovery.

RESULTS: All patients had partial or complete loss of MEPs. 24/45 patients had loss of SSEPs. At the end of the aborted surgery, IONM potentials returned completely in 18/45 of patients, partially in 24/45, and no return in 3/45. Immediately post-operatively, 17/45 of patients developed new weakness, but only 9/45 had weakness > 72 h. Upon return to the OR, only 7/45 had insufficient signals to proceed with surgery. Overall, patients who had complete neurological recovery within 24 h were able to return to the OR at an average of one week with complete return of their IONM potentials. However, patients that required > 72 h for complete neurological recovery averaged greater than one month before return of monitorable IONM signals.

CONCLUSIONS: Significant reduction or loss of IONM signals can occur during pediatric spinal deformity surgery. These preliminary data suggest there is a correlation between the time of clinical recovery and IONM recovery. Additional data from this study will further clarify this association and help determine the safest time for returning to the operating room.

Keywords: Spine, Intraoperative neuromonitoring, SSEPs, MEPs, Spinal cord injury, Scoliosis

PF-026

Spine

Bony Anatomy of Foramen Magnum in Achondroplasia Patients: A CT based Comparison with Age-matched Controls and FGFR3 craniosynostosis syndromes

Catherine Zhang¹, Felice D'arco², Alessandro Borghi³, Moira Cheung⁴, Melita Irving⁵, Dominic Thompson¹

¹Department Of Neurosurgery, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom

²Department of Neuroradiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom

³UCL Great Ormond Street Institute of Child Health & Craniofacial Unit, London, UK

⁴Department of Paediatric Endocrinology, Evelina London Children's Hospital, London, UK

⁵Department of Clinical Genetics, Guy's and St Thomas' NHS Foundation Trust, London, UK

BACKGROUND AND AIM: Achondroplasia is the commonest non-lethal skeletal dysplasia, caused by FGFR3 mutation which accelerates endochondral growth plate ossification at the skull base. Foramen magnum stenosis is a well recognized complication of achondroplasia, however the bony anatomy and patterns of suture fusion have not been widely quantified. We evaluated the anatomy and fusion patterns of achondroplasia foramen magnum score (AFMS) 4 patients using pre-operative CT scans, and compare these with age-matched control patients and other FGFR3 craniosynostosis conditions.

METHOD: Pre-operative CT scans of AFMS 4 patients who underwent foramen magnum decompression were used, and compared with age-matched controls, Muenke and Crouzon Syndrome with Acanthosis Nigricans (CSAN) patients. Measurements obtained include: sagittal diameter (SD), transverse diameter (TD), foramen magnum area, opisthion thickness (Fig. 1). Anterior and posterior interoccipital synchondroses (AIOS and PIOS) were assessed and graded by extent of fusion.

RESULTS: 23 achondroplasia, 23 controls, 20 Muenke and 15 CSAN CT scans were used to obtain measurements. Achondroplasia had significantly smaller SD and TD compared with other groups (p < 0.0001), with 3.4 times smaller surface area compared with control group (Fig. 2). CSAN had the thickest average opisthion (9 mm), followed by achondroplasia (6.9 mm); both were significantly higher than Muenke and Control. All FGFR3 groups had higher PIOS fusion grades compared with controls, however achondroplasia patients had the highest fusion grades of all groups and this included both PIOS and AIOS (Fig. 3). Distinct bony opisthion spurs were seen in achondroplasia patients, giving rise to characteristic crescent and clover shapes (Fig. 4).

CONCLUSIONS: Patients with AFMS grade 4 achondroplasia have significantly reduced foramen magnum dimensions compared with control, Muenke and CSAN patients. This is associated with premature fusion of AIOS and PIOS. The presence of a bony opisthion spur also contributes to foramen magnum stenosis and its associated morbidity and mortality in achondroplasia patients.

Keywords: Achondroplasia, Foramen magnum, FGFR3, Foramen magnum stenosis

PF-027

Global Pediatric Neurosurgery

Pediatric neurosurgery fellowship program-an academic and public health join venture in Chile a 20 years experience

Sergio R Valenzuela ^1,2

¹Pediatric Neurosurgery Service, Dr Asenjo Neurosurgical Institute, Santiago,Chile

²Neurological Sciences Department, University of Chile, Santiago, Chile

BACKGROUND AND AIM: Our 20 years experience with a pediatric neurosurgical post graduate education program (fellowship) at the Dr Asenjo Neurosurgical Institute pediatric neurosurgical service and Neurological sciences department of the University of Chile is presented.

METHOD: The academic program, clinical objectives, financial source and technical abilities ara evaluated as well as the public health impact on children neurosurgical care in Chile.

RESULTS: The actual geographical distribution of pediatric neurosurgery facilities and neurosurgeons with full or partial dedication is compared with the previous situation in 2000 before this program started and the positive effect of it in the reference, counter reference and primary care of patients.

CONCLUSIONS: This presentation shows the great utility of having a post graduate program to enhance neurosurgical pediatric specific knowledge and abilities for general post graduated neurosurgeons working in places and cities far from the main neurosurgical centers in a very long country with long distances between mayor cities and difficult transfers and references or weather difficult conditions.

Keywords: Fellowship-pediatric-neurosurgical-children-care-reference

PF-028

Global Pediatric Neurosurgery

Nonsyndromic craniosynostosis in Vietnam: initial surgical outcomes of subspecialty mentorship

Can Dang Do Thanh

Department of Neurosurgery, University of Medicine and Pharmacy at Ho Chi Minh city, Vietnam; Department of Neurosurgery, Children's Hospital No 2, Ho Chi Minh City, Vietnam

BACKGROUND AND AIM: There is a global deficit of pediatric neurosurgical care, and the epidemiology and overall surgical care for craniosynostosis is not well characterized at the global level. This study serves to highlight the details and early surgical results of a neurosurgical educational partnership and subsequent local scale-up in craniosynostosis correction.

METHOD: A prospective case series was performed with inclusion of all patients undergoing correction of craniosynostosis at Children’s Hospital 2, Ho Chi Minh City, Vietnam, between January 1, 2015, and December 31, 2019.

RESULTS: A total of 76 patients were included in the study. The group was predominantly male, with a male-to-female ratio of 3.3:1. Sagittal synostosis was the most common diagnosis (50%, 38/76), followed by unilateral coronal (11.8%, 9/76), bicoronal (11.8%, 9/76), and metopic (7.9%, 6/76). The most common corrective technique was anterior cranial vault remodeling (30/76, 39.4%) followed by frontoorbital advancement (34.2%, 26/76). The overall mean operative time was 205.8 ± 38.6 min, and the estimated blood loss was 176 ± 89.4 mL. Eleven procedures were complicated by intraoperative durotomy (14.5%, 11/76) without any damage of dural venous sinuses or brain tissue. Postoperatively, 4 procedures were complicated by wound infection (5.3%, 4/76), all of which required operative wound debridement. There were no neurological complications or postoperative deaths. One patient required repeat reconstruction due to delayed intracranial hypertension. There was no loss to follow-up. All patients were followed at outpatient clinic, and the mean follow-up period was 32.3 ± 18.8 months postoperatively.

CONCLUSIONS: Surgical care for pediatric craniosynostosis can be taught and sustained in the setting of collegial educational partnerships with early capability for high surgical volume and safe outcomes. In the setting of the significant deficit in worldwide pediatric neurosurgical care, this study provides an example of the feasibility of such relationships in addressing this unmet need.

Keywords: Global pediatric neurosurgery, Craniosynostosis

PF-029

Other

Perinatal features of myelomeningocele patients after folate fortification in Costa Rica, a 25 year experience

Adrian Caceres¹, Ana Laura Jimenez Chaverri², Paula Alpizar Quiros³, Juan Luis Segura Valverde¹, Justiniano Zamora Chaves¹, Ariadnna Caceres Alan²

¹Neurosurgery Division, Spina Bifida Clinic, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

²General Pediatrics, Spina Bifida Clinic, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

³Nursing division, Spina Bifida Clinic, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

BACKGROUND AND AIM: 2021 marked the 30 anniversary of the landmark clinical trial by the British Medical Research Council Vitamin Study unequivocally demonstrating that folic acid prevents spina bifida and anencephaly, two serious neural tube defects. Costa Rica started its folate staple food fortification program in 1997 with a dramatic response in the decrease of spina bifida cases (74%) that has been sustained with minimal variations over the last 25 years.

METHOD: A retrospective analysis of the database from the spina bifida clinic allowed to determine the gestational age, delivery method and time to myelomeningocele closure and shunt insertion in those patients who required CSF diversion. Additional information regarding the size of the spina bifida defect, neurological level at birth, the presence of kyphosis and symptomatic Chiari were determined.

RESULTS: 396 patients with complete medical records were analyzed, 47% were male and 53% were female. Gestational age at birth was 39 weeks. 57% were delivered vaginally vs 43% cesarean Sect. 18% were paraplegic, 62% were L3, 9%L5, 11% sacral. Defect size was > 5 cm in 23%, 3–5 cm in 67% < 3 cm in 9% and 1% were non closable rachischisis. There were 2 patients with severe kyphosis and 6 patients (1.5%) with symptomatic Chiari at birth. Average time to closure was 8–12 h. in 17%, 12–24 h. in 72% and 24 to 48 h. 11%. Average time to shunt insertion was 8.7 days. Perinatal mortality was seen in 9 patients who harbored major congenital defects.

CONCLUSIONS: Folate fortification of food staples including wheat, maize, rice and dairy products have been instrumental in decreasing not only the rate but the clinical impact in patients born with myelomeningocele, while kyphosis and symptomatic Chiari are very low, the presence of hydrocephalus requiring shunting is still present, however there was a timely management of defect closure and shunt insertion.

Keywords: Spina bifida, Folate fortification, Hydrocephalus, Symptomatic chiari, Prevention, Surgery

PF-030

Global Pediatric Neurosurgery

Global pediatric neurosurgery: pilot in developing a multidisciplinary pediatric epilepsy surgery program in Uganda

Emmanuel Wegoye¹, Humphrey Okechi¹, Erik Padilla², Mariana Vincenteno², Khrystyna Moskalyk², Jeffrey Raskin², Michael Decuypere², Roxanna Garcia², Sandi Lam²

¹Pediatric Neurosurgery, CURE Uganda Hospital, Mbale, Uganda

²Department of Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, USA; Division of Pediatric Neurosurgery, Lurie Children's Hospital, Chicago, USA

BACKGROUND AND AIM: Epilepsy is the most common neurologic condition in the world, with a disproportionate burden of disease in low and middle income countries. Drug-resistant epilepsy patients with lesional epilepsy have the chance of a cure by surgery. We aimed to establish a global neurosurgery pilot program to develop an epilepsy surgery program at a pediatric hydrocephalus surgery training center in subSaharan Africa.

METHOD: An established, accredited electroencephalography training program was modified for web-based, real-time video-conferencing, and hands-on training. Development, implementation, and preliminary results of this pilot program to diagnose, identify, and treat pediatric patients with drug-resistant epilepsy were tracked and descriptive narrative provided.

RESULTS: Through the global initiatives program by ASET—The Neurodiagnostic Society, online educational modules for electroencephalography training were donated for a cohort of 10 participants in Mbale, Uganda. EEG instructors in an accredited apprenticeship training program in Chicago, USA taught in the interactive modified Zoom-based curriculum over 6 months. Weekly knowledge and skills assessments were conducted for EEG recording, troubleshooting, and interpretation. Ugandan patients for epilepsy surgery conference discussion were identified, prepared, and discussed in weekly epilepsy conference with the Chicago partner program.

A local needs assessment revealed > 500 patients on anti-seizure medications in need of EEG One pediatric neurologist in this country of 24 million population works 7 h away. These gaps were addressed with the arrangement and training above, with continuing web-based peer mentorship and weekly multidisciplinary epilepsy surgery conference discussion. Metrics of the process of surgical candidate identification, intervention, and epilepsy outcomes are tracked over time.

CONCLUSIONS: Global pediatric neurosurgery extends to development of a scalable, sustainable, peer-mentored pediatric epilepsy surgery program. The work is ongoing for knowledge and skill transfer: such a model holds potential to address some of the disease burden of epilepsy and help elevate quality of life for patients, families, and communities.

Keywords: Epilepsy, Epilepsy surgery, Program development, Multidisciplinary, EEG, Global health

PF-031

Global Pediatric Neurosurgery

Pediatric Craniopharyngioma Management Modalities and Outcomes Across the Globe

Busha Hika, BS, Alan Tang, BA, Olivia Prosak, BS, Joseline Haizel Cobbina, MBChB, MPH, Michael Dewan, MD, MSCI

Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN 37,232–8605 USA

BACKGROUND AND AIM: Pediatric craniopharyngiomas (CP) are challenging lesions with wide variations in treatment approach. Limited controlled data and variable surgical and oncologic capacity worldwide result in disparate treatment regimens. Here, we sought to compare management strategies for CP across global regions and income groups.

METHOD: A systematic literature search was performed for pediatric craniopharyngioma articles published in PubMed between 2000 and 2022. Patient demographics, tumor characteristics, treatments, and outcomes were extracted and compared across different income-level countries and geographic regions.

RESULTS: Twenty-nine articles with 2270 CP cases from six continents and 26 countries met the inclusion criteria and were analyzed. All but two articles were from high-income countries (HIC) or upper middle-income (UMIC) (27, 93%). 1762 children (77%) were from HIC, 193 (8.5%) from UMIC, and 199 (8.8%) from lower middle-income (LMIC); there were no studies from low-income countries (LIC). In HIC, 56% of patients underwent surgery only, 2.4% underwent radiation only, and 35% underwent surgical resection followed by radiation therapy (RT). In UMIC, 64% underwent surgery only and 15.5% underwent surgical resection followed by RT. In LMIC, 61% underwent surgery only, 1% radiation only, and 39% surgical resection followed by RT. Intracystic therapy was infrequently reported and differed across time epochs, not income groups: bleomycin was used in manuscripts published before 2015, while interferon was used in reports published after 2016. Tumor progression was seen in 48% and 31% of cases in LMIC and UMIC, respectively, compared to 10% in HIC (p-value 0.02).

CONCLUSIONS: A paucity of data from LMIC/LIC precluded a reasonable comparison of treatment modalities between high- and low-income settings, which calls for action regarding the reporting of how such patients are treated. HIC utilized more conservative approaches with favorable outcomes than UMIC, with fewer resections (53% vs 90%). Other factors, other than financial resources, may explain differences in CP management among HIC/UMIC.

Keywords: Global neurosurgery, Pediatric, Craniopharyngioma, Treatment Outcome, Worldwide

PF-032

Global Pediatric Neurosurgery

Impact of the COVID-19 pandemic on pediatric neurosurgical care in a developing country setting

Raquel Queiroz Sousa Lima¹, Vitória Cristina Almeida Flexa Ribeiro¹, Gabrielle Benevides Lima¹, Patrícia Pereira De Andrade¹, Carlos Eduardo Barros Jucá²

¹Universidade de Fortaleza (UNIFOR), Fortaleza, Brazil

²Department of Pediatric Neurosurgery, Hospital Infantil Albert Sabin (HIAS), Fortaleza, Brazil; Universidade de Fortaleza (UNIFOR), Fortaleza, Brazil

BACKGROUND AND AIM: The aim of this study was to identify the impact of the coronavirus pandemic on a reference center for pediatric neurosurgery in Brazil’s Northeast, regarding the number and types of procedures performed before and after the COVID-19 pandemic onset, identifying the main losses to children’s neurosurgical assistance.

METHOD: Retrospective, cross-sectional study of neurosurgical procedures performed in a reference pediatric hospital in Northeast Brazil between 2017 and 2021. Data were obtained from surgical block records and were assessed according to the type of procedure. The impact of COVID-19 pandemic was assessed by comparison between pre-pandemic period and pandemic period. Analysis of the most frequent canceled operations in 2020 was performed.

RESULTS: 1550 interventions in the pre-pandemic period (from 2017 to 2019, with a yearly increase of 6%) and 941 surgeries in the pandemic period. Comparison between 2019 and 2020 showed 551 and 493 respectivelly (10.5% reduction in a previous scenario of 6% yearly increase). When comparing two biannual periods, 2018–2019 and 2020–2021, there was a decrease in the total amount of surgeries (1.068 to 941—11,9%), mainly craniostenosis (19 to 13—31,5%), brain tumor (116 to 85—26,7%) and dysraphism (45 to 38—15,5%). Most frequently cancelled procedures were elective surgeries: closed dysraphism (30 to 17—43.3%), craniostenosis (10 to 6—40%) and tumors (48 to 41—14.6%).

CONCLUSIONS: In the context of a pediatric neurosurgery service in a developing country, which was passing through a transition from low complexity procedures to higher complexity ones, the COVID-19 pandemic caused a decrease in the total amount of interventions, representing a pushback in the previous trend. Pandemic had a negative influence in the number of elective procedures and lead to an important social negative impact on children care.

Keywords: Pediatric neurosurgery, Neurosurgery, Covid-19 pandemic, Covid-19

PF-033

Global Pediatric Neurosurgery

Update on Global Pediatric Neurosurgery

Nelci Zanon¹, Eylem Ocal², Martina Messing Jünger³, Suchanda Battacharjee⁴, Nabila Taghlit⁵, Wirginia Maixne⁶, Milagros Niquen Jimenes⁷

¹Nelci Zanon, Pediatric Neurosurgeon, Universidade Federal de São Paulo: Sao Paulo, São Paulo, Brazil

²Eylem Ocal, Pediatric Neurosurgeon, 1 Children’s Way Slot#838 Little Rock, AR, 72,202—USA

³Martina Messing—Jünger, Pediatric Neurosurgeon, Head of neurosurgery Chefärztin der Abteilung Neurochirurgie Zentrum für Kinderchirurgie,—orthopädie und—neurochirurgie Asklepios Klinik—Arnold—Janssen—Straße 29 53,757 Sankt Augustin—Germany

⁴Suchanda Battacharjee, Neurosurgeon Nizams Institute of Medical Sciences (NIMS), Panjagutta, Hyderabad—India

⁵Nabila Taghlit, Pediatric Unit of Neurosurgery, Specialized Hospital in Neurosurgery Ali AIT DIR, Algiers, Algeria; Algeri

⁶Wirginia Maixner, Neurosurgeon at t he Royal Children's Hospital Melbourne 50 Flemington Road Parkville Victoria 3052 Australia

⁷MilagrosNiquen Jimenez, Medical Student, Facultad de Medicina Alberto Hurtado, Universidad Peruana Cayetano Heredia, Lima, Peru

BACKGROUND AND AIM: Review on the Pediatric Neurosurgery background, creation of pediatric neurosurgical societies, current status and futures perspectives.

METHOD: The co-authors, from each continent, update the information’s from the local Pediatric Neurosurgery Societies and publications. The major difficulty was to find who is a pediatric neurosurgeon between the general neurosurgeons. The pediatric neurosurgery is still not recognized "officially" as a subspecialty in several countries.

RESULTS: In Europe, no official specialist degree for pediatric neurosurgeons exists. So far there is also no unified education system that defines an European standard.

In Australia, training in pediatric neurosurgery is supervised through the Neurosurgical Society of Australasia Training Board, regulated by the Royal Australasian College of Surgeons.

The lack of neurosurgeons in Africa led to a deficit in management of pediatric neurosurgical diseases except in North Africa (Morocco, Algeria, Tunisia and Egypt) and the Republic of South Africa. There are very few countries where there are pediatric neurosurgeons.

In Latin America, until the 1990's the neurosurgeons were seeking the pediatric neurosurgery fellowship training in Europe or in the USA. Nowadays, there are pediatric neurosurgery training centers in the large cities in several countries.

In USA, the Accreditation Council for Pediatric Neurosurgical Fellowships was created in 1992 to oversee and regulate pediatric neurosurgical training /fellowship programs in USA and Canada. The American Board of Pediatric Neurological Surgery is a nonprofit corporation that is now a well- established and accepted certifying body, and has become the standard accreditation authority for pediatric neurological surgery in the United States and Canada.

CONCLUSIONS: The challenge of pediatric neurosurgery starts on a basic level. Around 51 million births remain unregistered every year in LMIC according to the UNICEF. Much more work are waiting for this specialty.

Keywords: Pediatric neurosurgery, Training centers, Pediatric neurosurgery certification, Global neurosurgery

PF-034

Other

Craniosynostosis surgery: Vietnamese experiences

Truc Trung Vu¹, Anh Mai Bui², Ha Hong Nguyen², Manh Huy Bui³, Hung Manh Ngo³, He Van Dong³

¹Department of Maxillofacial-Platic-Aesthetic Surgery, Viet Duc University Hospital, Hanoi, Vietnam; Department of Plastic Surgery, Hanoi Medical University, Hanoi, Vietnam; Department of Oral and Maxillofacial Surgery, University of Medicine and Pharmacy, Vietnam National University, Hanoi, Vietnam

²Department of Maxillofacial-Platic-Aesthetic Surgery, Viet Duc University Hospital, Hanoi, Vietnam

³Department of Neurosurgery, Viet Duc University Hospital, Hanoi, Vietnam

BACKGROUND AND AIM: Up to now, there are currently no guidelines for the optimum age of surgical treatment for craniosynostosis. In Vietnam, there are few surgical center can perform that kind of surgery. It required a team work, machines, and some deep specialty like neurosurgery, plastic surgery, anesthesiologist… Recently, age of patient at time of surgery is getting younger. The goal of this study was to review the current application and status of craniosynostosis surgery in Vietnam.

METHOD: A cross sectional study was performed at Viet Duc University Hospital—the biggest surgical center in Hanoi, Vietnam to evaluate all craniosynostosis cases which were suffered from surgical treatment from 2016 to 2021.

RESULTS: A total 21 cases of craniosynostosis were included in this study. There were 12 cases with single suture premature and 8 cases with multiple suture premature. At time of surgery, the youngest patient was 3 months and oldest patient is 10 years old (20.3 months in average). The patients were divided to two groups: under 1 year old (younger group) and over 1 year old (older group). All patient was smoothly recovery without any major complications and the satisfaction of younger groups is significant higher comparing with older group (interview patient's family members).

CONCLUSIONS: Although, craniosynostosis surgery can be safely performed at early age but the beneficial is still unknown. Our study showed that the surgical results and complications are similar at any age but the satisfaction of younger groups is significant higher. The authors recommend that future research use agreed-upon parameters for: age-at-surgery cut-offs, follow-up times, and outcome measures.

Keywords: Craniofacial, Craniosynostosis, Neurodevelopmental, Surgery, Timing

PF-035

Global Pediatric Neurosurgery

Treatment of Sagittal Synostosis in Children Older than Two Years of Age—Long-term Follow-up

Hamilton Matushita, Daniel Dante Cardeal, Felipe Hada Sanders, Vitor Nagai Yamaki, Renata Harumi Gobato Yamashita, Manuel Jacobsen Teixeira

Pediatric Neurosurgery, Hospital das Clinicas, São Paulo University, São Paulo, Brazil

BACKGROUND AND AIM: Surgical techniques for correcting sagittal synostosis are very diverse and controversial, especially for children under one year. However, there is a consensus for children over two years of age that reconstructive techniques of the cranial convexity are necessary. This work aims to evaluate the surgical results of children operated on over two years of age, using a non-radioactive method, since excellent agreement has been found between the direct (anthropometric) and indirect (cephalometric) measurements.

METHOD: We report 46 consecutive cases of children with sagittal synostosis, older than two years of age, who underwent surgical treatment. Since 2004 we have followed all patients with craniosynostosis, with anthropometric measurements, during the pre-and post-operative follow-up.For sagittal synostosis, the primary measure was Cephalic Index. The measurements were performed in the hospital outpatient clinic by members of the pediatric neurosurgery team using an anthropometric caliper (Paleo-Tech).

RESULTS: The surgical treatment techniques applied to these patients were: Total reconstruction in 19, partial reconstruction (parietal and frontal) in 16 and partial reconstruction (parietal and occipital) in 11. The mean age at surgery was 34,2 months (24–84 months). The mean cephalic index (CI) in the pre-op was 0,64 (range 0,58–0,70), and at the postoperative period up to 3 months follow-up was 0,74 (range 0,69–0,84). The average percentage of improvement was 15% (range 1%—27%) (p < 0,05). The mean follow-up was 47,8 months (range 24 – 94 months). After the first measure of CI during three months of surgery, the percentage of variation ranged from -1% to + 1%, indicating stabilization of the CI.

CONCLUSIONS: Cranial morphology can be improved in late surgical correction of sagittal synostosis.

The final morphological results may be the early measurements taken up to 3 months of post-op, as no improvement of the cephalic index was seen after this period.

Keywords: Sagittal synostosis, Scaphocephaly, Craniosynostosis, Cephalic index, Anthropometric measurement

PF-036

Innovation and technology

Noninvasive nanotherapy for Crouzon syndrome based on allele-specific FGFR2 knockdown through recombinant human ferritin nanocarrier

Federica Tiberio¹, Martina Salvati¹, Lorena Di Pietro¹, Elisabetta Falvo², Luca Massimi³, Giada Tisci⁴, Pierpaolo Ceci², Ornella Parolini¹, Alessandro Arcovito⁵, Gianpiero Tamburrini³, Wanda Lattanzi¹

¹Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, Rome, Italy

²Istituto di Biologia Molecolare e Patologia, Consiglio Nazionale delle Ricerche, Rome, Italy

³Dipartimento Scienze dell'invecchiamento, neurologiche, ortopediche e della testa-collo, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy

⁴Dipartimento di Scienze Biochimiche, Università La Sapienza, Rome, Italy

⁵Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche, e Perioperatorie, Università Cattolica del Sacro Cuore, Rome, Italy

BACKGROUND AND AIM: Crouzon syndrome (CS) is a rare craniofacial malformation caused by gain-of-function mutations in the Fibroblast Growth Factor Receptor 2 (FGFR2) gene and characterized by craniosynostosis as a hallmark. The treatment is based on multiple surgeries to release the skull constraint that impairs the child’s brain growth. The aim of this project is to develop a noninvasive therapy for CS using allele-specific siRNAs targeting the mutant FGFR2 allele, delivered by recombinant human ferritin (HFt) as a highly biocompatible nanocarrier to restore FGFR2 signaling and the fusion-timing pattern of sutures.

METHOD: Calvarial mesenchymal stromal cells (CMSCs) were isolated from calvarial tissue from FGFR2 mutation-positive CS patients. A set of siRNA specifically targeting the mutant FGFR2-alleles of each patient was designed and tested in patient cells. The efficiency of each siRNA was evaluated through real time PCR. The expression of the receptor of ferritin CD71 in CMSCs was investigated using real time PCR. CMSCs were incubated with fluorescein isothiocyanate-labeled HFt and analysed using fluorescence microscopy. siRNAs have been encapsulated within ferritin cavity performing pH-dependent procedure and the complexes were tested in CMSCs using Incucyte Live-cells analysis system.

RESULTS: Gene expression analysis allowed identifying specific siRNAs with differential knockdown efficiency between wild-type and mutant FGFR2 alleles in CMSCs derived from CS patients. Expression analysis revealed that CD71 was up-regulated during osteogenic differentiation of CMSCs. Fluorescence microscopy showed an efficient internalization of HFt within CMSCs cytoplasm. Preliminary results with HFt-based nanoparticles showed so far that, though siRNAs can be encapsulated in HFt, their intracellular trafficking is poorly detectable.

CONCLUSIONS: Our data suggested that allele-specific FGFR2 knockdown by siRNA represents a desirable strategy to silence FGFR2 mutant allele in CS patients. We demonstrated that HFt is suitable for delivery in CMSCs. Future studies aim to optimize the intracellular trafficking of HFt-siRNAs construct.

Keywords: Craniosynostosis, Gene silencing, Mesenchymal stromal cells, Nanotherapy, Ferritin

PF-037

Global Pediatric Neurosurgery

Autism-like traits in children with trigonocephaly

Daniela Pia Rosaria Chieffo¹, Federica Moriconi¹, Valentina Arcangeli¹, Cristina Giansanti¹, Sofia Vannuccini¹, Federico Bianchi³, Paolo Frassanito³, Luca Massimi², Gianpiero Tamburrini²

¹Clinical Psychology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS Rome Italy (A)

²Università Cattolica Sacro Cuore Rome Italy (B)

³Pediatric Neurosurgery, Fondazione Policlinico Universitario A. Gemelli IRCCS Rome Italy (C)

BACKGROUND AND AIM: Children with non syndromic trigonocephaly might present cognitive and behavioural disorders more frequently than children affected by other forms of single suture craniosynostosis and, independently from the surgical treatment and the age it is performed, cognitive disorders might persist during the child growth. The aim of the present study has been to describe the specific cognitive and behavioural profile of children with trigonocephaly and its clinical course according to preoperative findings.

METHOD: All children operated on for a trigonocephaly between Jan 2015 and Dec 2020 were included. A complete set of neurocognitive and behavioural tests was administered in all cases before surgery (0), 6 months (T1) and 1 year (T2) after surgical treatment, at 3 years of life (T3) and at time of their entry to primary school (T4).

RESULTS: 84 children with trigonocephaly were included in our study. At diagnosis (T0) 10/84 ( 11%) children had a general cognitive development below normal range. The scales with higher level of impairment were those inherent to personal-social areas (12%) which are compatible with behavioral problems, and hearing skills (19%).

At 1 year 8/12 (67%) children who presented disorders inherent to personal social areas at diagnosis developed autistic traits. An early rehabilitation allowed an improvement only in 2 of these cases.

CONCLUSIONS: An impairment at diagnosis in personal social areas skills is highly predictive of the development of autism spectrum traits in children with metopic synostosis. These traits might persist over time in spite of an early rehabilitation programme suggesting a congenital functional impairment of the frontal regions, independent from the release of the local constriction due to the premature fusion of the metopic suture.

Keywords: Trigonocephaly cognitive autism rehabilitation surgery development

PF-038

Other

Clinical interest of molecular study in cases of isolated midline craniostenosis

Federico Di Rocco¹, Sofia Guernouche¹, Massimiliano Rossi², Alexandru Szathmari¹, Pierre Aurélien Beuriat¹, Julie Chauvel Picard³, Carmine Mottolese¹, Mathieu Vinchon¹, Isabelle Verlut¹, Corinne Collet⁴

¹Pediatric Neurosurgery Department, Craniosynostosis National Reference Center, Hôpital Femme Mère Enfant-Hospices Civils de Lyon,, Lyon, France

²Genetics Department, Competence centre for constitutional bone diseases, Hôpital Femme Mère Enfant-Hospices Civils de Lyon, Lyon, France

³Maxillofacial Surgery and Stomatology Department, Hôpital Femme Mère Enfant-Hospices Civils de Lyon, Lyon, France

⁴Genetics department of Robert Debré hospital-Paris University hospital, Paris, France

BACKGROUND AND AIM: An underlying mutation can be found in some cases in infants with an apparently isolated single suture synostosis. Our objective was to determine the molecular substratum in isolated sagittal and metopic craniosynostosis.

METHOD: Our cohort included all infants who presented an isolated midline synostosis (sagittal or metopic) who have been operated on at the craniosynostosis national reference center of Lyon University Hospital from 2018 to 2020. All patients presented a clinically and radiologically confirmed premature fusion of the sagittal or the metopic suture. Children with a teratogenic exposure were excluded as well as patients with clinical and radiological signs of syndromic craniosynostosis. All patients were examined by a multidisciplinary team including neurosurgeons, clinical geneticists and neuropsychologist.

RESULTS: Among 101 children tested, a total of 13 variants were found in 13 patients, in other words, 12.8% of the patients displayed a variant in genes known in craniosynostosis. We found 6 patients with a SMAD6 variants (4.6%), 2 in FGFR2 (1.5%), 2 in TWIST1 (1.5%), one in FREM1 (0.8%), one in ALX4 (0.8%) and one combination of variants in TCF12 and ALX4 (0.8%). All variants were detected at heterozygous level in genes associated with an autosomal dominant craniosynostosis. No homozygous or compound heterozygous genotypes were identified.

CONCLUSIONS: We found herein a high percentage of affected young children who carry SMAD6 variants especially in isolated trigonocephaly. Moreover, variants in other genes were also represented in midline craniosynostosis. The interpretation of their pathogenicity has to take into account the incomplete penetrance, usually observed in craniosynostosis.

Our results highlight the interest to realize molecular analysis in the context of isolated sagittal and/or metopic craniosynostosis to enhance understanding the physiopathology of midline craniosynostosis.

Keywords: Neurosurgery, Isolated midline craniostenosis, Molecular study

PF-039

Other

Secondary cranial suture fusion after craniosynostosis surgery: prevalence with different surgical methods

Fehid Habalrih¹, Sangjoon Chong², Jong Woo Choi³, Young Shin Ra²

¹Department of Neurosurgery, Asan Medical Center, Seoul, South Korea

²Department of Neurosurgery, Asan Medical Center and University of Ulsan College of Medicine, Seoul, South Korea

³Department of Plastic Surgery, Asan Medical Center and University of Ulsan College of Medicine, Seoul, South Korea

BACKGROUND AND AIM: Secondary suture fusion can develop after cranial surgery in children. The occurrence of secondary craniosynostosis (CS) of uninvolved suture after craniosynostosis surgery is retrospectively reviewed, with analyzing its relation to the surgical methods and the age at the time of surgery.

METHOD: A retrospective study of all non-syndromic craniosynostosis patients who underwent surgical management from 1995–2021. Patients were analyzed according to the age at the time of surgery and to the surgical methods, which are: 1- cranial vault reconstruction (CVR), 2- suturectomy and 3- distraction osteogenesis (DO). The occurrence of secondary CS was investigated on 3-D computed tomography scan with 1-year minimum follow-up. Surgical technique and age at the time of surgery were statistically analyzed. We reviewed our management to secondary CS patients.

RESULTS: Among 179 patients who underwent craniosynostosis surgery, 21 patients (11.7%) were found to have secondary craniosynostosis with mean follow up of 17-months interval. The most common secondary CS was sagittal suture (47.6%), it developed in 10 patients, followed by bicoronal suture 19% (4), unicoronal suture 14.4% (3) and bilambdoid suture 9.5% (2). Two patients developed multiple sutures fusion (9.5%). It occurred in 7.5% with cranial vault reconstruction, 8.9% with suturectomy and 15.6% with DO (p-value 0.326). There was no significant relation between the secondary CS and the age at the time of surgery (p-value 0.723). Only 2 patients with secondary CS required another surgery due to increased intracranial pressure. The first patient underwent CVR for bilambdoid CS and secondarily developed sagittal CS, then needed to have expansive CVR. The second patient underwent suturectomy for sagittal CS and developed secondary bicoronal CS and expansive DO was performed.

CONCLUSIONS: Secondary craniosynostosis is not uncommon and should be considered during follow up. Mostly, it doesn’t require surgical intervention unless increased intracranial pressure develops.

Keywords: Secondary, Craniosynostosis, Children, Cranial suture, Surgery

PF-040

Hydrocephalus

Optical neuromonitoring and volumetric imaging for early assessment of surgical efficacy in infantile hydrocephalus: a multi-center investigation

Ajay Rajaram¹, Rutvi Vyas¹, Taylor Vadset¹, Miriah Kemigisha Katungi², Chuan Heng Hsiao¹, Marvin Seruwu², Luis Neri Perez¹, Joshua Magombe², Brian Kaaya Nsubuga², Julia Tatz¹, Davis Natukwatsa², Moses Wabukoma², Mallory Peterson³, Esther Nalule², Michael Woglom¹, Rachel Lippman¹, Ronald Mulundo², Jennifer Queally⁴, Steven Schiff³, Aaron Fenster⁶, P. Ellen Grant⁵, Jason Sutin¹, Edith Mbabazi Kabachelor², Benjamin C Warf⁷, Pei Yi Lin¹

¹Division of Newborn Medicine, Boston Children’s Hospital; Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children’s Hospital, Boston, USA

²CURE Children's Hospital of Uganda, Mbale, Uganda

³Center for Neural Engineering, Pennsylvania State University, State College, USA.

⁴Department of Psychiatry, Boston Children’s Hospital, Boston, USA.

⁵Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children’s Hospital, Boston, USA; Department of Radiology, Boston Children’s Hospital, Boston, USA

⁶Robarts Research Institute, Western University, London, Canada

⁷Department of Neurosurgery, Boston Children’s Hospital, Boston, USA

BACKGROUND AND AIM: The prevalence and etiology of infantile hydrocephalus varies globally: America admits 39,000 patients annually [1], while sub-Saharan Africa sees over 100,000 new cases each year, most occurring post-infection. Traditionally, ventriculoperitoneal shunts are implemented to drain CSF from the ventricles but 40% fail within two years [2]. Endoscopic third ventriculostomy and choroid plexus cauterization (ETV/CPC), pioneered at CURE Children’s Hospital of Uganda (CCHU), is an effective, low-resource alternative to drain CSF while minimizing its production. ETV/CPC avoids a permanent fixture, requires less post-operative care, and has lower rates of infection [3]; however, early treatment failure remains a significant problem that is challenging to assess with imaging alone.

Biomedical optics offers non-invasive and cost-effective bedside monitoring of cerebral physiology. Frequency-domain near-infrared and diffuse correlation spectroscopy (FD-NIRS/DCS) can quantify cerebral blood flow (CBF) and metabolism, which have shown potential as early indicators of development/injury in premature infants and post-hemorrhagic hydrocephalus [4,5].

METHOD: Infants undergoing ETV/CPC at Boston Children’s Hospital (BCH) and CCHU were monitored pre-/post-operatively using FD-NIRS/DCS to quantify CBF and metabolism in six brain regions. CCHU subjects were imaged pre-/post-operatively with 3D-ultrasound and pre-operatively/6-months with CT to quantify brain tissue/ventricle volumes. BCH subjects were imaged pre-/post-operatively and at 6-months with MRI. Surgical failure was assessed at 6-months.

RESULTS: In 37 subjects at BCH significant post-operative increases in CBF and metabolism were found only for the failure-free cohort (n = 21); no change was observed in patients experiencing surgical failure (n = 16). At CCHU, outcome assessment is ongoing. Significant post-operative increases were observed for CBF and metabolism across all subjects (n = 43).

CONCLUSIONS: Optical brain monitoring has demonstrated strong potential for early prognosis and timely evaluation of surgical efficacy following ETV/CPC and could alter patient management surrounding the development and treatment of infantile hydrocephalus.

1) Simon, J.Neurosurg.Ped., 2008; 2)Kulkarni, J.Neurosurg.Ped, 2013; 3)Warf, J.Neurosurg.Ped., 2011; 4)Rajaram, Sci.Rep., 2022; 5)Rajaram, Brain Sci., 2020.

Keywords: Hydrocephalus, Optical neuromonitoring, Endoscopic third ventriculostomy and choroid plexus cauterization, Surgical efficacy, Volumetric imaging

PF-041

Hydrocephalus

ENdoscopic Lavage after IntraVEnticular haemorrhage in Neonates (ENLIVEN): Interim report from a randomized controlled trial

William Dawes, Sarah Olney, Malak Mohamed, Aswin Chari, Greg James, Kristian Aquilina

Department of Neurosurgery, Great Ormond Street Hospital

BACKGROUND AND AIM: Neuroendoscopic lavage (NEL) may improve outcomes in premature neonates with intraventricular haemorrhage (IVH). We report interim results from a single centre open label randomized controlled trial of NEL + ventriculosubgaleal shunt (VSGS) vs VSGS alone.

METHOD: All premature neonates with IVH undergoing VSGS were eligible for inclusion. NEL was performed using a flexible endoscope with lavage, gentle mobilization, aspiration of intraventricular clot and septostomy. The primary outcome was the rate of VP shunt insertion at 6 months’ corrected age. The trial was designed to detect a 40% reduction in shunt rate with 80% power.

RESULTS: To date, seventeen neonates have been recruited. Median gestational age at birth was 25.6 weeks (range 23.6–29.0). Median gestational age and weight at operation were 27.9 weeks (range 27.9–34.0) and 1090 g (range 800–1660). Nine neonates were randomized to the NEL + VSGS arm, eight to the VSGS arm. There were no intra-operative complications. Median length of stay was 2 days in the NEL + VSGS arm and 2.5 days in the VSGS arm. VP shunt insertion was performed in 7/9 (78%) in the NEL + VSGS arm and 6/8 (75%) of the VSGS arm. At last follow-up, 4/7 (57%) in the NEL + VSGS arm and 3/6 (50%) in the VSGS arm had undergone shunt revision. At median age of 2.9 years (range 1.5–4.2), 5/8 (63%) in the NEL + VSGS arm and 4/7 (57%) in the VSGS arm had a favourable developmental outcome.

CONCLUSIONS: This interim report from an open label randomized controlled trial shows that NEL is a safe procedure. Given the emerging evidence that NEL may have a positive impact on cognitive and developmental outcomes without affecting shunt rates, trials with robust developmental primary endpoints are warranted.

Keywords: Intraventricular haemorrhage, Hydrocephalus, Post-haemorrhagic hydrocephalus

PF-042

Hydrocephalus

Choice of valve in infant hydrocephalus: where to start?

Benjamin J. Hall¹, Conor Gillespie², Geraint J. Sunderland³, Elizabeth J. Conroy⁴, Dawn Hennigan¹, Michael D. Jenkinson², Benedetta Pettorini¹, Conor Mallucci¹

¹Alder Hey Children's Hospital NHS Foundation Trust, Liverpool, UK

²Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK

³Institute of Infection Veterinary and Ecological Sciences, University of Liverpool

⁴Liverpool Clinical Trials Centre, University of Liverpool, Liverpool, UK

BACKGROUND AND AIM: Infant hydrocephalus is the most common indication for ventriculoperitoneal (VP) shunts, with failure and revisions leading to significant patient morbidity, economic burden and increasing surgical workload. The aim of this paper was to review the use of different valve types in infants with hydrocephalus; attempting to determine whether an optimal valve choice exists for this patient cohort.

METHOD: We conducted (1) a retrospective review of data from the pivotal BASICS trial for infant patients (≤ 2 years) with hydrocephalus, (2) a separate, institutional cohort study from Alder Hey Children’s Hospital NHS Foundation Trust (England, UK, 2010–2018), and (3) a literature review for all studies describing valve types used (programmable vs. non-programmable, valve size, pressure). The primary outcome was 2-year revision not due to infection.

RESULTS: The BASICS data identified 391 infants, with no statistically significant difference in failure rates between gravitational (36.1% vs 30.5%, p = 0.294) and programmable subgroups at 24 months (29.6% vs 33.2%, p = 0.713). The institutional data did not reveal any significant difference in 2-year failure rate between fixed and programmable subtypes overall (25% vs 28.5%, p = 0.95), and after correction for shunts that had failed within 3 months of insertion (12.4% vs 22.6%, p = 0.2). Nineteen studies were included in the review. Most did not identify a superior valve choice between programmable and non-programmable, small compared to ultra-small, and differential pressure compared to flow-regulating valves. Five studies investigated a single-valve type without a comparator group.

CONCLUSIONS: There appears to be no difference in non-infective failure rates between valve subtypes. However, this is limited by a lack of direct comparison in the literature. Direct comparison via randomised trials is required to address the significant heterogeneity amongst the available treatment choices.

Keywords: Hydrocephalus, Ventricle-peritoneal shunt, valve, Infant

PF-043

Hydrocephalus

Endoscopic Third Ventriculostomy in Previously Shunted Patients

Brandon G Rocque¹, Hailey Jensen², Ron W Reeder², Abhaya V Kulkarni³, Ian F Pollack⁴, John C Wellons Iii⁵, Robert P Naftel⁵, Eric M Jackson⁶, William E Whitehead⁷, Jonathan A Pindrik⁸, David D Limbrick⁹, Patrick J Mcdonald¹⁰, Mandeed S Tamber¹⁰, Todd C Hankinson¹¹, Jason S Hauptman¹², Mark D Krieger¹³, Jason Chu¹³, Tamara D Simon¹⁴, Jay Riva Cambrin¹⁵, John R. W Kestle¹⁶, Curtis J Rozzelle¹

¹1Department of Neurosurgery, Children’s of Alabama, The University of Alabama at Birmingham, Birmingham, Alabama, USA

²Department of Pediatrics, University of Utah, Salt Lake City, Utah

³Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, Canada

⁴Department of Neurosurgery, UPMC Children’s Hospital of Pittsburgh, University of Pittsburgh, Pennsylvania

⁵Department of Neurosurgery, Vanderbilt University Medical Center; and Surgical Outcomes Center for Kids, Monroe Carell Jr. Children’s Hospital at Vanderbilt University, Nashville, Tennessee

⁶Department of Neurosurgery, The Johns Hopkins Hospital, Johns Hopkins University, Baltimore, Maryland

⁷Department of Neurosurgery, Texas Children’s Hospital, Houston, Texas

⁸Department of Neurosurgery, The Ohio State University College of Medicine, Columbus, Ohio

⁹Department of Neurosurgery, Washington University School of Medicine in St. Louis, Missouri

¹⁰Division of Neurosurgery, British Columbia Children’s Hospital, The University of British Columbia, Vancouver, British Columbia, Canada

¹¹Department of Neurosurgery, Children’s Hospital Colorado, Colorado Springs, Colorado

¹²Department of Neurosurgery, Seattle Children’s Hospital, University of Washington, Seattle, Washington

¹³Department of Neurosurgery, Children’s Hospital Los Angeles, University of Southern California, Los Angeles, California

¹⁴Department of Pediatrics, Children’s Hospital Los Angeles, University of Southern California, Los Angeles, California

¹⁵Division of Neurosurgery, Alberta Children’s Hospital, University of Calgary, Alberta, Canada

¹⁶Department of Neurosurgery, University of Utah, Salt Lake City, Utah

BACKGROUND AND AIM: Endoscopic Third Ventriculostomy (ETV) is an option for treatment of hydrocephalus, including for patients who have a history of previous treatment with cerebrospinal fluid shunt insertion (CSF shunt). The purpose of this study is to report the success of post-shunt ETV using a multi-center, prospective registry.

METHOD: Prospectively collected data in the Hydrocephalus Clinical Research Network Core Data Project were reviewed. Children who underwent ETV between 2008 and 2019 and had a history of previous treatment with a CSF shunt were included. A Kaplan–Meier survival curve was created for the primary outcome: time from post-shunt ETV to subsequent CSF shunt placement or revision. Univariable Cox proportional hazards models were created to evaluate for association between clinical and demographic variables and subsequent shunt surgery. Post-shunt ETV complications were also identified and categorized.

RESULTS: A total of 203 children were included: 57% male, 43% female; 74% White, 23% Black, 4% other race. The most common hydrocephalus etiologies were post-intraventricular hemorrhage secondary to prematurity (56, 28%) and aqueductal stenosis (42, 21%). ETV Success Score ranged from 10 to 80. Median age was 4.1 years. The overall success of post-shunt ETV at 6 months was 41%. Only report of a clear view of the basilar artery was associated with lower likelihood of failure (HR 0.43, 95% CI 0.23–0.82, p = 0.009). None of the following were associated with success: age at the time of post-shunt ETV, hydrocephalus etiology, sex, race, ventricle size, number of previous shunt operations, shunt infection, and use of external ventricular drainage.

CONCLUSIONS: Post-shunt ETV was successful in treating hydrocephalus, without subsequent need for a CSF shunt, in 41% of subjects, with a clear view of the basilar artery the only variable significantly associated with success. Complications occurred in 22%. ETV is an option for treatment of hydrocephalus in children who have previously been shunted.

Keywords: Hydrocephalus, Ventriculoperitoneal shunt, Endoscopic third ventriculostomy, ETV revision, Hydrocephalus Clinical research network

PF-044

Hydrocephalus

Prolonged clearance of cerebrospinal fluid (CSF) ferritin and bilirubin following preterm severe intraventricular hemorrhage (IVH) predicts post-hemorrhagic hydrocephalus

Kelly Mahaney¹, Venkata Ravindra Pothineni¹, Zhe Wang³, Jahanbanoo Shahryari³, Jayakumar Rajadas³, Diego Morales², David Limbrick, Jr.², Summer Han⁴, Jennifer Strahle²

¹Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA

²Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO

³Advanced Drug Delivery and Regenerative Biomaterials Laboratory, Stanford University School of Medicine, Stanford, CA

⁴Quantitative Sciences Unit, Stanford Center for Biomedical Informatics Research (BMIR), Stanford University, Stanford, CA

BACKGROUND AND AIM: Post-hemorrhagic hydrocephalus following severe intraventricular hemorrhage (IVH) is among the most devastating sequelae of premature birth. While many infants die during the birth hospitalization with hydrocephalus, among those that survive, early differentiation of post-hemorrhagic ventricular dilation that subsequently resolves from permanent hydrocephalus requiring a shunt has been challenging.

In this study we sought to determine if levels of CSF hemoglobin or hemoglobin degradation products from serial ventricular taps discriminate between neonates with post-hemorrhagic ventricular dilation following severe IVH and those with post-hemorrhagic hydrocephalus requiring a shunt.

METHOD: In this nested case–control study, CSF samples were collected from serial ventricular taps of 23 premature neonates with severe IVH and subsequent post-hemorrhagic ventricular dilation at St. Louis Children’s Hospital and Lucille Packard Children’s Hospital. CSF samples were analyzed for iron levels, quantified by mass spectrometry, and hemoglobin, bilirubin, ferritin, and heme oxygenase-1 (HO-1) levels quantified by ELISA. The composite outcome of “post-hemorrhagic hydrocephalus or death” was met by placement of a ventriculoperitoneal shunt or death during the neonatal period with hydrocephalus (determined by severe ventriculomegaly on imaging).

RESULTS: Fourteen patients developed post-hemorrhagic hydrocephalus or died with hydrocephalus during the neonatal period; 9 patients had resolved post-hemorrhagic ventricular dilation and did not require a shunt. Initial levels of CSF hemoglobin, iron, bilirubin, ferritin, and HO-1 did not differ between the two groups. However, infants that developed post-hemorrhagic hydrocephalus or died with hydrocephalus in the neonatal period had prolonged clearance of CSF bilirubin and ferritin compared to infants who did not require a shunt (11 vs. 8.5 weeks; 13 vs. 8.75 weeks respectively, p < 0.05).

CONCLUSIONS: Among preterm neonates with post-hemorrhagic ventricular dilation, earlier clearance of CSF ferritin and bilirubin may predict resolution of ventriculomegaly and lower risk of post-hemorrhagic hydrocephalus.

Keywords: Cerebrospinal fluid, Intraventricular hemorrhage, Ferritin, Bilirubin, Post-hemorrhagic ventricular dilation, Post-hemorrhagic hydrocephalus

PF-045

Hydrocephalus

Volumetric analysis in post-haemorrhagic ventricular dilatation: a retrospective cohort study

Matthew Kane¹, Jonathan O’muircheartaigh², Malak Mohamed¹, Cristine Sortica Da Costa³, William Dawes³, Gregory James³, Aswin Chari³, Kristian Aquilina³

¹UCL Great Ormond Street Institute of Child Health, London, UK

²King's College London Department of Forensic and Neurodevelopmental Sciences, London, UK

³Great Ormond Street Hospital, London, UK

BACKGROUND AND AIM: To identify the factors influencing brain volumes at term-equivalent age (TEA) and to determine how these brain volumes and other factors correlate with neurodevelopmental outcome (NDO) among infants with post-haemorrhagic ventricular dilatation (PHVD).

METHOD: This was a retrospective cohort study conducted in a single paediatric neurosurgical department in the UK.

The study included all preterm infants with PHVD who required ventriculosubgaleal shunt (VSGS) insertion at Great Ormond Street Hospital (GOSH) between January 2012 and December 2020. These infants received standardised management according to the local treatment protocol, with VSGS as the first-line temporising device.

Brain volumes were extracted from MRI scans performed at TEA using semi-automated segmentation. NDO was retrospectively classified using the grading system developed by Resch et al. (1996).

RESULTS: 84 infants with median gestational age of 26.00 weeks (range 23.14–33.71) and birth weight of 857.50 g (range 533–2500) were evaluated. 31 infants had segmented MRI scans at TEA (31–62 weeks post-menstrual age), while the remaining 53 infants had brain volumes entered via multiple imputation.

On multivariate analyses, cerebellar volume decreased by 12.75 mL (95% CI 7.61–17.90) among infants with sepsis and by 10.46 mL (95% CI 3.87–17.05) among those with multiloculated hydrocephalus. Deep grey matter (dGM) volume decreased by 0.09 mL (95% CI 0.04–0.15) per day of intubation and by 3.19 mL (95% CI 0.20–6.18) among infants requiring inotropes. Time from intraventricular haemorrhage to first VSGS insertion was a non-significant factor in the multivariate model for dGM volume (p = 0.102). Greater dGM volume was associated with reduced odd of adverse NDO at two-year follow-up (odds ratio 0.873; 95% CI 0.793–0.960).

CONCLUSIONS: dGM volume at TEA could provide a useful prognostic marker for NDO among infants with PHVD. Addressing modifiable factors that adversely influence dGM volume may improve outcomes for these infants.

Keywords: Hydrocephalus, Intraventricular haemorrhage, Neonate, Ventriculosubgaleal shunt, Brain volume, Neurodevelopmental outcome

PF-046

Hydrocephalus

A Standardised Protocol for Neuro-endoscopic Lavage for Post-haemorrhagic Ventricular Dilatation: A Delphi Consensus Approach

Saniya Mediratta, Aswin Chari, Kristian Aquilina

Department of Neurosurgery, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London, UK

BACKGROUND AND AIM: Neuro-endoscopic lavage (NEL) has shown promise as an emerging procedure for intraventricular haemorrhage (IVH) and post-haemorrhagic ventricular dilatation (PHVD). However, there is considerable variation with regards to the indications, objectives, and surgical technique in NEL. There is currently no randomised trial evidence that supports the use of NEL in the context of PHVD. This study aims to form a consensus on technical variations in the indications and procedural steps of NEL.

METHOD: A mixed methods modified Delphi consensus process was conducted between consultant paediatric neurosurgeons across the United Kingdom. Stages involved literature review, survey, focused online consultation, and iterative revisions until > 80% consensus was achieved.

RESULTS: Twelve consultant paediatric neurosurgeons from 10 neurosurgical centres participated. A standardised protocol including indications, a 3-phase operative workflow (pre-ventricular, intraventricular, post-ventricular) and post-operative care was agreed upon by 100% of participants. Case- and surgeon-specific variation was considered and included through delineation of mandatory, optional, and not recommended steps.

CONCLUSIONS: Expert consensus on a standardised protocol for NEL was achieved, delineating the surgical workflow into three phases: pre-ventricular, intraventricular, and post-ventricular, each consisting of mandatory, optional, and not recommended steps. This work provides a platform for future trials, training, and implementation of NEL.

Keywords: Neuro-endoscopic lavage, Post-haemorrhagic ventricular dilatation, Post-haemorrhagic hydrocephalus, Delphi consensus, Neurodevelopmental outcome

PF-047

Neurotrauma/Critical Care

Impairment in neurotransmitter balance after acute mild traumatic brain injury

Andrei Manzhurtsev¹, Maxim Ublinskiy², Tolib Akhadov³, Natalia Semenova¹

¹Clinical and Research Institute of Emergency Pediatric Surgery and Trauma

²Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences

³Moscow State University

BACKGROUND AND AIM: The mechanisms underlying functional disorders in the central nervous system (CNS) caused by traumatic brain injury (TBI) require intensive research. The balance between major neurotransmitters (excitatory – glutamate, and inhibitory – ?-aminobutyric acid, GABA), is crucial for the normal functioning of CNS. However, GABA concentrations vary in different cerebral zones [1] responsible for different cerebral tasks. In this study, [GABA] is measured in the posterior cingulate cortex (PCC) of children with acute mTBI.

METHOD: Seventeen patients with acute mTBI (12–70 h since the injury, aged 15.7 ± 1.9) and fifteen healthy age- and sex-matched subjects participated in the study. MRI scanner Philips Achieva dStream 3.0 T was used. Standard MRI protocol for TBI patients was applied, no pathological lesions in brain tissue of any subject were found. Magnetic resonance spectroscopy (MEGA-PRESS pulse sequence [2]) was applied in order to obtain GABA signal not contaminated by macromlecules. Spectroscopy voxel location is demonstrated on Fig. 1. The intensities of GABA, glutamate + glutamine, creatine and water signals were calculated in Gannet program [3]. Absolute concentrations of GABA and Glx were calculated. Statistical analysis was performed in STATISTICA 12. The Mann–Whitney criterion was used to reveal the significance of between-group differences.

RESULTS: The values of [GABA] in PCC in mTBI are statistically significantly increased by 22%, p = 0.0077. No changes in Glx were found.

CONCLUSIONS: The result obtained in current work is in agreement with the result of our previous study, where GABA was found increased (p < 0.005) in the anterior cingulate cortex of children with mTBI when comparing to healthy controls [4]. This indicates to a necessity of further data collecting in order to be ensured in the presence of [GABA] alterations in various cerebral loci. This would help to identify the causes of an inhibition/excitation imbalance and to predict possible dysfunctions of the CNS following mild TBI.

Keywords: mTBI, GABA, MRS

PF-048

Neurotrauma/Critical Care

Technical adaptations and applications of microdialysis in paediatric neurocritical care

Anthony Figaji¹, Rentia Lourens¹, Jill Combrinck¹, Phophi Tshavhungwe¹, Lindizwe Dlamini¹, Shamiel Salie², Nqobile Thango¹, Nico Enslin¹, Ursula Rohlwink¹

¹Division of Neurosurgery and Neuroscience Institute, University of Cape Town

²Division of Paediatric Critical Care, University of cape Town

BACKGROUND AND AIM: Microdialysis (MD) is an advanced tool to monitor targeted metabolites in brain extracellular fluid (ECF), but little is known about its application in children. Current limitations of the conventional method (tissue-MD) include compartmentalization and the poor quantification of true concentrations (relative recovery). We report our experience using MD with high molecular weight cut-off membranes to examine macromolecules as well as our recent adaptation to enable continuous CSF analysis to address tissue-MD limitations.

METHOD: We conducted a prospective study of children with severe traumatic brain injury (TBI) and meningitis (bacterial and tuberculous [TB]). Standard MD biochemistry was performed hourly at the bedside; remnant MD fluid was frozen for offline analysis. 100 kDa MD catheters were used for tissue MD. A novel adapted method of CSF MD monitoring was developed with CSF drainage flow-controlled through a Liquorguard pump (CSF-MD) using 20 kDa and 100 kDa catheters. We performed in vitro experiments to determine the influence of multiple variables (eg, flow rate and pressure) on sample analysis.

RESULTS: We performed MD monitoring in 82 children: 72 with conventional tissue-MD (61 TBI, 11 meningitis); 10 with the new CSF-MD method (8 meningitis; 2 TBI). Of the standard biochemistry, the lactate/pyruvate ratio was most useful: increases correlated with compromised brain tissue oxygenation. Offline analysis of proteomics and inflammatory mediators was successful. The limitations of tissue-MD were addressed by the new CSF-MD method. This enabled, for the first time, high quality data of bound and unbound drug in hourly sampling. We analysed antibiotics (anti-TB drugs, Ceftriaxone, Cefazolin), analgesics and sedatives (morphine, midazolam, ketamine) and anti-convulsants (levetiracetam).

CONCLUSIONS: This is the first large scale MD study in children, demonstrating examination of metabolites, proteins, inflammatory mediators, and drug penetration. Our CSF-MD adaptation has enabled, for the first time, high frequency quantitative drug recovery in the CSF, both for research and potentially individualized management.

Keywords: Microdialysis, Neurocritical care, Neurotrauma, Meningitis, Pharmacokinetics, Microdialysis

PF-049

Neurotrauma/Critical Care

Analysis of infantile subdural hematoma based on a nationwide multicenter retrospective study in Japan

Young Soo Park¹, Nobuyuki Akutsu², Ayumi Narisawa³, Atsuko Harada⁴, Mihoko Kato⁵, Masahiro Nonaka⁶

¹Department of Neurosurgery and Children’s Medical Center, Nara Medical University, Nara, Japan

²Department of Neurosurgery, Hyogo Prefectural Kobe Children’s Hospital, Hyogo, Japan

³Department of Neurosurgery, Sendai City Hospital, Miyagi, Japan

⁴Department of Pediatric Neurosurgery, Takatsuki General Hospital, Osaka, Japan

⁵Department of Neurosurgery, Aichi Children's Health and Medical Center, Aichi, Japan

⁶Department of Neurosurgery, Kansai Medical University, Osaka, Japan

BACKGROUND AND AIM: It is an undeniable truth that subdural hematoma (SDH) in infants is caused by shaken baby syndrome (SBS), and the possibility of abusive head trauma (AHT) should be considered. However, it should not be ignored that SDH is also caused by accidents inside the house. The recent confusion in AHT's judgment is derived from the fact that the actual occurrence of SDH due to accidents has not been fully verified. The purpose of this study was to investigate SDH by an all-cases survey.

METHOD: This multicenter, retrospective study reviewed the clinical records of children younger than 4 years with any abnormal findings on CT between 2014 and 2020. The accidental group was judged by the child protection team and/or the child guidance center. Multivariate analysis was conducted to identify which factors increase the risk of nonaccidental injury.

RESULTS: Of the 452 patients, 158 were diagnosed with SDH. A total of 51 patients were classified into the nonaccidental group, and 107 patients were classified into the accidental group. The age of patients with SDH showed a bimodal pattern. The mean age of the accidental group was significantly older than that in the nonaccidental group (10.2 months vs 5.9 months). The details of the injury mechanism were self-inflicted fall in 30 cases and falling from a bed or sofa in 19 cases, which is consistent with Nakamura's type 1 hematoma well known in Japan. Multivariate analysis showed patients under 5 months old, retinal hemorrhage, and seizure were significant risk factors for　nonaccidental injury. Further unexplained convulsion was significantly associated with increased odds of nonaccidental injury. Of the 23 cases with so-called trias, 11 were actually accident cases.

CONCLUSIONS: Infantile SDH was frequently observed in accidental injuries. SDH is a powerful discovery for detecting AHT, but careful consideration and comprehensive understanding should be required to determine AHT.

Keywords: Infantile subdural hematoma, Abusive head trauma, Nakamura Type 1 Intracranial Hemorrhage, Nationwide multicenter retrospective study

PF-050

Neurotrauma/Critical Care

Non accidental head and body injury patterns in Costa Rica during Covid-19 lockdown and post-lockdown periods

Adrian Caceres¹, Esteban Granados Fonseca², Andrea Monge Sanabria³

¹Neurosurgery department, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

²Social Work department, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

³Trauma unit, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

BACKGROUND AND AIM: Diverse social and family dynamics were observed during the compulsory lock down period due to the Covid 19 epidemic.

Our purpose was to analyze the patterns of accidental and non accidental head and body injuries and to correlate the documented cases of non accidental severe head injury before and after the lockdown period in order to establish if these exceptional circumstances influenced the occurrence of inflicted severe head injury in infants.

METHOD: We performed a retrospective analysis of all children referred with trauma related injuries to the sole institution for pediatric neurosurgical care in Costa Rica. We reviewed all admissions related to trauma at the ED and did a retrospective analysis of age, trauma related injuries, cases suspected to be non accidental and the overall impact of these lesions during the 2 strict lockdown periods in Costa Rica.

RESULTS: there was a significant decrease on the number of trauma related cases referred to our trauma unit. A 57% and 48% decrease of total cases was observed during the first and second 3 month lockdown periods of 2020. A significant decrease in the number and severity was observed in MVA and a increase in household burns, dog bites and falls. There was a total 44% decrease of cases of non accidental injuries. There were only 4 children who died due to accidental trauma in 2020 as opposed to 10 in 2019. None of the patients who died during 2020 were related to non accidental severe head injury.

CONCLUSIONS: Contrary to the suspected increase in domestic violence during the 2020 lockdown a family protective environment was observed in households probably by preventing the aggressors to be left alone with infants and therefore preventing severe non accidental head injury. Most injuries observed were related to household conditions (burns, dog bites, falls).

Keywords: Non accidental head injury, Covid-19 lockdown, Domestic violence, Trauma, Children

PF-051

Epilepsy

Long-term outcome of surgery in children with drug resistant epilepsy and focal cortical dysplasia

Manas Panigrahi¹, Sitajayalakshmi Sattaluri², Sailiaja Mudumba³

¹Dept of Neurosurgery, KIMS

²Dept of Neurology, KIMS

³Dept of Pathology, KIMS

BACKGROUND AND AIM: To evaluate factors affecting outcome in children with drug resistant epilepsy and focal cortical dysplasia (FCD) who underwent surgery.

METHOD: We analyzed data of 112 consecutive children operated at a tertiary referral centre for drug resistant epilepsy and a diagnosis of FCD on histopathology between January2005 and December 2015. The inclusion criteria were 1) isolated type I and/or type II FCD within the surgical specimen 2) at least five years post-surgery follow-up.

RESULTS: The average age at onset of epilepsy was 4.56 ± 3.88 (0 – 18) years with mean duration of epilepsy of 6.50 ± 5.02 (0.3– 18) years. The average age at surgery was 10.27 ± 5.14 (2 – 18)years. Delayed development was observed in 39 (34.8%), while 56 (50.0%) had below average intelligence. Associated psychiatric disorder and /or behavioural problems were diagnosed in 67 (59.8%) patients. Inter-ictal EEG showed focal/regional epileptiform discharges in 55 (49.1%). Seizure semiology was lateralizing in 77 (68.8%) while 52 (46.4%) had regional ictal EEG onset. MRI showed clear cut FCD in 96 (85.7%). At the latest follow-up 73 (65.2%) patients had a favourable Engels outcome. Onset of seizures below two years of (30.1 vs 53.8%; p = 0.024,) multiple types of seizures at presentation (21.9% vs 46.2%; p = 0.010), developmental delay (23.3% vs 56.4%; p = 0.001), generalized seizure semiology (54.8% vs 79.5%; p = 0.013) and acute post-operative seizures (19.4% vs 48.7%; p = 0.002), were associated with unfavourable outcome. Complete resection of the FCD (91.8% vs 46.2%; p < 0.001), type II FCD (51.4% vs 21.2%; p = 0.027), lateralizing semiology (75.3% vs 56.4%; p = 0.054) were associated with favourable outcome. The predictor for favourable outcome was complete resection.

CONCLUSIONS: Favorable outcome after surgery for DRE and FCD in children was seen in 65% and complete resection was the predictor of favourable outcome.

Keywords: Focal cortical dysplasia, Epilepsy surgery

PF-052

Epilepsy

The MAST Trial: Prospective evaluation of a machine learning algorithm for the planning of SEEG trajectories

Aswin Chari¹, Sophie Adler⁵, Konrad Wagstyl⁵, Kiran Seunarine⁵, Zubair Tahir¹, Friederike Moeller³, Rachel Thornton³, Stewart Boyd³, Krishna Das³, Gerald Cooray³, Felice D'arco⁴, Torsten Baldeweg⁵, Christin Eltze², Helen Cross², Martin Tisdall¹, Ido Ben Zvi¹

¹Department of Neurosurgery, Great Ormond Street Hospital

²Department of Neurology, Great Ormond Street Hospital

³Department of Neurophysiology, Great Ormond Street Hospital

⁴Department of Neuroradiology, Great Ormond Street Hospital

⁵Institute of Child Health, University College London

BACKGROUND AND AIM: Despite a plethora of machine learning algorithms that have been developed in the field of epilepsy, few have undergone prospective clinical evaluation with a view to being integrated into routine clinical practice. Here, we report results of a prospective evaluation a lesion detection algorithm designed to detect focal cortical dysplasia (FCD) in children undergoing stereoelectroencephalography (SEEG) at a single centre.

METHOD: This was a prospective single arm interventional (IDEAL phase 1/2a) study of 20 patients. Children undergoing SEEG were enrolled. Following routine SEEG planning, T1 and Flair MRI scans were run through the MELD lesion detection algorithm to identify putative lesion clusters, which were merged with the planned electrode trajectories. If the top 3 MELD-identified lesion clusters were not already sampled, up to 3 additional SEEG electrodes were added. The primary outcome measure was the proportion of patients that had additional electrode contacts in the SEEG-defined seizure onset zone. Secondary outcomes included safety and efficacy end points.

RESULTS: Twenty patients (median age 12, range 4–18) were enrolled over 2 years, one of whom did not end up undergoing SEEG implantation. Additional electrode contacts were part of the SOZ in 1/19 (5.3%) whilst 2/19 (10.5%) had lesions clusters that were part of the SOZ but already implanted. A total of 63 lesion clusters were identified (range 0–11), of which 23 fulfilled criteria for implantation. A total of 16 additional electrodes were implanted in 9 patients and there were no adverse events from the additional electrodes implanted.

CONCLUSIONS: We demonstrate early-stage prospective clinical validation of a machine learning lesion detection algorithm in aiding the identification of the seizure onset zone in children undergoing SEEG. Further multi-centre validation will build the rationale for incorporating such technology into routine clinical use.

Keywords: Epilepsy, Seeg, Machine learning

PF-054

Epilepsy

Quality of life of children with surgically treated epilepsy-the patient’s perspective

Ido Ben Zvi, Aswin Chari, Martin Tisdall

Department of Neurosurgery, Great Ormond Hospital for Children

BACKGROUND AND AIM: Clinical trials and studies in epilepsy surgery commonly use the seizure outcome (Engel or ILAE Classification) as the primary outcome measure, with the focus being on the proportion of patients achieving seizure freedom. However, little data exists as to what outcomes are important to patients and their carers. We sought to ascertain the most important outcomes for patients and their carers.

METHOD: An international online anonymous survey was conducted through patient advocacy groups. The survey consisted of 18 multiple choice questions. In addition to demographic questions about the patient and the management of their epilepsy, the survey asked what the most important outcomes were across multiple domains including seizure-related, cognition and developmental, quality of life and other long-term outcomes.

RESULTS: 204 patients or parents/carers responded to the survey. 61% were children or their carers. 72% report focal seizures (30% of them have generalized seizures as well). 53.4% currently have more than one seizure a month (23.5% daily). 37.2% of patients had undergone surgery. Half of them reported seizure freedom, and 90% reported postoperative improvement. When asked what outcome measure was most important, 44.6% responded being seizure free and 26% desired improvement in quality of life. When asked about the timing of potential surgical treatment, 64.7% would consider having surgery soon after the diagnosis of epilepsy; this percentage was higher among operated patients (72%), but without statistical significance (p = 0.077).

CONCLUSIONS: More than third of our cohort had an operation, with half reporting seizure freedom. Across this large sample, the most important outcome measure is being seizure-free, reinforcing focus on seizure freedom in clinical trials. The second most important outcome measure was quality of life, emphasizing the need to measure these outcomes in clinical studies of epilepsy and epilepsy surgery. Many would consider early surgery and the risks and benefits of this warrant further study.

Keywords: Epilepsy surgery, Quality of life, Seizure outcome, Patient perspective

PF-055

Epilepsy

Detection of focal cortical dysplasia in drug-resistant epilepsy using Raman Spectroscopy

Trang Tran¹, Frederic Dallaire², Romain Cayrol³, Joshua Sonnen⁴, Frederic Leblond¹, Roy Dudley⁴

¹Research Institute of the McGill University Health Centre; Polytechnique Montréal; Centre Hospitalier Universitaire de Montréal (CRHUM)

²Département Imagerie Optique, Polytechnique Montréal

³Department of Pathology, Centre Hospitalier Universitaire de Montréal (CHUM)

⁴Department of Neurology and Neurosurgery, McGill University Health Center (MUHC)

BACKGROUND AND AIM: Focal cortical dysplasias (FCD), characterized by abnormal cortical architecture, are the most common cause of drug-resistant focal epilepsy in the pediatric population. Children with this disorder can have tens to hundreds of seizures per day, and only surgery can remove FCD lesions to cure focal epilepsy, but surgical success depends on the ability to resect the lesion completely while minimizing damage to perilesional normal tissues. However, these lesions and/or their borders are usually not well seen on MRI, making them very difficult to remove completely. Thus, new imaging techniques for detecting FCD margins during surgery are needed to improve surgical results. Raman spectroscopy (RS) is a nondestructive, label-free optical method, that allows the characterization of the tissue composition. The goal of this ex-vivo and on-going in-vivo study is to use Raman spectroscopy to discriminate between normal and dysplastic brain tissue.

METHOD: 85 stained sections of biopsy specimens from 30 patients with focal epilepsy were acquired ex-vivo, 5 in-vivo specimens were probed by the neurosurgeon in areas believed to contain FCD based on the presurgical evaluation data and pre-operative plan, and all the specimens were assessed by a pediatric neuropathologist. In the ex-vivo, Raman map points were recorded from targeted abnormal regions with structures characterizing FCD: dysmorphic neurons, balloon cells and cortical dyslamination using a Raman microscope.

RESULTS: With more than 2000 spectra acquired, significant spectral differences were observed between the dysplastic tissue regions and normal regions in the cortex. Indeed, FCD tissues exhibited significantly increased spectral at the peaks of proteins (DNA, RNA and phenylalanine) and interestingly, lower in lipids. We then trained a machine learning model capable of detecting FCD tissues with a 96% accuracy, 100% sensitivity and 95% specificity.

CONCLUSIONS: By accurately detecting dysplastic tissues, quantitative RS holds the potential for improving the accuracy of brain epilepsy surgery in real-time.

Keywords: Epilepsy, Focal cortical dysplasia, Raman spectroscopy, Neurosurgery

PF-056

Functional

Predicting success in selective dorsal rhizotomy (SDR): past, present and future

Benedetta Pettorini¹, Conor S. Gillespie², Chris Sneade¹, Benjamin J. Hall¹

¹Department of Neurosurgery, Alder Hey Children's Hospital NHS Foundation Trust, Liverpool, UK

²The University of Liverpool

BACKGROUND AND AIM: Patient selection for selective dorsal rhizotomy (SDR) is complex, depends on a number of variables and has little international consensus: resulting in significant heterogeneity. We reviewed previous attempts at predicting SDR outcomes and present our attempt at designing a predictive scoring tool to aid in patient selection.

METHOD: All SDR patients at a UK paediatric neurosurgical centre operated between 2014–2020, with minimum 12-months follow-up, were included. ‘Success’ was defined as: at least one ‘patient reported’ improvement (pain reduction, quality of life score) plus one ‘patient observable improvement’ (clinically significant increase in GMFM, PEDI, MAS, or 6MWT scores). Univariable logistic regression analysis was performed to determine factors associated with SDR success, before incorporation into a multivariable regression model if p < 0.01. Literature review was performed utilising search terms: ‘predicting’, ‘outcome’, ‘SDR’ and ‘cerebral palsy’.

RESULTS: 73 children were included (median age 6.2 years, IQR 4.75–8.00). 61.6% female (n = 45). SDR success was observed in 58.9% of children at 6 months (n = 43/73) and in 67.1% of children at 12 months (n = 49/73). The only factor associated with success on univariable analysis was ‘lack of dystonia’ (Odds ratio [OR] 5.06, 95% confidence interval [CI] 0.85–30.23, p = 0.076). Non-significant (p > 0.05) factors on univariable analysis were: age (OR 1.02, 95% CI 0.86–1.20), Female sex (OR 1.82, 95% CI 0.64–5.19), Baseline GMFCS (OR 0.69, 95% CI 0.37–1.27), Baseline GMFM (OR 1.04, 95% CI 0.99–1.10), and Pain score (OR 1.03, 95% CI 0.86–1.19). Literature review identified 10 articles identifying preoperative factors predictive of outcome, though no clinically applicable scoring system currently exists.

CONCLUSIONS: ‘Success’ following SDR remains challenging to define and predict. Few preoperative factors accurately predict success; preventing development of any clinically useful predictive tool. Consensus meetings and high-quality follow-up data are required to better define ‘success’, identify associated factors and allow more rigorous statistical analysis to aid in future patient selection.

Keywords: Selective dorsal rhizotomy, Success, Predict, Outcomes

PF-057

Functional

Ultrasound Level Check in Selective Dorsal Rhizotomy – Experience in 152 cases

Chloé Louise Gelder¹, Ieva Sataite², Rebecca Sarah Chave Cox¹, John Robert Goodden¹

¹Regional Neurosciences Centre, Department of Neurosurgery, Leeds Children's Hospital, Leeds, United Kingdom

²Department of Neurosurgery, Royal Hospital for Children and Young People, Edinburgh, United Kingdom

BACKGROUND AND AIM: Selective Dorsal Rhizotomy (SDR) surgery typically requires a level check for L1, to identify the conus location using on-table x-ray, pre-operative marking and/or ultrasound. We present a case series of 152 SDR operations undertaken using pre-operative (percutaneous) and intra-operative ultrasound as the main modality for the level check.

METHOD: The Leeds Children’s Hospital prospective SDR database was used to identify patients. All operation notes were reviewed, recording the method used for level check.

RESULTS: In total 152 SDR patients have had SDR, mean age 6.48 years (range 2.63–19.06); 76 GMFCS II, 76 GMFCS III; M:F 95:57. Pre-operative level check was performed with ultrasound alone in 141 patients; 11 had combined x-ray & ultrasound level check. The 11 patients who had combined x-ray & ultrasound level checks, were the first patients having SDR in our centre. This allowed the surgeon to assess accuracy and establish the feasibility of percutaneous ultrasound at the start of surgery instead of x-ray. For the subsequent 141 patients, ultrasound alone was sufficient for both pre-operative (percutaneous) and intra-operative level-check, even for those aged > 10-years. During the course of surgery, once the wound was opened, all 152 patients had an intra-operative ultrasound level check to confirm the level of the conus before opening the dura. There were no instances of wrong-level surgery with this technique.

CONCLUSIONS: In our experience, following a short period of learning, ultrasound has proven to be safe and effective for perioperative identification of the conus level for SDR surgery in all ages. This has the advantage of avoiding a radiation dose, saving x-ray cost and improving theatre workflow efficiency.

Keywords: Selective dorsal rhizotomy, Ultrasonography, Intra-operative level check, Cerebral palsy

PF-058

Dysraphism

Characterizing syringomyelia and its clinical significance in 140 patients with lipomyelomeningocele

Ananth P Abraham¹, Tarang K Vora¹, Bernice T Selvi², Vedantam Rajshekhar¹

¹Department of Neurological Sciences, Christian Medical College, Vellore, India

²Department of Radiology, Christian Medical College, Vellore, India

BACKGROUND AND AIM: The aim of this study was to characterize syringomyelia in patients with lipomyelomeningocele (LMMC) and determine its association with their neurological deficits.

METHOD: A single-centre, observational study included a retrospective chart review of children with LMMC diagnosed between 2007 and 2020. Those who had synchronous dysraphic conditions such as split-cord malformations or dermoid cysts were excluded. Syringomyelia on magnetic resonance imaging (MRI) was classified into 3 groups – true syrinx, early syrinx and pre-syrinx based on clearly defined criteria. Correlation of neurological deficits (at birth, new onset and progressive) with the presence and type of syrinx was studied.

RESULTS: A total of 140 patients met the inclusion criteria. The median age of the patients was 2.5 (IQR 1.3–9) years. Neurological deficits were present at birth in 75 (53.6%) patients while 67 (47.9%) had new-onset deficits or progression of their birth deficits. The most common type of spinal lipoma was the transitional type (75.7%). Thirty nine (27.8%) patients had syrinx (37 had true syrinx, 2 had early syrinx) and 25 (17.9%) patients had pre-syrinx. There was no significant correlation between the presence of a syrinx (true and early) or pre-syrinx and patients’ neurological deficits. However, patients with a syrinx that was not adjacent to the lipoma (≥ 1 vertebral level away) had a higher incidence of deficits at birth (p = 0.04) while those with a syrinx spanning ≥ 5 vertebral levels had a higher incidence of progressive neurological deficits (p = 0.04). Six of 8 (75%) patients in whom serial MRI showed progression of syrinx had clinical worsening.

CONCLUSIONS: Syrinx location with respect to the spinal lipoma, syrinx length and progressive syringomyelia may have clinical significance in patients with LMMC.

Keywords: Syringomyelia, Syrinx, Characterization, Lipomyelomeningocele, Dysraphism

PF-059

Spine

Pediatric congenital atlantoaxial dislocation: Our experience, challenges and solutions

Karthigeyan Madhivanan, Pravin Salunke, Sushanta Sahoo, Narasimhaiah Sunil

Department of Neurosurgery, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India

BACKGROUND AND AIM: The management aspects of pediatric congenital atlantoaxial dislocation (CAAD) differ from that of the adults. Softer bones, highly deformed joints, and fusion of multiple vertebral levels with potential for spinal growth impairment in younger age are a few unique challenges pertaining to this age group. We describe our experience and the related challenges along with solutions, following multiplanar realignment and short-segment C1-C2 fusion in children with CAAD.

METHOD: A total of 56 pediatric patients with congenital AAD underwent C1-C2 posterior reduction and fixation. The oblique C1-C2 joints were drilled, and remodeled to achieve multiplanar realignment. The baseline clinico-radiological data were compared with that of the follow up.

RESULTS: The series included 35 cases with irreducible and 21 cases with reducible AAD; the former had a higher incidence of bony anomalies, and the joints were more oblique and deformed. Nine patients had lateral angular dislocation, 3 had C1-C2 spondyloptosis and 5 had significant vertical dislocation. The C1-C2 joint drilling and manipulation was feasible in all patients. The operative techniques were modified to achieve an optimal bony purchase secondary to the drilling of relatively small bones and also avoid screw pull out during intraoperative manipulation. Despite some challenges in few initial cases, realignment could be achieved in all. At follow up, there was a significant improvement in mJOA score in 95.8% of cases, with 28 patients being independent.

CONCLUSIONS: Children show relatively high oblique C1-C2 joints and therefore a frequent occurrence of spondyloptosis, severe vertical dislocation and lateral tilt. Despite the soft and small pediatric bones, a multiplanar realignment could be achieved by C1-C2 joint drilling and manipulation. The short segment C1-C2 fusion offers satisfactory clinical and imaging outcome in pediatric CAAD.

Keywords: Craniovertebral junction, Atlantoaxial, Pediatric spine, C1-C2, Basilar invagination, Multiplanar

PF-060

Spine

Complications and outcomes of posterior fossa decompression with duraplasty versus without duraplasty for pediatric patients with Chiari I malformation and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium

Syed Hassan Abbas Akbari¹, Alexander Yahanda², David Delmar Limbrick², The Park Reeves Syringomyelia Research Consortium Contributors³

¹Department of Neurosurgery, Johns Hopkins University School of Medicine, Johns Hopkins All Children's Hospital, St. Petersburg, FL, United States

²Department of Neurosurgery, Washington University School of Medicine in St. Louis, St. Louis, MO, United States

³The Park-Reeves Syringomyelia Research Consortium Contributors

BACKGROUND AND AIM: Chiari I malformation with syringomyelia (CM1-SM) is commonly treated with either a posterior fossa decompression with (PFDD) or without (PFD) duraplasty. The aim of this study was to determine differences in complications and outcomes between PFDD and PFD for pediatric CM1-SM.

METHOD: Surgically treated CM1-SM patients with on-year follow-up data were identified using the Park-Reeves Syringomyelia Research Consortium database. Preoperative, treatment, and postoperative characteristics were compared.

RESULTS: 692 patients met inclusion criteria. PFD was performed in 117 and PFDD in 575 patients. The mean age at surgery was 9.86 years and follow-up time was 2.73 years. There were no differences in presenting signs or symptoms between groups, though preop syrinx size was smaller in the PFD group. The PFD group had shorter OR time (p < 0.0001) and hospital stays (p = 0.0001), and lower blood loss (p = 0.04). There were 4 intraoperative complications, all within the PFDD group (0.7%, p = 1.00). PFDD patients had a higher 6-month complication rate (24.3% versus 13.7%, p = 0.01). There were no differences between groups for postoperative complications beyond 6 months (p = 0.33). PFD patients were more likely to require revision surgery (17.9% versus 8.5%, p = 0.004). PFDD showed greater improvements in headaches (89.6% versus 80.8%, p = 0.04) and back pain (88.3% versus 59.1%, p = 0.01). There were no group differences for improvement in neurological exam findings. PFDD showed greater reduction in AP syrinx size (43.7% versus 26.9%, p = 0.0001) and syrinx length (18.9% versus 5.6%, p = 0.04) compared to PFD. Among PFDD patients, allograft was associated with higher rates of pseudomeningocele (p = 0.041) and chemical meningitis (p = 0.002) compared to autograft.

CONCLUSIONS: PFD is associated with reduced operative time and blood loss, shorter hospital stays, and fewer postoperative complications. However, PFDD was associated with better symptom improvement, reduction in syrinx size, and lower revision rates. The two surgeries have low intraoperative complication rates and comparable complication rates beyond 6 months.

Keywords: Chiari I malformation, Posterior fossa decompression, Duraplasty, Complications, Revision

PF-061

Global Pediatric Neurosurgery

Comparison of long-term survival of pediatric patients with drug-resistant epilepsy: continued medical therapy, vagus nerve stimulation, and cranial epilepsy surgery

Lu Zhang¹, Matt Hall², Sandi Karen Lam¹

¹1Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA &Division of Pediatric Neurosurgery, Ann & Robert H Lurie Children’s Hospital of Chicago, Chicago, IL, USA

²Data and Biostatistics, Children's Hospital Association, Lenexa, KS, USA

BACKGROUND AND AIM: The mortality of pediatric patients with drug-resistant epilepsy (DRE) is higher than the general population and adult patients. A better understanding of the treatment effect on mortality is needed for healthcare decision making. This study compared the long-term survival rate associated with different types of therapy in pediatric patients with DRE.

METHOD: Patients aged 0–17 years and diagnosed with DRE between January 1, 2004 and December 31, 2020 were identified from the Pediatric Health Information System Database. Patients treated with anti-seizure medications (ASMs) only or ASMs plus vagus nerve stimulation (VNS) or ASMs plus cranial epilepsy surgery were included in the study and were followed until the date of their last clinical encounter, in-hospital death, or December 31, 2020. Kaplan–Meier and log-rank test were used to estimate and test the difference in the unconditional probability of survival. Cox proportional hazards model was performed to compare time to death in the follow-up period.

RESULTS: This study included 10,240 patients treated with ASMs only, 5,019 patients treated with VNS, and 3,033 patients treated with cranial epilepsy surgery. The unconditional probability of surviving beyond 10 years were 89.93% for medical therapy cohort (95% CI, 88.56% to 91.30%), 93.38% for VNS cohort (95% CI, 91.81% to 94.95%), and 98.29% for cranial surgery cohort (95% CI, 97.31% to 99.27%). The difference in the estimates of survival probabilities was statistically significant (p < 0.001). Compared with patients in the medical therapy cohort, the risks of overall death were reduced by 33% (HR = 0.660; 95% CI, 0.506 to 0.863) and 83% (HR = 0.168; 95% CI, 0.106 to 0.207) for patients in the VNS cohort and the cranial epilepsy surgery cohort, respectively.

CONCLUSIONS: Our findings suggest survival benefit with surgical treatments for DRE and point to the need for increased and more timely evaluations and referrals to comprehensive epilepsy centers where surgical treatments are available.

Keywords: Pediatric, Drug-resistant epilepsy, Survival, Anti-seizure medication, Vagus nerve stimulation, Epilepsy surgery

PF-062

Hydrocephalus

Genetically-determined alterations in inflammation and infection-associated genes cause hydrocephalus in patients of African Ancestry

Andrew T Hale¹, Steven J Schiff², Eric R Gamazon³

¹Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA

²Centers for Neural Engineering and Infectious Disease Dynamics, Departments of Neurosurgery, Engineering Science and Mechanics, and Physics, Penn State University. University Park, PA, USA

³Division of Genetic Medicine, Vanderbilt University Medical Center, Nashville, TN, USA

BACKGROUND AND AIM: The genetic mechanisms underlying hydrocephalus risk and pathogenesis are complex. Our group recently completed a comprehensive human genetic and functional genomics study of pediatrc hydrocephalus in patients of European ancestry (Hale et al., ‘Multi-omic analysis elucidates the genetic basis of hydrocephalus.’ Cell Reports, 2021), identifying genes involved in regulation of chromatin structure underlying hydrocephalus risk. However, the disease burden of hydrocephalus is amongst the highest in the world in Sub-Saharan Africa. Here we apply human genetics and functional genomics approaches to delineate the genetic basis of hydrocephalus in patients of African ancestry.

METHOD: We perform a transcriptome-wide association study (TWAS) in pediatric patients of African ancestry with hydrocephalus across 3,388 individuals (146 cases and 3,242 controls). Gene set enrichment analysis (GSEA) was performed to identify genetically-determined pathways conferring hydrocephalus risk.

RESULTS: After multiple-testing correction (false discovery rate < 0.05) across all genes tested, we identify decreased expression of TMEM208 as an outlier. TMEM208 met the highly-stringent Bonferroni threshold for statistical-significance based on the total number of genes tested (OR = 2.07, p < 5.22 × 10–8) indicating that TMEM208 is a transcriptome-wide predictor of hydrocephalus. GSEA of all nominally-associated genes (p < 0.05) revealed a marked association with genes regulating inflammatory and infection-related processes.

CONCLUSIONS: We perform the first systematic genetic study of hydrocephalus in patients of African ancestry. Whereas our previous study (Hale et al. Cell Reports, 2021) demonstrated that the genetic underpinnings of hydrocephalus in Europeans are largely driven by alterations in DNA structure, here we identify perturbations in inflammation and infection-associated genes underlying hydrocephalus in patients of African descent. Co-evolution of humans and pathogen-imposed selection pressures have differentially shaped the genetic etiology of hydrocephalus across ancestral populations.

Keywords: Hydrocephalus, Human genetics, Functional genomics, African

PF-063

Moya-Moya disease

Surgical Revascularization Decreases Stroke and TIA Risk in Children with Sickle Cell Disease and Moyamoya Syndrome: Results of the Stroke in Sickle Cell Revascularization Surgery Study (SiSCRS)

Philipp Aldana¹, Ricardo Hanel², Joseph Piatt³, Sabrina Han⁴, Corinna Schultz³, Manisha Bansal³

¹Wolfson Children's Hospital/University of Florida Jacksonville

²Lyerly Neurosurgery, Baptist Neuroscience Institute

³Nemours Children's Health

⁴University of Florida College of Medicine

BACKGROUND AND AIM: Recent studies have suggested that surgical revascularization may be a safe and effective therapy to reduce risk of cerebrovascular complications in patients with sickle cell disease and moyamoya syndrome (SCD-MMS). These studies have been limited by small sample size and lack of a control group for comparison.

AIM: To investigate whether revascularization surgery reduces the risk of cerebrovascular events (CVEs) in comparison to conservative management alone in a retrospective cohort of children with SCD-MMS.

METHOD: A retrospective review of data from 15 major U.S. pediatric neurosurgery centers of SCD-MMS patients (< 18 y.o.) was performed. Detailed information on sickle cell disease, stroke and surgical histories were extracted. The incidence of CVEs (stroke and TIAs) between patients treated with surgical revascularization was compared to those with conservative management alone. Multivariate regression models were generated and logistic regression analyses were performed.

RESULTS: A total of 141 patients with SCD-MMS were studied. 78 (55.3%) were treated with conservative management and revascularization surgery (Surgery group) and 63 (44.7%) were treated with conservative management alone (Conservative group). Patients in the Surgery group had reduced odds of developing a CVE over the duration of their risk period (odds ratio = 0.27, 95% CI: 0.08–0.94, P = 0.040). Furthermore, when comparing patients in the Surgery group during their pre-surgical periods and post-surgical periods, patients had markedly reduced odds of developing a CVE after surgery (odds ratio = 0.22, 95% CI = 0.08–0.58, P = 0.002). Postoperatively, 3 patients had CVEs and 4 had non CVE complications.

CONCLUSIONS: Our retrospective study provides strong evidence that revascularization surgery can be performed safely and reduce risk of CVEs in patients with SCD-MM. This is the largest study of its kind to date. A prospective study will be needed to validate our findings.

Keywords: Sickle cell disease, Moyamoya syndrome, Stroke, Transient ischemic attack, Cerebrovascular events

PF-064

Global Pediatric Neurosurgery

Global Alliance for the Prevention of Spina Bifida (GAPSBIF); Organization, Evolution and Early Progress toward Global Folic Acid Fortification

Jeffrey P Blount¹, Gail Rosseau², Vijaya Kancherla³, Frederick A Boop⁴, Kemel Ghotme⁵, Adrian Caceres Chacon⁷, Marinus Koning¹², Anastasia Smith¹, Eylem Ocal⁶, Sylvia Roozen¹⁰, Jogi Patissipu¹³, Pedram Maleknia¹, Amanda Dorsey³, Nathan Shlobin⁸, Helena Pachon³, Yakob Ahmed³, Sylvia Roozen¹³, Walter Johnson¹⁵, Dan Peterson¹⁴, Ken Anselmi¹⁶, Martina Gonzalez¹⁷, Priyanka K Mathur⁸, Homero Martinez¹¹, Godfrey Oakley², Kee Park⁹

¹University of Alabama at Birmingham Department of Neurosurgery

²George Washington University Department of Neurosurgery

³Center for Spina Bifida Prevention, Rollins School of Public Health, Emory University

⁴St. Jude Children's Research Hospital

⁵Santa Fe Foundation of Bogota Colombia

⁶University of Arkansas Department of Neurosurgery

⁷National Hospital for Children, San Jose, Costa Rica

⁸Northwestern University Department of Neurosurgery

⁹Harvard Program in Global Surgery and Social Change

¹⁰International Federation for Prevention of Spina Bifida

¹¹Nutrition International

¹²ReachAnother Foundation

¹³University of Central Florida

¹⁴G4 Alliance

¹⁵Center for Global Surgery, Loma Linda University

¹⁶East Carolina University

¹⁷Kings College, London

BACKGROUND AND AIM: Despite three decades of class I evidence demonstrating safety and effectiveness of folic acid fortification to prevent Spina Bifida (SB) less than 25% of prevented SB is prevented. Over 300,000 new cases of SB occur annually world-wide and the majority are preventable. GAPSBIF is a global alliance of neurosurgeons, epidemiologists and other clinical and public health professionals dedicated to science-based advocacy to attain global folic acid fortification. This presentation summarizes current initiatives, progress and key goals.

METHOD: Five enabling objectives are being purused. First, a resolution based upon an ISPN resolution supporting global fortification was introduced at WHA in June 2022. A primary objective will be adaptation by World Health Assembly of the resolution recently proposed. Second, updated publications, webinars and special events are occurring to inform key policy makers. Third, salt is being evaluated for feasibility to deliver sufficient folic acid to women of childbearing age. Fourth, high-risk intervention (and after-care) is being pursued in regions of high endemic SB prevalence. Finally, key relationships and individual partnerships with lead countries (Colombia, Ecuador, Ethiopia, India and Turkey) and other clinical stake holders are being fostered.

RESULTS: In June 2022 Colombia sponsored a resolution at WHA supporting global fortification. At the same time a review paper by GAPSBIF members was published in Lancet-Global Health. Other monographs are in production. Passage of the WHA resolution will require robust advocacy of WHA member states. Active advocacy and fostering of health ministers continue in targeted partnership countries. Salt is being investigated in at least 3 clinical trials. Supplementation and multi-disciplinary after care programs are expanding in Ethiopia and models for after care are being implemented.

CONCLUSIONS: ISPN neurosurgeons are central to GAPSBIF and are making progress toward global fortification. Opportunities for involvement and further engagement will be detailed.

Keywords: Advocacy, Folic acid, Spina bifida, Prevention

Flash Presentation Abstracts

FL-001

Neuro-Oncology

Lumbar Fenestration to Temporize Hydrocephalus after Craniotomy for Posterior Fossa Tumors in Children

Alex Y Lu, Peter P Sun

University of California, San Francisco

BACKGROUND AND AIM: Pediatric patients with newly diagnosed posterior fossa tumors frequently present with hydrocephalus. Even after external ventricular drainage and craniotomy for tumor resection, hydrocephalus may persist in the postoperative period. Lumbar fenestration, a technique that creates a temporary lumbar pseudomeningocele, can be performed under local anesthesia and may act as a temporary pressure release valve. This study investigates whether lumbar fenestration can reduce the postoperative incidence of cerebrospinal fluid diversion after craniotomy for posterior fossa tumor resection in children.

METHOD: A retrospective review of pediatric patients (presenting age < 18 years) was conducted at the University of California, San Francisco and Children’s Hospital Oakland between January 1st, 2010 and January 1st, 2022. Inclusion criteria for this single surgeon series includes patients with newly diagnosed posterior fossa tumor with evidence of hydrocephalus at presentation that subsequently underwent craniotomy for tumor resection and external ventricular drain placement. Exclusion criteria included supratentorial lesions, insufficient medical records, pre-operative ventriculoperitoneal shunting, or first craniotomy at external facility.

RESULTS: After evaluation, 55 patients with newly diagnosed posterior fossa tumors were identified who underwent craniotomy for tumor resection. 43 patients (78.2%) had hydrocephalus at presentation. The diagnoses of these patients included medulloblastoma (53.3%), pilocytic astrocytoma (23.3%), ependymoma (13.3%), atypical teratoid rhabdoid tumor (6.7%), and ganglioglioma (3.3%). Of the 43 patients with hydrocephalus, 30 patients underwent lumbar thecal sac fenestration. 14 (46.7%) of these patients have not required CSF diversion at last follow-up. No patients had complication attributed lumbar thecal sac fenestration nor did any patient require a blood patch postoperatively.

CONCLUSIONS: Lumbar fenestration has a low complication profile and may be a promising technique to reduce the incidence of cerebrospinal fluid diversion after craniotomy for posterior fossa tumor resection in pediatric patients.

Keywords: Lumbar fenestration, Posterior fossa tumor, Hydrocephalus

FL-002

Neuro-Oncology

Role of extent of resection in Medulloblastoma in context of molecular subgrouping—a retrospective audit

Prakash Shetty, Ujwal Yeole, Rajesh Krishna, Vikas Singh, Aliasgar Moiyadi

Department of Neurosurgery, Tata Memorial Hospital, and Homi Bhabha National Institute, Mumbai, India

BACKGROUND AND AIM: Extent of resection, along with age and metastatic status are important factors for risk stratification for deciding treatment in medulloblastomas.This study aims to look at the role of extent of resection in medulloblastomas in the context of molecular subgrouping.

METHOD: It is a retrospective audit of medulloblastoma patients looking at the role of extent of resection(EOR) in terms of PFS(progression free survival) and OS(overall survival) for the entire cohort and molecular subgroups (WNT/SHH/Group3/Group 4).The extent of resection was defined as gross total (GTR), Near total (NTR < 1.5 cc residue) and subtotal resection (STR > 1.5 cc residue).

RESULTS: 437 patients data over 15 year period, with molecular subgrouping data of 296 patients was available.221 cases were selected after removing the patients lost to follow up. The gender and metastasis were different in each molecular subgroup(statistically significant), however treatment factors like EOR, adjuvant and radiation therapy were similar. The distribution for molecular subgroups were- (WNT-38, SHH-83, Group 3–34,Group 4–66) and the survival was best for WNT subgroup, followed by SHH and then group 4 and 3.

For the entire cohort (221),there was no statistical difference in the PFS and OS when considering the EOR. Taking the molecular group into consideration, in the WNT and SHH subgroup,PFS and OS were not influenced by EOR. In group 3, the PFS was tending towards significance, while the OS was influenced with EOR, with GTR doing better than STR(statistically significant).In group 4,OS was tending towards significance, by the EOR.

CONCLUSIONS: EOR in group 3 medulloblastoma influenced the overall survival in our cohort. Hence a safe maximal resection is advocated and results should be interpreted with the limitations of a retrospective audit.

Keywords: Medulloblastomas, Extent of resection, Molecular subgrouping

FL-003

Neuro-Oncology

The supraorbital eyebrow approach in pediatric neurosurgery—patient characteristics, clinical course and outcome

Ulrich Wilhelm Thomale¹, Aminaa Sanchin¹, Pablo Hernaiz Driever³, Anna Tietze⁴, Eckhardt Bertelmann²

¹Pediatric Neurosurgery, Charité Universitätsmedizin Berlin, Germany

²Department of Ophtalmology, Charité Universitätsmedizin Berlin, Germany. 

³Pediatric Hematology and Oncology, Charité Universitätsmedizin Berlin, Germany

⁴Neuroradiology, Charité Universitätsmedizin Berlin, Germany

BACKGROUND AND AIM: Supraorbital craniotomy via an eyebrow incision provides access to both orbital and intracranial pathologies in a minimally invasive technique with clinically and cosmetically favorable outcome. We describe the indication, surgical technique and clinical course using this surgical approach in a cohort of patients from a single pediatric neurosurgery unit.

METHOD: In a retrospective analysis, all surgical cases, who underwent the supraorbital craniotomy via an eyebrow incision were identified in the time period between January 2013 and April 2022. The craniotomy was performed using piezosurgery ultrasonic bone incision. Orbital pathologies were operated with an interdisciplinary team of orbital surgeon and neurosurgeon. Clinical and surgical characteristics, perioperative data, possible complications or redo surgeries as well as ophthalmologic status were acquired.

RESULTS: The clinical data of 37 cases in 30 patients (age: 7.9 ± 6.6 yrs.) were collected. The supraorbital craniotomy established the access to the cranial, lateral and central portions (n = 19) of the orbit and frontomedial and ipsilateral portions of the skull base (n = 18). 32 patients suffered from tumor disease of whom 14 patient needed adjuvant therapy. Mean duration of surgery was 163 ± 95 min and hospital stay was 6.2 ± 2 days. 5.6% experienced complication of a local infection treated by puncture and antibiotics and an eyelid hematoma resolved spontaneously over time. Cosmetic result was still excellent. Visual function was stable compared to preoperative status in all patients. Long-term outcome of oncology cases was CR in 14, SD in 15, PD in 1 and death in 2 patients.

CONCLUSIONS: The supraorbital eyebrow approach is feasible and safe in pediatric neurosurgical cases and should be considered for intraorbital as well as fronto-basal pathologies especially extending towards the upper lateral quadrant as well as ipsilateral intracranial lesions adjacent to the skull base. Interdisciplinary cooperation enables a broader spectrum of surgical options in complex, frontobasal, skull base pathologies.

Keywords: Orbit, Supraorbital craniotomy, Keyhole surgery, Skull base

FL-004

Germ Cell Tumors

Paediatric pineal region tumours: a surgical case series demonstrating the harmonious use of microscopic and endoscopic approaches

David Rowland¹, Ladina Greuter¹, Anca Vasilica², Ahmed Raslan¹, Cristina Bleil¹, Bassel Zebian¹

¹Department of Paediatric and Adult Neurosurgery, King’s College Hospital NHS Foundation Trust, London, UK

²University College London Medical School, London, UK

BACKGROUND AND AIM: Surgery on pineal region tumours is challenging. Traditionally, this was performed using open microsurgical approaches. Following recent improvements in neuroendoscopic techniques and instrumentation, transventricular approaches have become a useful addition to our armamentarium. Here we describe our experience of microscope, endoscope-assisted and fully endoscopic approaches to pineal region tumours in paediatric patients to demonstrate their harmonious use.

METHOD: Single-centre retrospective case series from 01/09/2014–01/01/2022 of all patients 16 years or younger who underwent microsurgical and/or endoscopic surgery for a pineal region tumour. Endoscopic biopsy/debulking/resection was performed via a transventricular transchoroid approach to the pineal region in combination with endoscopic third ventriculostomy (ETV) for CSF diversion. Open microsurgical resection was performed via the supracerebellar infratentorial (SCIT) or occipital interhemispheric approach.

RESULTS: 10 patients were included, with a mean age of 11.9, all of whom were male. At presentation, all patients had a GCS of 15 and had hydrocephalus. One patient underwent insertion of an external ventricular drain; the remaining 9 underwent either an ETV (1, 10%) or ETV and endoscopic tumour biopsy/debulking/resection (8, 80%). 7 (70%) underwent open microsurgical tumour surgery after their initial endoscopic biopsy and 2 (20%) underwent more than one microsurgical procedure. In one patient the tumour was completely removed using the endoscopic transventricular transchoroid approach. Histopathological analysis of the tumours showed 8 germ cell tumours and 2 pineal parenchymal tumours. Mean post-operative GCS was 13.2, and at discharge all patients were GCS 15. One patient died 187 days after the first surgery due to tumour recurrence and progression.

CONCLUSIONS: This is the first case series describing the combined endoscopic and microsurgical management of paediatric pineal tumours. The majority were managed with a combination of ETV and biopsy as a first procedure followed by a SCIT approach depending on the tumour histology. Complete resection was possible endoscopically in one patient.

Keywords: Pineal, Germ Cell Tumours, Neuroendoscopy, Microscope

FL-005

Neuro-Oncology

11C-Methionine (11C-Met) PET/MRI Imaging Study in children with posterior fossa tumors: a feasibility study

Pierre Aurelien Beuriat¹, Federico Di Rocco¹, Matthieu Vinchon¹, Marc Hermier³, Sylvie Lorthois Ninou², Christian Schaeffer⁴, Anthyme Flaus⁴, Alexandre Vasiljevic⁵, Alexandru Szathmari¹, Carmine Mottolese.¹

¹Pediatric Neurosurgical Unit, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France

²Pediatric Radiology department, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France

³Radiology department, Hôpital Pierre Wertheimer, Hospices Civils de Lyon, Bron, France

⁴Nuclear Medicine department, Hospices Civils de Lyon, Bron, France

⁵Pathology Department, "Groupement Hospitalier Est" Hospices Civils de Lyon, Bron, France

BACKGROUND AND AIM: Magnetic Resonance Imaging (MRI) is the cornerstone of brain tumor evaluation but is not lacking of limitations. Imaging methods capable of providing more reliable and quantitative information on the biological activity of the tumor are necessary. Hybrid PET/MRI imaging has demonstrated its contribution to the management of brain tumors in adults. However, PET data acquired in adult cannot be transposed to children. Thus, due to the lack of studies in children especially in a context of emergency, we aimed to evaluate to feasibility to perform 11C-Methionine (11C-Met) PET/MRI scans pre-operatively in children with a newly diagnosed posterior fossa tumor.

METHOD: From November 2019 to November 2021 all consecutive children admitted in the pediatric neurosurgical unit, Hôpital Femme Mère Enfant, Hospices Civils de Lyon for a newly diagnosed posterior fossa tumor were screened for inclusion. The primary endpoints were: 1) proportion of eligible patient who did have the PET/MRI scanner before the tumor removal, 2) interpretability of the PET/MRI images. The secondary endpoints were: 1) description of the PET/MRI parameter, 2) percentage of eligible patient who gave consent to the study. All participants were imaged on a fully integrated hybrid Biograph mMR PET/MRI 3 T scanner with an intravenous bolus injection of 11C-Methionine.

RESULTS: Fifteen patients were included in the study with a mean age of 8.9 years (min5, max 16) and a 8 to 7 male to female ratio. Five patients did not perform the PET/MRI exams (1 because of a 11C-Met synthesis failure, 4 because of technical/programming issues). There was a significant difference in the Mean SUV and the max SUV value between WHO grade I and IV (p < 0.05.

CONCLUSIONS: Hybrid PET/MRI imaging is a promising technique in the management of pediatric brain tumor. More data are needed to be able to use it in a clinical set up.

Keywords: Posterior fossa tumor, Hydrib PET/MRI, Feasability, Children

FL-006

Neuroendoscopy

Neuroendoscopy for intraventricular tumors

Luca Massimi, Paolo Frassanito, Federico Bianchi, Achille Solimene, Vincenzo Mastropasqua, Gianluca Galieri, Gianpiero Tamburrini

Fondazione Policlinico Universitario A. Gemelli IRCCS

BACKGROUND AND AIM: Thanks to recent progresses, the indication to the endoscopic management of intraventricular tumors (IT) has significantly changed, ranging from the treatment of the hydrocephalus or the biopsy (in the past) to the gross total resection of the tumor (currently). However, some limitations of this surgery are still present, as rich vascularization of the tumor, its paraventricular extension or large size, small ventricles. Herein, we present the personal experience with the pure endoscopic management of intraventricular tumors together with a review of the pertinent literature.

METHOD: All children with IT consecutively managed by purely neuroendoscopic approach in the last 5 years were enrolled for this study. The 2015–2020 time period was considered to have a 2-year minimum follow-up and a homogeneous management (dedicated ultrasound aspirator, laser etc.).

RESULTS: 16 children compose the present series. The M/F ratio was 1.5, the mean age at surgery was 7 years (range: 3–18 years). SEGA (6 cases) craniophryngioma (5 cases), astrocytomas (4 cases), choroid plexus papilloma (1 case) were the treated histotype. The accuracy of the biopsy was complete (100%). Gross total/near total resection of the tumor was realized in 70% of the cases (> 90% when SEGA was operated on). No surgical mortality occurred. The main complications were represented by transient seizures (5 cases), mild intraoperative bleeding (3 cases), subdural hygroma (1 case), closure of a previous ETV (1 case). All patients are alive after a mean 3.8-year follow-up.

CONCLUSIONS: The endoscopic excision of IT is safe and effective as long as a correct indication is given. However, in the literature, the risk of mortality and major permanent morbidity is 2.2% and 3.5%, respectively. Although all IT are a potential indication for neuroendoscopy, currently, some limits must be aknowledged such as diameter > 2.5–3 cm, cisterna invasion, very small ventricles and involvement of the IV ventricle.

Keywords: Intraventricular tumors, neuroendoscopy, children

FL-007

Neuro-Oncology

Multidisciplinary Management of Optic Pathway Glioma in Children with Neurofibromatosis Type 1

Laura Nanna Lohkamp¹, Patricia Parkin², Allan Puran², Ute Katharina Bartels³, Eric Bouffet³, Uri Tabori³, James Thomas Rutka¹

¹Division of Neurosurgery, Department of Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada

²Division of Paediatric Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada

³Division of Haematology / Oncology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada

BACKGROUND AND AIM: Neurofibromatosis type 1 (NF1) is in 15% is associated with optic pathway glioma (OPG). Given its variability in clinical presentation, a multidisciplinary approach for diagnosis and management is required, but often lacks coordination and regular information exchange. Herein we summarize our experience in treating children with NF-1 and OPG and describe the provided multidisciplinary care network including the roles of the distinct team members.

METHOD: We performed a retrospective single-center observational study, including children treated between 1990 and 2021. Inclusion criteria were clinical diagnosis of NF1, radiographic and/or histopathological diagnosis of OPG and age below 18 years. Data were abstracted from each child’s health record using a standardized data collection form. Patient characteristics were described using means (SD) and percentages. Outcomes were determined using Kaplan–Meier estimates.

RESULTS: From 1990 to 2021, 1337 children were followed in our institution. Of those, 195 were diagnosed with OPG (14,6%), including 94 (48.21%) females and 101 (51.79%) males. Comprehensive data were available in 150 patients. The mean (SD) age at diagnosis was 5.31(4.08) years (range: 0.8—17.04 years). Sixty-two (41.3%) patients remained stable and did not undergo treatment, whereas 88 (58.7%) patients required at least one treatment. The mean (SD) duration of follow up was 8.14 (5.46) years (range: 0.1–25.9 years; median 6.8 years). Overall survival was of 23.6 years (± 1.08), comprising 5 deaths. A dedicated NF clinic provides regular follow up and plays a central role in the management of children with NF1, identifying those at risk of OPG, coordinating referrals to Neuroradiology and other specialists as indicated. Comprehensive care was provided by a multidisciplinary team consisting of Dermatology, Genetics, Neuro-oncology, Neuroradiology, Neurosurgery, Ophthalmology and Pediatrics.

CONCLUSIONS: The care of children with NF1 and OPG is optimized with a multidisciplinary team approach, coordinated by a central specialty clinic.

Keywords: Optic pathway glioma, Neurofibromatosis type 1, Diagnosis, Management, Multidisciplinary

FL-008

Neuro-Oncology

Defective and downregulated mitochondria in pediatric craniopharyngiomas

Engy Abd El Rahman¹, Basma Yassen¹, Aya El Khodiry¹, Eman Khorshid³, Mohamed El Beltagy², Sameh Ali¹

¹Department of Neurosurgery Children’s Cancer hospital Egypt

²Department of basic research Children’s Cancer hospital Egypt

³Department of Pathology Children’s Cancer hospital Egypt

BACKGROUND AND AIM: INTRODUCTION: Adamantinomatous craniopharyngiomas (ACPs) are benign tumors that are associated with high morbedity and the lowest quality of life scores relative to any other pediatric brain tumor. This is mainly due to their close proximity to many vital structures, tendency for cyst formation and hypothalamic infiltration that predispose many children to a life of serious disability. Although complete resection of the tumor remains the mainstay of treatment and is associated with a > 85% progression-free survival rate, the potential for postoperative recurrence of ACP is very high. Evidence are clustering around an important role of inflammatory processes and immune response in the patholgy of ACP but whether these factors are contributors to the ACP tumorgenesis is enigmatic. Hypothesizing that mitochondrial defects and mitochondrial mediated oxidative stress are important players in the ACP pathogenesis we conducted a pilot study exploring mitochondrial functions in freshly excised ACP tumors.

METHODS: We used high-resolution oximetry, fluorescence imaging and microscopy, in addition to molecular techniques to interrogate mitochondrial respiratory function and ROS production.

RESULTS: Interestingly, we discovered that mitochondrial complex I is completely scilent thus leaving the ROS-leaky complex II as the only bioenergetic entry to the electron transport chain (ETC) in ACP tumors. We also analyzed mitochondrial protein expression levels of the electron transport chain complexes which were found significantly downregulated in ACP tumors relative to HEK cells. Moreover, a significant dependence of ACP tumors on ROS-producing fatty acid metabolism is readily observable. Indeed, fluorescence imaging indicated that relative to HEK cells, primary cells derived from ACP tumor exhibited remarkably higher cellular and mitochondrial ROS. The role of defective mitochondria in Wnt-signaling pathway and accumulation of β-catenin is currently under investigation.

CONCLUSIONS: Current preliminary data places mitochondria at the root causes of the ACP tumor origination and possibly recurrance.

Keywords: Mitochondria, Adamantinomatous craniopharyngioma

FL-009

Neuro-Oncology

A comparison of intraoperative ultrasound and postoperative MRI in paediatric intra axial tumours

Nadiah Ahmad Fuad¹, Azmi Alias¹, Fadzlishah Johanabas Rosli¹, Lim Mei Sin¹, Rohazly Ismail², Adi Afiq Md Anour²

¹Department of Neurosurgery, Hospital Tunku Azizah, Kuala Lumpur, Malaysia

²Department of Radiology, Hospital Tunku Azizah, Kuala Lumpur, Malaysia

BACKGROUND AND AIM: Malignant tumours of the Central Nervous System (CNS) is the second most common paediatric malignancy, following haematological malignancy. CNS tumours depend significantly on the extent of tumour resection. In the past decade, intraoperative ultrasound (IOUS) has evolved into a widespread neuroimaging tool that offers real-time surgical guidance, and is a widely accessible imaging modality with minimal identified risk or additional operative time, and also lower economic investment. The objective of our study is to compare correlation and reliability of the ultrasound as compared to MRI for tumour resection in paediatric population. We also evaluated IOUS as a real-time navigation tool during surgical resection of intra axial tumours in paediatric patients.

METHOD: This is a prospective observational study done in a Hospital Tunku Azizah, Kuala Lumpur. Patients aged less than 12 years old, admitted between 1st December 2019 to 30th November 2021 with preoperative MRI diagnosis of intra-axial brain tumour were recruited in this study. IOUS was performed intraoperatively, and post-operative MRI performed within 24–72 h post-op. IOUS utility assessment scoring was performed intraoperatively.

RESULTS: We analysed a total of 25 paediatric patients that met the inclusion criteria. Concordance analysis between IOUS evaluation and MRI showed good agreement (kappa = 0.527). A multivariate logistic regression analysis was performed to look for any significant factors of discordance, and none of the variables were found significant for discordance. Hosmer and Lemeshow goodness of fit test was performed, and showed that our model is a good fit, with a good prediction value of 0.497.

CONCLUSIONS: The use of IOUS may allow reliable intra operative imaging modality to achieve more successful gross total resection of brain tumours in paediatrics.

Keywords: Intraoperative ultrasound, Realtime navigation, Paediatric tumours, Intra axial, Post operative MRI

FL-010

Neuro-Oncology

The use of novel in vitro models to study Adamantinomatous Craniopharyngioma disease biology and drug response

Eric W. Prince¹, Oscar Chatain², Keanu Chee², Stephen Medlin², James Johnston⁴, Roy Dudley³, David Limbrick⁵, Joshua Chern⁹, Robert Naftel¹⁰, Toba Niazi¹³, Annie Drapeau¹⁴, Neil Feldstein⁶, Richard C.E. Anderson¹², Eric Jackson¹¹, Lindsay Kilburn⁸, Kevin Ginn⁷, Amy Smith¹⁵, Sandi Lam¹⁶, Todd C. Hankinson¹

¹Children's Hospital Colorado and University of Colorado School of Medicine, Aurora, USA

²University of Colorado School of Medicine, Aurora, USA

³Montreal Children's Hospital, Montreal, Canada

⁴Childrens Hospital of Alabama, Birmingham, USA

⁵St. Louis Children's Hospital, St. Louis, USA

⁶Children's Hospital of New York, New York, USA

⁷Mercy Children's Hospital, Kansas City, USA

⁸Children's National Medical Center, Washington D.C., USA

⁹Children's Healthcare of Atlanta, Atlanta, USA

¹⁰Monroe Carrell Children's Hospital, Nashville, USA

¹¹Johns Hopkins Medicine, Baltimore, USA

¹²Hassenfeld Children's Hospital at NYU Langone, New York, USA

¹³Miami Children's Hospital, Miami, USA

¹⁴Nationwide Children's Hospital, Columbus, USA

¹⁵Orlando Health Arnold Palmer Hospital for Children, Orlando, USA

¹⁶Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, USA

BACKGROUND AND AIM: Challenges around the design and investigation of cell culture models of ACP have arisen from the cellular heterogeneity of these tumors, with populations that harbor disparate requirements in culture. Novel approaches to in vitro modeling of ACP are needed.

METHOD: Intraoperatively collected tumor specimens were mechanically digested, and plated under conditions tailored to the cell population of interest. ACP tumor derived fibroblasts and epithelial cells were isolated using serum-containing and keratinocyte-specific media respectively. Cell line validation included immunofluorescence with markers appropriate for the cell population of interest. Genomic signatures generated using qPCR were compared to a novel single cell RNAseq dataset of ACP tumor tissue.

RESULTS: ACP fibroblasts and ACP epithelial cells maintained spindle-like and cobblestone morphologies respectively, even after passaging. Immunofluorescence confirmed high levels of Vimentin expression in ACP-derived fibroblasts, and panCK and B-catenin in ACP-derived epithelial cells. Point mutation in exon 3 of the CTNNB1 gene was identified in ACP-derived epithelial cells. STR analysis indicated each cell line to be genetically unique.

CONCLUSIONS: Initial limits related to cell line development in ACP may be addressed through the isolation and culture of specific ACP cell populations. This experience demonstrates the maintenance of validated marker of the cell populations of interest ex vivo. While preliminary, such cell lines offer promise as tools for the identification and study of potential therapeutic vulnerabilities in ACP.

Keywords: Craniopharyngioma, Cell culture, Ex vivo culture, Pediatric craniopharyngioma

FL-011

Neuro-Oncology

Novel model for pediatric glioma: H3K27M tumor with inducible TGFB/LAG3 immunotherapy

Vladimir A Ljubimov¹, Sara Sabet², Paul W Linesch², David Rincon Fernandez Pacheco², Shaunt Mehdikhani², Viktoria O Krutikova³, Moise A Danielpour¹, Joshua J Breunig²

¹Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, United States of America

²Department of Regenerative Medicine, Cedars-Sinai Medical Center, Los Angeles, California, United States of America

³Tuoro University School of Medicine, Henderson, Nevada, United States of America

BACKGROUND AND AIM: Gliomas are considered immunologically “cold” tumors that mask themselves from the immune system. Immunotherapy, a breakthrough for cancer treatment, remains inefficient for gliomas. H3K27M mutant diffuse midline glioma has poor survival. Using our innovative mosaic analysis with dual recombinases technology (Cell 2019), we further created a novel murine model of H3K27M glioma with an inducible expression of LAG3 and TGFBR2 to make the tumor recognizable by the immune system. This allows studying molecular mechanisms of “perfect” immunotherapy in pediatric gliomas with histone H3.3 mutations.

METHOD: To make a novel murine model, H3K27M plasmids with doxycycline-inducible expression for TGFBR2 and LAG3 were designed, sequenced, and replicated. For in vitro validation, murine neuronal stem cells were nucleofected with these plasmids, grown and sorted. Doxycycline was added to the experimental group in vitro to induce expression. The plasmids were then electroporated into neonatal MGMT mice (n = 21) of both genders. Control mice were used on a standard diet (n = 9) and experimental mice (n = 12) were given doxycycline in food to induce TGFBR2 and LAG3 expression in vivo. Mice were followed up for survival.

RESULTS: Plasmid sequencing validation demonstrated their high purity. In vitro nucleofected neuronal stem cells showed significant increase in TGFBR2 and LAG3 expression by immunofluorescent staining after addition of doxycycline. The mouse survival study showed a significant benefit with treatment group surviving 46% longer (135 ± 41.9 days vs. 92.6 ± 32.7 days in the control group, p = 0.030).

CONCLUSIONS: We have successfully modified H3K27M glioma to have inducible expression of TGFBR2 and LAG3 to simulate “perfect” immunotherapy. The survival study showed a significant survival benefit. The development of organoid transplants for more uniform testing is ongoing. This can lead to the emergence of novel immune therapies and uncover novel mechanisms of tumor response to treatment.

Keywords: Glioma, H3K27M, Immunotherapy, LAG3, TGFBR2, Model

FL-012

Germ Cell Tumors

Surgical Approaches for Pineal Region Tumors: 151 pediatric cases

Sergio Cavalheiro, Linoel Curado Valsechi, Marcos Devanir Silva Da Costa, Paricia Alessandra Dastoli, Jardel Mendonça Nicácio, Andrea Maria Cappellano, Nasjla Saba Da Silva, Silvia Toledo Caminada, Lorena Pavon, Tatiana Sibov

Neurosurgery Department, Escola Paulista de Medicina, Universidade Federal de São Paulo. Neuro-Oncology, Instituto de Oncologia Pediatria, GRAACC, São Paulo—SP, Brazil

BACKGROUND AND AIM: Analyze the difference between the main surgical approaches for pineal region tumors in children regarding overall survival, progression free-survival, improvement of the surgical technique during the last 30 years.

METHOD: Retrospective analysis of 151 medical records of children with pineal region tumors treated at GRAACC in São Paulo between 1991–2020.

RESULTS: Prevalence of tumors in the pineal region was 7.32%. Germinomas were the most frequent tumors with 33.1%, followed by non-germinomatous germ cell tumors (NGGCT) 27%, pinealoblastomas 22.5%, gliomas 12.5% and embrionary tumor 3.3%. These 151 patients underwent 194 surgical procedures, from those 70 biopsies, 63 infratentorial supracerebellar approaches, 28 occipito-transtentorial approaches, and 33 other approaches. Total resection was achieved in 69%, surgical mortality of 0,6%. Eighty two percent of the patients underwent endoscopic biopsy, the sensibility of the biopsy was 90%. There was statistical diference between the surgical approaches regarding of mortality, morbidity, grade of resection or progression-free-survival in 5 years. The overall survival in 5 years was compared between the three decades, the first (1991–2000) presented OS of 76% in 5 years, the second (2001–2010) OS 53% in five year, and the third (2011–2020) presented OS of 77% in 5 years. Progression-free-survival in 5- years in germinomas was 77%, NGGCT 50%, pinealoblastoma 38.9%, glioma 72.6%.

CONCLUSIONS: Pineal region tumors require a multimodal approach in which surgery plays important role. The best approach depends on size of the lesion, direction of the lesion’s growth and surgeon’s skills.

Keywords: Pineal region tumor, Supracerebellar infratentorial approach, Occipto transtentorial approach, Endoscopic biopsy

FL-013

Neuro-Oncology

Survival and Neurological Outcomes after Stereotactic Biopsy of Diffuse Intrinsic Pontine Glioma: A Systematic Review

Prottusha Sarkar¹, Sunny Abdelmageed¹, Manasa Pagadala¹, Nathan A. Shlobin¹, Mandana Behbahani², Melissa A. LoPresti³, Sandi Lam², Michael DeCuypere²

¹Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA

²Division of Pediatric Neurosurgery, Ann and Robert H Lurie Children's Hospital of Chicago, Chicago, IL, USA

³Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA

BACKGROUND AND AIM: Diffuse intrinsic pontine gliomas (DIPG) are aggressive and malignant tumors of the brainstem. Stereotactic biopsy helps obtain molecular and genetic information for diagnostic and potentially therapeutic purposes. However, there is no consensus on the safety of biopsy nor effect on survival. We aimed to characterize neurological risk associated with and the effect of stereotactic biopsy on survival among patients with DIPG.

METHOD: A systematic review was performed in accordance with PRSIMA guidelines to identify all studies examining pediatric patients undergoing stereotactic biopsy with DIPG. Bibliographic, demographic, clinical, and outcome data were extracted from studies meeting inclusion criteria.

RESULTS: Of 569 resultant articles, 14 were included. A total of 384 patients underwent biopsy. Of these biopsies, children had a weighted mean age of 7.2 years (range 4.8–8.8) at diagnosis. There was an overall complication rate of 25.5% (98/384), of which 51% (50/98) were neurological complications. The most common neurological complication was cranial nerve palsy (40%, 20/50), of which cranial VII was the most common (40%, 4/10). Hemiparesis (38% of neurologic complications) was also frequently reported. Dysarthria, dysphasia, and dysphagia were also notable. Diagnostic yield of biopsy was 92% (range 71–100%). Of the studies reporting survival data, 105 patients (30.9%) died within study follow-up periods (range 1 to 35.9 months). The mean overall survival was 10.2 months (SD = 1.88, Median = 10.3, range = 9–20.4 months). Progression-free survival (PFS) was a mean of 6.75 months (SD = 1.25, Median = 6.5, range = 5.6–8.4 months). No morbidity was specifically attributed to biopsy.

CONCLUSIONS: Children with DIPG undergoing brainstem biopsy have low rates of neurologic deficits and no excessive morbidity. With quantification of relatively low surgical risk in this morbid condition, the rationale for tissue biopsy is that ongoing characterization of patient-specific, molecular, and genetic factors influencing prognosis will improve risk stratification and catalyze the development of therapeutic strategies.

Keywords: Brainstem biopsy, Dipg, Stereotactic biopsy, Diffuse intrinsic pontine glioma, Stereotactic, Pediatric brain tumor

FL-014

Neuro-Oncology

Impact of the COVID-19 pandemic on 30-day mortality and unplanned reoperation rates for pediatric central nervous system tumors

Diana Jovett Sanchez¹, Ceri Jane Homillano Talan², Sally Andrea Dunton Gaspi³, Ana Patricia Angeles Alcasabas², Ronnie Enriquez Baticulon¹

¹Division of Neurosurgery, Department of Neurosciences, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines

²Section of Hematology and Oncology, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines

³Section of Pediatric Neurology, Department of Pediatrics, University of the Philippines Manila, Manila, Philippines

BACKGROUND AND AIM: Unplanned reoperations and mortality within 30 days are important indicators when evaluating the quality of care provided by surgical systems. We reviewed these outcomes among children with primary central nervous system (CNS) tumors treated during the COVID-19 pandemic.

METHOD: This is a retrospective study of all pediatric patients who underwent neurosurgery for primary CNS tumors at the Philippine General Hospital, the national university hospital, from January 1, 2020 until December 31, 2021. Their clinical presentation, perioperative course, and outcomes were analyzed. During this time, our hospital concurrently served as a COVID-19 referral center, thus, the workforce was restructured, and resources were reallocated to care for COVID-19 patients.

RESULTS: A total of 92 pediatric patients with CNS tumors underwent 140 neurosurgical operations during the study period. Two-thirds of the patients were males, and mean age was 9.3 ± 5.0 years (range: 3 months to 18 years). Average preoperative length of stay was 3.9 ± 2.6 days. Tumor resection was performed in 73 patients (79%). Most common histologic diagnoses were medulloblastoma (20%) and low-grade glioma including pilocytic astrocytoma (20%). Overall, the 30-day mortality and unplanned reoperation rates were 12% and 22%, respectively. Eight patients died from brain herniation and/or tumor progression. Reasons for unplanned reoperations were postoperative hydrocephalus (20%), infection (9%), hematoma (7%), and tumor residual (3%).

CONCLUSIONS: Worldwide, the COVID-19 pandemic has altered hospital protocols and shifted resources considerably. The observed high rates of death and reoperation are likely due to delays in seeking care leading to worse neurologic status at presentation, delays in performing essential surgery within the hospital, and shortage of health workers providing specialist care. It is important to periodically assess perioperative outcomes to improve the quality of surgical care given to children with CNS tumors, who remain a vulnerable population during the COVID-19 pandemic.

Keywords: COVID-19, Pandemic, Mortality, Reoperation, Pediatric central nervous system tumors, 30-day mortality

FL-015

Neuro-Oncology

Evolution of surgical management of pineal region tumors in the pediatric population: a 17-year experience at a single institution

Hasan Raza Syed¹, Nirali Patel², Alexandria Marino³, Kelsey Chesney², Katherine Hoffmann¹, Daniel Donoho¹, Chima Oluigbo¹, Robert Keating¹, John Myseros¹

¹Department of Neurosurgery, Children’s National Hospital, Washington DC

²Department of Neurosurgery, MedStar Georgetown University Hospital, Washington DC

³Georgetown University School of Medicine, Washington DC

BACKGROUND AND AIM: Pineal region tumors have historically been challenging to treat. Advances in surgical techniques have led to significant changes in care and outcomes for these patients. Here, we describe a single institution’s experience over a 17-year-period and the evolution of diagnosis, treatment, and outcomes of pineal tumors in pediatric patients.

METHOD: We retrospectively collected data on all pediatric patients with pineal region lesions treated with surgery at Children’s National Hospital (CNH) from 2005–2021. Variables analyzed included presenting symptoms, presence of hydrocephalus, diagnostic and surgical approach, pathology, and adverse events, among others.

RESULTS: A total of 43 pediatric patients with pineal region tumors were treated during a 17-year period. Most tumors in our series were germinomas (n = 13, 29.5%) followed by pineoblastomas (n = 10, 22.7%). 27 of the 43 patients (62.8%) in our series received a biopsy to establish diagnosis, and 44.4% went on to have surgery for resection. The most common open approach was posterior-interhemispheric (PIH, transcallosal). Gross total resection was achieved in 50%; recurrence occurred in 20.9%; and mortality in 11% over a median follow-up of 47 months. Endoscopic third ventriculostomy (ETV) was employed to treat hydrocephalus in 26 of the 38 patients (68.4%) and was significantly more likely to be performed from 2011–2021. No difference was found in recurrence rate or mortality in patients who underwent resection compared to those who did not, but complications were more frequent with resection. There was disagreement between frozen and final pathology in 18.4% of biopsies.

CONCLUSIONS: This series describes surgical approaches and outcomes over a 17-year-period. Complication rates were higher with open resection, reinforcing the safety of pursuing endoscopic biopsy as an initial approach. The most significant changes occurred in the preferential use of ETVs over ventriculoperitoneal shunts. In our series, outcomes of these patients have not significantly changed over that time.

Keywords: Pineal tumors, Endoscopic third ventriculostomy, ETV, Hydrocephalus, Biopsy, Resection

FL-016

Neuro-Oncology

Robotic alignment system Cirq (Brainlab) for navigated brain tumor biopsies in children

Kirsten Van Baarsen¹, Darwin Woodley¹, Mariam Slot², Peter Woerdeman¹, Sen Han¹, Eelco Hoving¹

¹Princess Máxima Center for Pediatric Oncology, department of neurooncology, Utrecht, the Netherlands; Wilhelmina Children's Hospital, department of neurosurgery, Utrecht, the Netherlands

²Amsterdam University Medical Center, Amsterdam, the Netherlands

BACKGROUND AND AIM: With the incorporation of the robotic alignment system Cirq (Brainlab, Munich, Germany) into our neurosurgical armamentarium, we deemed it important to study the application accuracy of this new device. As a baseline, we retrospectively reviewed our historical data on brain tumor biopsies with the non-robotic alignment instrument Varioguide (Brainlab, Munich, Germany). We also sought to improve our registration when we introduced Cirq.

METHOD: All patients (0–19 years old) who underwent a brain tumor biopsy at the Princess Máxima Center, Utrecht, were included. Over the period 2019–2020, data were collected retrospectively (cohort “Varioguide” in which patient-to-image registration was based on preoperative MRI with adhesive skin fiducials). From 2021 onwards, data were collected prospectively (cohort “Cirq”). For both cohorts, Euclidian distances and in-plane distances were calculated between the intended target and the obtained target using postoperative MRI scans (“target error”, TE).

In some patients from the “Cirq” cohort, patient-to-image registration was done using 1. a preoperative MRI with adhesive skin fiducials and 2. an intraoperative CT scan with bone screw fiducials. The registration errors of both methods were compared.

RESULTS: Twenty-three patients were biopsied with Varioguide and twelve patients with Cirq. The Cirq robotic system, combined with bone fiducial registration, resulted in a high target accuracy with a maximum target error of 2,1 mm, as compared to 3,8 mm for Varioguide (difference not significant). However, patient-to-image registration was significantly more accurate when based on bone screw fiducials as compared to skin fiducials.

CONCLUSIONS: The Cirq robotic alignment system is convenient and safe. Although Cirq seems more precise than Varioguide, the sample size was too small to reach statistical significance. Patient-to-image registration is significantly more accurate with bone screws as compared to skin fiducials. Registration based on adhesive skin fiducials does not offer the level of precision that is mandatory for brainstem tumor biopsies.

Keywords: Cirq—robotics—biopsy—brain tumor—target accuracy—pediatrics

FL-017

Neuro-Oncology

Choroid plexus tumours: a study on prognosticating factors on clinical and educational outcome

John Ong¹, Rishil Patel¹, Pasquale Gallo², Desiderio Rodrigues², Richard Walsh², Guirish Solanki², William B Lo²

¹College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK

²Department of Paediatric Neurosurgery, Birmingham Children’s Hospital, Birmingham, UK

BACKGROUND AND AIM: The optimal management of choroid plexus tumours (CPTs) of various grades is unclear, because of their rarity, young age of presentation, variable gross total resection (GTR) rate and the challenging risk/benefit balance regarding adjuvant therapy. Most patients require cerebrospinal fluid shunt insertion. This study investigates the clinical, oncological, and surgical factors affecting clinical outcomes.

METHOD: 15-year retrospective study (2006–2021). Patient demographics, tumour characteristics and treatment data were collected. Event-free survival [EFS] was performed using Kaplan–Meier analysis and compared with log-rank test. Events were defined as recurrence or death from disease.

RESULTS: Seventeen patients were included. The 9 patients with choroid plexus papillomas (WHO grade I) had a 5-year EFS of 89%(8/9). The one event was in the only child who did not have GTR of her bilateral ventricular lesions and received adjuvant therapy; her tumour regrew 2 years following surgery. Out of the 5 atypical choroid plexus papilloma (II), and 3 choroid plexus carcinoma (III) cases, 50%(4/8) achieved GTR and one mortality occurred at 6 months of a child with a partially resected grade II tumour. Shunt insertion rates were greater in grade I than grade II/III tumours (6/9 vs 4/8), as well as shunt revision rates (4/6 vs 1/4). All 5 patients receiving preoperative embolisation achieved GTR, compared to 58%(7/12) of patients not undergoing embolisation. Where data were available, three children out of eight attended special educational needs schools, all of whom had Grade I disease. The same 2 of the 3 children developed post-operative epilepsy and had shunt insertion.

CONCLUSIONS: Children with choroid plexus papillomas treated with surgery alone achieved a high EFS. 8 children with grade II/III disease, who received adjuvant therapy following surgery, based on an individualised approach, achieved a 75% EFS and 88% overall survival. Post-operative epilepsy and shunt may be associated with poorer cognitive and educational outcome.

Keywords: Choroid plexus tumour, Gross-total resection, Adjuvant therapy, Event-free survival, Educational outcome

FL-018

Neuro-Oncology

Navigated Transcranial Magnetic Stimulation in Pediatric Brain Tumor Surgery

Ladina Greuter, Sabina Patel, Cristina Bleil, Bassel Zebian, Francesco Vergani, Jose Lavrador

Department of Neurosurgery, King's College Hospital NHS Foundation Trust, London, United Kingdom

BACKGROUND AND AIM: Transcranial Magnetic Stimulation (TMS) is a diagnostic tool increasingly used in neurosurgery for identification of motor and language eloquent regions prior to surgical intervention. Although commonly utilised and well tolerated in adult patients, there is little data regarding the tolerability and accuracy of data in paediatric patients. This study evaluates the safety, tolerability, and accuracy of TMS in paediatric patients.

METHOD: Using the trust patient database, we identified all paediatric patients (< 18 years) who underwent TMS for pre-surgical evaluation of motor and/or language eloquent areas between 1.1.2019-0.1.12.2021. Electronic patient records were reviewed to confirm demographical data including histological diagnosis.

RESULTS: A total of 7 patients were identified who underwent TMS for pre-surgical mapping of motor and/or language eloquent areas (motor = 6, language = 1). Mean age was 13.57 (± SD 3.74, range 7–18 years), with four (57%) male patients. Four tumours (57%) were located in the parietal region, three (43%) in the temporal lobe and one was a brainstem tumour. All patients tolerated the full extent of the mapping. No TMS related complications were observed either during or following the exam. One patient developed postoperative hydrocephalus, which was treated with an endoscopic third ventriculostomy on the third postoperative day. Postoperative histology resulted in six (86%) high grade gliomas (WHO IV) and one ependymoma RELA fusion positive (WHO II). None of the patients had a significant drop of motor or sensory evoked potentials intraoperatively.

CONCLUSIONS: Diagnostic TMS for pre-surgical motor and language mapping was shown to be tolerable in the paediatric population with no immediate or lasting complications. Furthermore, the cortical excitability score calculated from TMS can positively predict tumour grading and facilitate early discussions regarding neurological recovery, diagnosis, and treatment.

Keywords: Transcranial magnetic stimulation, TMS, Pediatric brain tumor, Neurooncology

FL-019

Neuro-Oncology

Semisitting position for posterior fossa tumors in children

Oscar Garcia González, Oscar Guerrero, Edgard Lozada Hernandez, Sergio Orozco Ramirez

Hospital Regional de Alta Especialidad del Bajio

BACKGROUND AND AIM: The semi-sitting position is one of the preferred positions for resection of posterior fossa midline tumors. Nevertheless, it harbors some risks, with the most dreaded beeing air embolism. In small children another additional risk is rigid head fixation. Here we report about our experience with the semi-sitting position in children.

METHOD: Nineteen children younger than 17 years of age were operated in the semi-sitting position (mean age: 6.5 years; range between 1.8 m and 16y). Persistent foramen ovale was excluded preoperatively in 15/19 patients. Intraoperative incidents were recorded and patients course followed postoperatively with a special focus on possible complications.

RESULTS: The histopathological diagnoses included ependymoma (n = 5), pilocytic astrocytoma (n = 2), exofitic brainstem glioma (n = 2), medulloblastoma (n = 10). CSF shunt/ETV were done in 17 of 19 children who presented with hydrocephalus preoperatively. No major intraoperative complications occurred. Air embolism was detected in 2 patients during surgery, the air embolism was recorded in TEE without cardiovascular or respiratory signs or symptoms. In one patient arterial hypotension with reduction of pCO2 occurred and it was treated successfully with chatacholamin infusion and suction of air embolism via a central venous catheter without postoperative complications due to the embolism. Postoperatively all children showed pneumocephalus and one of them developed a subdural hygroma and was treated by burr-hole drainage. Revision surgery was necessary in one child with subtotal resection. Only one child did not require any surgical diversion because of presenting hydrocephalus pre or postoperative tumor resection (ETV or ventriculoperitoneal shunt).

CONCLUSIONS: The semi-sitting position for tumor resection of the posterior fossa in children under 16 years of age entails certain risks, however, it can be successfully performed taking special caution to detect and treat potential complications in an interdisciplinary teamwork with specialized neuroanaesthesiologists.

Keywords: Posterior fossa tumors, Semisitting position, Foramen ovale, Venous air embolism

FL-020

Neuro-Oncology

Cerebellopontine angle tumours in the pediatric population – An original series of 43 patients

Amr Abdelhakam¹, Sandro Benichi¹, Arnault Tauziède Espariat², Pascale Varlet², Christelle Dufour³, Jacques Grill³, Léa Guerrini Rousseau³, Samuel Abbou³, François Doz⁴, Franck Bourdeaut⁴, Nathalie Boddaert⁵, Christian Sainte Rose¹, Stephanie Puget¹, Thomas Blauwblomme¹, Kevin Beccaria¹

¹Pediatric Neurosurgery Department, Necker Enfants Malades Hospital, Paris Cité University, Paris, France

²Department of Neuropathology, Sainte-Anne Hospital, GHU Paris Neurosciences, Paris, France

³Department of children and adolescent oncology, Gustave Roussy, Villejuif, France

⁴SIREDO Center (Care, research, innovation in pediatric, adolescent and young adult oncology), Institut Curie, Paris, France; Université Paris Cité, Paris, France

⁵Pediatric Neuroradiology Department, Necker Enfants Malades Hospital, Paris Cité University, Paris, France

BACKGROUND AND AIM: Posterior fossa tumours account for almost 40 to 50% of brain tumours in children, but less than 10% are in the cerebellopontine angle (CPA). We aimed to report characteristics and surgical management of CPA tumours in a referral center.

METHOD: Patients less than 18 years old treated for a CPA tumour from 2010 to 2020 at Necker Enfants Malades Hospital were retrospectively included. CPA tumours were defined as tumours entirely or predominantly developed in the CPA. Clinical, radiological, histological, and surgical data were collected. Statistics were performed with BiostaTGV, based on R software.

RESULTS: Forty-three patients were included (median age = 6.9 years; 7 days—16.5 years). The most frequent symptoms leading to diagnosis were facial nerve palsy (25%), hearing loss (25%), and intracranial hypertension (18.41%). Hydrocephalus was observed in 20 cases (46.5%) and was treated before tumour resection in 14/20 cases (shunt, endoscopic third ventriculostomy, cyst puncture or debulking in emergency). Tumour resection was performed in 37/43 cases (partial = 23; complete = 14). The tumour was malignant in 20/37 cases. The most frequent histology were ATRT (n = 6), neurinoma (n = 6) and pilocytic astrocytoma (n = 5). Patients with a benign tumour were significantly older than those with a malignant tumour: 9.1 years vs 4.7 years, respectively (p = 0.007). After surgery, improvement or stability of cranial nerve palsy was observed in 14/37 cases and permanent worsening in 2 cases. Most common long-term sequelae were facial palsy, hearing loss, and swallowing disorders.

CONCLUSIONS: CPA tumours are a rare entity in children. The histological findings are diverse. The surgical strategy must consider the age of patient, the existence of hydrocephalus at diagnosis and the histology. Monitoring of the cranial nerves should become systematic to limit complications and to optimise tumour resection.

Keywords: Cerebellopontine angle, Tumor cranial nerves, Hydrocephalus

FL-021

Vascular

Gamma Knife Radiosurgery for Pediatric Brain Arteriovenous Malformation: a Single Institute experience of 40 patients

Jun Kyu Hwang¹, Eun Kyung Park², Kyu Won Shim², Dong Seok Kim², Won Seok Chang³

¹Department of Neurosurgery, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin, Korea

²Department of Pediatric Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea

³Department of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea

BACKGROUND AND AIM: This study investigated the factors contributing obliteration of brain arteriovenous malformations (AVM) in pediatric patients who underwent Gamma Knife Radiosurgery (GKRS).

METHOD: From Jan 2001 to Aug 2021, 40 pediatric patients (23 male and 17 female) underwent GKRS for bAVMs. The median age was 7 ± 3 years old (range: 2–19) and volume was 2.4 ± 9.7 cm3 (range: 0.3–51.6). Marginal dosage was 16 ± 1.4 Gy (range: 13–18) at 50% iso-dose curve line. Follow-up MRI was requested at 6 months, and then annually. Digital Subtraction Angiogram (DSA) was performed to investigate complete obliteration. Each factor associated with complete obliteration was analyzed.

RESULTS: The median follow up period was 25 ± 30 months (range: 5–157). Twenty-three patients (54.8%) showed complete obliteration and no new deficit. Sex, age, volume, AVM type, hemorrhage, location, AVM grade, AVM score were.

analyzed using Cox proportional hazard model. AVM volume over 3cm3 has 4.3 times higher rate of residual nidus (p = 0.009). The modified rankin score showed that 30 patients (70.5%) lived without symptoms or no significant disability after GKRS. One patient (2.5%) underwent rebleeding and two patients (5%) underwent recurrence.

CONCLUSIONS: This study revealed that GKRS for pediatric bAVMs is a safe and effective treatment considering the high obliteration rate and acceptable risk of radiation-induced complication. Volume below 3cm3 is an important factor for expecting obliteration.

Keywords: Arteriovenous malformation, Radiosurgery, Stereotactic

FL-023

Vascular

Spontaneous thrombosis of VOG malformation managed with surgical resection: a case-based review

Yahya H Khormi

Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Jazan University, Jazan, Saudi Arabia

BACKGROUND AND AIM: Vein of Galen (VOG) malformation is a rare congenital intracranial vascular malformation. Spontaneous thrombosis of this lesion is extremely rare.

METHOD: The author reports a clinical presentation, images as well as surgical management of a child diagnosed with Spontaneous thrombosis of VOG malformation. Furthermore, a literature review of all published cases was conducted and summarized.

RESULTS: A 2-year- old boy presented with symptoms and signs secondary to mass effect, hydrocephalus, and high Intracranial Pressure (ICP). Location of the lesion was off the pineal region which make it atypical for VOG malformation. Patient was managed successfully with surgical resection and intra-operative finding and pathology confirmed the diagnosis of spontaneous thrombosis of VOG malformation. Patient had a complete neurological recovery at follow up. A literature review revealed only eleven cases were reported, clinical presentation included: headache, irritability, vomiting, seizures, 6th nerve palsy, hemiparesis and decrease in level of consciousness. Six patients underwent surgical excision of aneurysm, four patients underwent CSF diversion and two patients underwent both. The overall outcome was good.

CONCLUSIONS: Spontaneous thrombosis of VOG malformation is a rare pathology. It is associated with delayed and variable clinical presentations likely due to low flow shunt mural type VOG malformation. It has a favorable prognosis with surgical treatment.

Keywords: Vein of Galen malformation, Arteriovenous malformation, Aneurysm, Spontaneous thrombosis, Surgical resection

FL-025

Vascular

Long-term health-related quality of life in patients with ruptured arteriovenous malformations treated in childhood

Elias Oulasvirta¹, Anni Pohjola¹, Päivi Koroknay Pál¹, Ahmad Hafez¹, Risto Roine², Harri Sintonen³, Aki Laakso¹

¹Department of Neurosurgery, Helsinki University Hospital, Helsinki, Finland

²Department of Health and Social Management, University of Eastern Finland, Kuopio, Finland

³Department of Public Health, Helsinki University Hospital, Helsinki, Finland

BACKGROUND AND AIM: To reveal the long-term health-related quality of life (HRQoL), educational level, and impact on occupation in 55 ruptured and treated pediatric brain arteriovenous malformation (AVM) patients.

METHOD: In 2016, questionnaires including the 15D instrument were sent to patients over 18 years of age (n = 432) in the Helsinki AVM database. The cohort was further specified to include only patients with ruptured AVMs who were under 20 years of age at the time of diagnosis (n = 55). Educational level was compared to the age-matched general population of Finland. The mean 15D scores were calculated for independent variables (Spetzler-Ponce classification, admission age, symptomatic epilepsy, multiple bleeding episodes) and tested using the independent samples t-test or ANCOVA. Linear regression was used to create a multivariate model. Bonferroni correction was used with multiple comparisons.

RESULTS: The mean follow-up time from diagnosis to survey was 24.2 (SD 14.7) years. The difference in the mean 15D scores between SPC grades did not reach statistical significance. The youngest age group (< 10 years at the time of diagnosis) did less well on the dimension of usual activities than the older patients. Multiple hemorrhages significantly reduced the scores on three dimensions: mobility, speech, and sexual activity. In the regression model, symptomatic epilepsy was the only significant predictor for a lower 15D score. The educational level of the cohort was for the most part comparable to that of the general population in the same age group. AVM was the reason for early retirement in 11% of the patients, while lowered performance because of the AVM was reported by 37% of the patients.

CONCLUSIONS: Patients with ruptured AVM treated in childhood can live an independent and meaningful life, even in the case of the highest-grade lesions. Symptomatic epilepsy significantly reduced the long-term HRQoL, highlighting the need for continuing support in these patients.

Keywords: Arteriovenous malformation, AVM, Hemorrhage, Pediatric, Health-related quality of life, Educational level

FL-026

Moya-Moya disease

Surgical Revascularizations for Pediatric Moyamoya: A Systematic Review, Meta-Analysis and Meta-Regression Analysis

Keng Siang Lee^1,2, John JY Zhang³, Sanjay Bhate^2,4, Vijeya Ganesan^2,4, Dominic Thompson^1,2, Gregory James^1,2,  Adikarige Haritha Dulanka Silva^1,2

¹Department of Neurosurgery, Great Ormond Street Hospital for Childrent, London, UK

²Great Ormond Street Institute of Child Health, University College London, London, UK

³Department of Neurosurgery, National Neuroscience Institute, Singapore, Singapore

⁴Department of Paediatric Neurology, Great Ormond Street Hospital, London, UK

BACKGROUND AND AIM: There is no clear consensus regarding the technique of surgical revascularization for moyamoya disease and syndrome (MMD/MMS) in the pediatric population. Previous meta-analyses have attempted to address this gap in literature but with methodological limitations that affects the reliability of their pooled estimates. This meta-analysis aimed to report an accurate and transparent comparison between studies of indirect (IB), direct (DB) and combined bypasses (CB) in pediatric patients with MMD/MMS.

METHOD: In accordance with PRISMA guidelines, systematic searches of Medline, Embase and Cochrane Central were undertaken from database inception to 7th October 2022. Perioperative adverse events were the primary outcome measure. Secondary outcomes were rates of long-term revascularization, stroke recurrence, morbidity and mortality.

RESULTS: 37 studies reporting 2460 patients and 4432 hemispheres were included in the meta-analysis. Overall pooled mean age was 8.6 years (95%CI: 7.7;9.5), and 45.0% were male. Pooled proportions of perioperative adverse events were similar between the DB/CB and IB groups except for wound complication which was higher in the former group (RR = 2.54(95%CI: 1.82;3.55)). Proportions of post-surgical Matsushima Grade A/B revascularization favored DB/CB over IB (RR = 1.12 (95%CI 1.02;1.24)). There was no significant difference in stroke recurrence, morbidity and mortality. After meta-regression analysis, year of publication and age were significant predictors of outcomes.

CONCLUSIONS: IB, DB/CB are relatively effective and safe revascularization options for pediatric MMD/MMS. Low-quality GRADE evidence suggest that DB/CB was associated with better long-term angiographic revascularization outcomes when compared with IB, although this did not translate to long-term stroke and mortality benefits.

Keywords: Cerebrovascular accident, Hemorrhagic stroke, Ischemic stroke, Moyamoya disease, Revascularization

FL-029

Dysraphism

Ventral anchoring of the conus medullaris to prevent repeated tethering following re-untethering in spina bifida: technical note

Nobuhito Morota

Department of Neurosurgery, Kitasato University Hospital, Sagamihara, Japan

BACKGROUND AND AIM: Repeated tethering following the untethering after initial surgery for spina bifida can develop. Surgical technique to prevent repeated tethering is expected.

METHOD: Untethering after initial repair of spina bifida (SB) was performed 83 times in 72 patients during the last 20 years. Among them, 13 patients (M:F = 3:10, age: 5–37 yrs, mean: 12.2 yrs) have undergone ventral anchoring (VAnch) of the untethered conus medullares since 2014. After untethering and myeloplasty of the conus medullaris, the termina end was fixed to the ventral dura loosely using 8–0 thread. Results of VAnch was analyzed retrospectively.

RESULTS: Original SB was MMC in 7, spinal lipoma 5 and one limited dorsal myeloschisis. VAnch was performed at the 1st re-untethering surgery in 11, 2nd in 1 and 3rd in 1. Duration from the previous surgery to VAnch ranged from 1 to 23 years (average 9.2 years) and follow-up period was 4 to 96 months (average 40.4 months). All but one showed improved preoperative symptoms and no complication relating the VAnch procedure was observed. Postoperative MRI showed restored dorsal subarachnoid space in 12 patients, but the space became obscure in the follow-up MRI in 2. No patients have experienced recurrence of tethered cord syndrome after VAnch for the present.

CONCLUSIONS: VAnch was effective to restore the dorsal subarachnoid space after untethering the conus medullaris. This preliminary study suggests that VAnch seems a promising procedure to prevent re-tethering after untethering the spinal cord in SB children.

Keywords: Re-tethering, Untethering, Tethered cord syndrome, Spina bifida, Conus medullaris

FL-030

Innovation and technology

One hundred cases of spinal lipoma: Surgical procedure with Ultrasonic bone curette and High frequency bipolar forceps

Akira Gomi¹, Hirofumi Oguma², Taku Uchiyama²

¹Department of Pediatric Neurosurgery, Jichi Children's Medical Center Tochigi, Jichi Medical University, Tochigi, Japan

²Department of Neurosurgery, Jichi Medical University, Tochigi, Japan

BACKGROUND AND AIM: The purpose of spinal lipoma surgery is to prevent worsening of symptoms. Therefore, it is required to be less invasive, have no complications, and provide good long-term results. Here, we introduce our surgical procedures and results.

METHOD: A retrospective study of 100 cases of spinal cord lipoma (51 cases of conus lipoma and 49 cases of filar lipoma) who underwent initial surgery at our institute from 2006 to 2021. Surgical indications were all cases of conus lipoma, and filar lipomas that were symptomatic or had low-set conus or spinal cord abnormalities.

Surgical procedure) We introduced ultrasonic osteotomy SONOPET® in 2007, partial laminectomy by longitudinal-torsional vibration tip was performed for filar lipomas. Since 2011, laminotomy for conus lipomas was performed with scalpel- type tip, and the spinous process was fixed by suturing with the supraspinous ligament and paraspinal fascia. Since 2012, lipomas of conus have been removed using the high-frequency bipolar VESALIUS® according to the method of Pang et al.

RESULTS: Hemilaminectomy by SONOPET could be performed even in older children, and had no complication. It has the advantage of preserving the vertebral arch and posterior supporting tissue. SONOPET laminotomy and reconstruction are considered to be less invasive than laminectomy in that they can preserve supporting tissue. No patients had spinal deformities and the long-term results were good. VESALIUS is capable of incision and coagulation without heat diffusion, which is particularly useful for the dorsal type to confirm the white plane while avoiding spinal cord injury. Determining the cut surface with the transitional type or caudal type remains an issue.

CONCLUSIONS: Our surgical procedure was considered to be useful in terms of invasiveness and long-term results. We would like to continue to develop it in the future.

Keywords: Spinal lipoma, Surgery, Ultrasonic bone curette, High frequency bipolar forceps

FL-031

Occult tethered cord

Urological outcome following surgery for primary tethered cord syndrome

Navneet Singla

Department of Neurosurgery, PGIMER, Chandigarh

BACKGROUND AND AIM: Primary Tethered Cord Syndrome (TCS) is a congenital disorder due to defect in central neurulation and usually presents with pain, sensory and motor deficits, urological symptoms, foot deformities, scoliosis, cutaneous stigmata. The main aim of surgical detethering is to release the tethering structure and the chronic tension on the cord. Urological recovery and good outcome depends upon pre-operative deficits and timing of surgery.The Main objective of this study is to analyze the urological outcome at 6 months post-operative period after detethering for Primary TCS and its association with type of anomaly.

METHOD: A total of 48 patients of Primary TCS with age ranging from 2 to 12 years were taken. They were assessed with pre-operative symptoms, USG KUB and urodynamic study (UDS) and then re assessed at 6 month post-operative.

RESULTS: Out of 48 patients, 26 (54%) had pre operative urological symptoms. 38 patients showed abnormal UDS. 29 (60%) patients had improvement in UDS score while 17% showed worsening of UDS score. Younger patients and patients having pre operative urological symptoms improved more. Patients with LMMC having Neural Placode did not show significant benefit.

CONCLUSIONS: Early age of presentation and patients without Neural placode show better urological outcome. Urodynamic studies should be considered as one of the first line investigation in evaluation of patients of TCS.

Keywords: Tethered cord syndrome, Urodynamic study

FL-032

Occult tethered cord

Normal to abnormal: Reappraisal of Significant Event criteria. Deduction from electrophysiological correlation in 264 cases of Intraoperative monitoring for surgery for the tethered cord

Suhas Udayakumaran¹, Sneha R Ramakrishnan²

¹Division of paediatric Neurosurgery, Department of Neurosurgery, Amrita Institute of Medical Sciences and Research Centre, Kochi, India

²Division of Neurophysiology, Department of Neurology, Amrita Institute of Medical Sciences and Research Centre, Kochi, India

BACKGROUND AND AIM: The current recommendations for warning criteria during intraoperative neuromonitoring (IONM) are largely empirically derived. It remains challenging to define the parameters to keep it adequately sensitive to intraoperative neurophysiologic monitoring. Moreover, the present set of alarm criteria is a comparison with a baseline that can be abnormal by itself.

In this work, we identify the age-specific normative baseline of IONM and based on this, we try to clarify the significant event criteria.

METHOD: This is a prospective and retrospective study performed at the Amrita Institute of Medical Sciences and Research Centre, Kochi, India. We collected data from consecutive patients, under the age group 15 years who underwent surgery for tethered cord, under IONM, during the study period of March 2011 to July 2021.

RESULTS: We had a total of 39 events (n = 264 patients), operated for tethered cord, 117 muscles are involved in the event, out of which 12 muscle MEP (n = 4) 10.25% had deterioration and 105 muscle MEP (n = 35) 89.75% had improvement. In cases of improvement, amplitude increased by 40–100%, latency reduced by 40–100%, and duration increased by 70–100%. In the case of deterioration when compared to the baseline of that patient's amplitude is reduced by 20–60%, latency increases by 70–100%, and duration is reduced by 40–80%. With our alert criteria, we had a positive predictive value of 88.2% and a negative predictive value of 97.1%.

CONCLUSIONS: We conclude that any significant change (as defined) in amplitude, latency, and duration in comparison with the patient-specific baseline vis-à-vis the age-specific normative baseline is important. Changes in these parameters are simultaneous, hence, the amplitude is a convenient reasonable change as it can be easily identified and monitored. Keeping the low threshold of change for warning criteria is probably important for early or complete recovery.

Keywords: Tethered cord syndrome, Intraoperative neuromonitoring, Outcome, Spinal dysraphism

FL-033

Antenatal diagnosis and treatment

Histological study of the removed membranous area in fetal myelomeningocele repair: implications for dermoid cyst prevention

Frank Van Calenbergh¹, Raf Sciot², Philippe De Vloo¹, Jan Deprest³

¹Department of Neurosurgery, University Hospitals, Leuven, Belgium

²Department of Pathology (Neuropathology), University Hospitals, Leuven, Belgium

³Department of Obstetrics and Gynaecology, University Hospitals, Leuven, Belgium and Research Department of Maternal Fetal Medicine, UCL Institute for Women’s Health, University College London, U.K

BACKGROUND AND AIM: After fetal myelomeningocele (MMC) repair, several authors have noticed the occurrence of later spinal cord tethering caused by inclusion dermoid cysts, possibly more frequent than after postnatal MMC closure. This is probably caused by incomplete removal of epithelial remnants when releasing the neural placode from the skin by cutting the membranous area, considered to be of arachnoid origin. After having encountered 3 cases of postnatal dermoid cysts in our fetal neurosurgery program, we decided to perform a histological examination of the removed membrane fragments in the later patients.

METHOD: The standard technique consists of an incision at the border between skin and area membranosa, followed by removal of these membranes as close to the placode edge as possible. In 24 cases of fetal MMC repair (November 2020—May 2022), this membranous area was examined using staining for prekeratin (epidermis), EMA (meningothelial cells) and GFAP (glial tissue).

RESULTS: In all but 2 cases, immature cells were seen in the tissue. Ten cases consisted of only immature skin, 12 cases contained skin elements mixed with either glial (5), meningothelial (2) cells or both (5). There was no statistical relationship with the morphological type (flat ‘myeloschizis’ type or raised sac ‘myelomeningocele’). However, the 2 cases without skin cells were of the myeloschizis type. As yet no dermoid cyst has been seen in these recent cases.

CONCLUSIONS: In the membranous area between the neural placode and the readily identifiable skin border, skin cells are usually present. Therefore, meticulous neurosurgical technique is required to remove these thin membranes, not limiting the removal to tissue that “looks epidermal” but cutting the thin membranes as close as safely possible at the border of the placode.

Keywords: Fetal repair, Myelomeningocele, Dermoid cyst

FL-034

Dysraphism

Effectiveness of onlay dural implants in prevention of CSF leak and wound breakdown in paediatric spinal dysraphism surgery: A single centre experience

Azam Ali Baig, Fardad T Afshari, Wai C Soon, William B Lo, Richard A Walsh, Desiderio A Rodrigues, Guirish A Solanki

Department of Neurosurgery, Birmingham Women's and Children's Hospital, Birmingham, United Kingdom

BACKGROUND AND AIM: To report and compare the efficacy of DuraGen and Duraform onlay dural implant usage in dysraphism surgery.

METHOD: A 13-year retrospective review of all paediatric spinal dysraphism surgeries from the surgical database and operative implant logbooks was conducted. 439 patients underwent surgical correction for all spinal dysraphisms from 2006–2019. The types of dural implants used were confirmed through the operative implant logbooks. The incidence of post-operative CSF leak and/or wound breakdowns requiring re-exploration were identified through the operative database. Reasons for reoperations were explored. 3 groups (duragen, duraform, no dural substitute) are evaluated.

RESULTS: 439 children underwent dysraphic repair procedures. 392 had onlay dural implants and 47 did not. All primary leaking Myelomeningocoele repairs were performed within 48 h of birth. DuraGen was used in 270/392 (69%). Duraform in 122/392 (31%). DuraGen had 4 (1.5%) and Duraform had 18 (14.8%) reoperations. The reoperations in the Duragen group were due to 1(0.37%) CSF leak and 3 (1.1%) wound-breakdowns. The CSF leak in the duraform group was 9% but accounted for 61% (11/18) of reoperations. Wound dehiscence was 5.7% (7/18). In the non-onlay dural group, the CSF leak was 4.3% (2) and 30% (14) had wound-breakdowns. The relative risk for CSF Leak in the non-onlay group versus duragen is 11.48. The relative risk ratio of wound breakdown in the non-onlay versus onlay implant is 11.7, and this rises to 26.8 if compared with duragen alone.

CONCLUSIONS: The use of onlay dural implants to achieve dural closure that prevents CSF leak is safe and effective. Duragen was particularly effective and associated with significantly fewer complications requiring revision surgery compared to Duraform. Repairs without use of onlay dural substitutes compared with duragen were 11.5 times more likely to have a CSF leak and 26.8 times more likely to have a wound-breakdown.

Keywords: Dural graft, Pediatrics, Spinal dysraphism

FL-035

Dysraphism

Diagnosis, clinical presentations, and outcome determinants of surgically treated children with neural- tube defect: A prospective cohort study in a high-volume centre

Abenezer Tirsit Aklilu¹, Yemisirach Bizune Aklilu¹, Bethelehem Yesehak Worku¹, Mahlet Yigaramu Gebremariam³, Asrat Demetse A.⁴, Filmon Mengesha A.⁵, Samuel Masresha Fetene¹, Eyob Zenebe Wondemagawu¹, Samuel Getahun E.¹, Tsegazeab Laeke Teklemariam¹, Bente E. Moen⁶, Morten Lund Johansen², Ruby Mahesparan Rupavathana²

¹Division of Neurosurgery, Addis Ababa University, Addis Ababa, Ethiopia

²Department of Neurosurgery, university of Bergen, Bergen,Norway

³Department of Gyobs, Addis Ababa University, Addis Ababa, Ethiopia

⁴Department of paediatrics, Addis Ababa University, Addis Ababa, Ethiopia

⁵Department of psychiatry, Addis Ababa University, Addis Ababa, Ethiopia

⁶Department of Global Public Health and Primary Care, University of Bergen, Norway

BACKGROUND AND AIM: Neural tube defects (NTDs) are developmental malformations caused by defects in neurulation or modifications in neural tissue morphogenesis. Treatment and prevention of various complications associated with NTDs require multidisciplinary care. Surgery is usually the first line of treatment.

METHOD: We prospectively investigated all children surgically treated for NTD closure from April 2019 to May 2020 at the paediatric neurosurgical specialty centre in Addis Ababa, Ethiopia, over a period from the primary admission until one year. We investigated outcomes in-hospital and at follow-up, and analyzed predictors of complications and mortality. The outcomes were compared with those of a recently published retrospective study from the same centre.

RESULTS: A total of 228 children were included. The mean age at presentation was 11 days (median 4, (1–105)). The commonest anatomical location of defects was the lumbar (57%). Half of the children (49%) had paraplegia in their lower extremities. During a one-year follow-up of 143 (62.7%) children, 123 (83%) were alive. Hydrocephalus (P = 0.05) and younger age (P = 0.02) were identified as risk factors for mortality. The wound-related complication rate was 55% at one year and was associated with large defects (mean, 162.9 mm³ & P = 0.04), intraoperative blood loss (mean 50.42 ml & P = 0.02), and late presentation to the hospital (mean age 13 days & P = 0.01). The readmission and reoperation rates were 40 and 20% and associated with hydrocephalus and open defects; 80% of the re-admissions were related to hydrocephalus treatment (P = 0.04) and 87% of the re-operated children had an open defect (P = 0.05). When comparing with a recently published retrospective study from the same institution, we found a significant improvement in outcomes.

CONCLUSIONS: NTD closure is a very common procedure in Addis Ababa. Overall survival after surgery is acceptable, but one-year mortality, complication, and re-admission rates were still high.

Keywords: Neural tube defect, Outcome, Low-income country, Ethiopia

FL-036

Dysraphism

Social, Psychological, and Economic Burdens Experienced by People with Spina Bifida and Their Caregivers: Review of 50 cases from a developing country

Mansur Idris Muhammad¹, Salman Ayodeji Yusuf¹, Nasiru Jinjiri Ismail², Ali Lasseini², Aliyu Muhammad Koko², Muktar Isah Teli¹, Bello Bala Shehu²

¹Division of Neurological Surgery, Department of Surgery National Hospital Abuja Nigeria

²Regional Center for Neurosurgery, Usmanu Danfodio University Teaching Hospital Sokoto Nigeria

BACKGROUND AND AIM: Areas of peoples’ lives affected by Spinal Bifida (SB) included physical and role functioning, activities of daily living, bodily pain, vitality, emotional functioning, mental health, self-esteem, self-image, social functioning, relationships, and sexual functioning. Areas of caregivers’ lives affected included activities of daily living, work impact, time consumption, parental responsibilities (including responsibilities to other children), confidence, feelings and emotions, mental health, stress, social impact, psychological adjustment, relationships (with SB child, siblings, other family members), social support, coping strategies, and termination decisions. Cost burdens on patients and caregivers also include out-of-pocket costs, lost wages, or household production due to increased morbidity and mortality, transportation and other nonmedical costs.

METHOD: Review of case and follow-up notes with telephone conversations of all patients who presented and had repaired of spinal bifida between March 2017 to March 2022 (Five years) at the Regional Center for Neurosurgery, Usmanu Danfodio University Sokoto (UDUTH) and National Hospital, Abuja (NHA) Nigeria were carried out.

RESULTS: Myelomeningocele associated with skeletal deformity and bi-sphincteric dysfunctions constituted 60% (30 cases) of the reviewed cases, with a male to female ratio of 1:2. Only 8 patients (4%) are covered by health insurance. Parental work absenteeism or drop out especially by working mothers is alarming. Majority of the parent required psychological counselling. Very few parents (11%) wish to carry another pregnancy again. They described societal stigmatization as a fundamental encumbrance.

CONCLUSIONS: This review highlights the need to provide care and support to individuals with SB and their caregivers. Results also emphasize the importance of effective long-term public health campaigns and/or newer strategies to prevent NTDs, such as SB.

Keywords: Spinal bifida, Psychological, Social, Economic, Myelomeningocele

FL-037

Dysraphism

Lessons Learnt In Retethered Spinal Cords in Dysraphism- experience of 20 years

Sandip Chatterjee

Dept of Neurosurgery, Park Clinic, Kolkata, India

BACKGROUND AND AIM: Was to retrospectively review our series of surgery for SYMPTOMATIC retethering in spinal dysraphism performed in children and young adults up to the age of 30 years over a 20 year period from 2001 to 2020. This was done to try and identify a)Causes of retethering and how to prevent the same, and b)To try and devise a classification system of cases of retethering.

METHOD: 66 cases of retethering were identified over this period. Of these 28 were following repair of open neural tube defects, 26 following repair of lipomas, and 12 were following surgery for other conditions. Intentionally no distinction was made between primary surgery performed by the author and surgery performed elsewhere.

The age of patients of retethering ranged from 3 to 30 years, and the presentation occurred from 2 to 30 years after the first surgery.

RESULTS: We were able to classify retethering into Type 1 or early when this occurred within 2 years of the first surgery, and which we termed “Early retethering” and Type 2 or “Late retethering” which occurred more than 2 years after the first surgery. In each case an attempt was made to try and determine the exact cause of retethering.

CONCLUSIONS: We were able to conclude that Type 1 retethering is a fault of surgical technique- Failure to recognize the tethering elements, improper dural closure, failure to remove adequate abnormal tissue; whereas Type2 retethering was caused by growth spurt, increase in weight, Chiari malformation, trauma or even a congenital narrow spinal canal.

It was also established that using intraoperative neuromonitoring was an important adjunct to prevent retethering.

Keywords: Retethering dysraphism

FL-038

Dysraphism

Association of Jarcho-Levin Syndrome with Spina Bifida in Children: Its Prevalance and Urological Outcome in a Cohort of 837 Patients

Seyhmus Kerem Ozel¹, Ibrahim Alatas², Doga Ugurlar³, Revna Cetiner³, Nafiye Sanlier³, Teoman Karakurt³

¹Goztepe Training and Research Hospital, Istanbul, Turkey

²Baskent University Hospital, Istanbul, Turkey

³Istanbul Training and Research Hospital, Istanbul, Turkey

BACKGROUND AND AIM: Jarcho Levin Syndrome (JLS) is diagnosed when vertebral and costal anomalies are associated with prominent short stature and kyphoscoliosis. The aim of this study was to delineate the clinical features and prevalence when JLS is observed with spina bifida.

METHOD: Patients who were treated in our Spina Bifida Center were enrolled retrospectively. Patients who had the diagnosis of JLS and spina bifida (SB) and only SB were compared. Age, gender, urinary tract infection (UTI), clean intermittent catheterization (CIC), constipation, anticholinergic usage, presence of hydronephrosis, renal scarring, vesicoureteral reflux, bladder wall thickness, bladder capacity, compliance, detrusor activity, sphincter activity and residual urine were compared with student’s t test and chi square test.

RESULTS: A total 60 patients (7,17%) were diagnosed as JLS among 837 SB patients. Patients with JLS were compared with the rest of 777 SB patients. The diagnosis was SB aperta in 78,3% of JLS and 68% of SB patients (p = 0,099). UTI was present in 42,9% of JLS patients and 45,3% of SB patients (p < 0,0001). CIC was necessary in 31,6% of JLS patients and 40,4% in SB patients (p < 0,0001), anticholinergic was used in 25,9% of JLS patients and 32,2% in SB patients (p = 0,027). Constipation was present in 38,6% of JLS patients and 43,9% of SB patients (p = 0,003).

CONCLUSIONS: More need for CIC, more frequent anticholinergic usage, decreased compliance, more underactive detrusor and detrusor sphincter dyssynergia in SB may show that bladder is more affected in SB than JLS. General prevalence of JLS in SB is 7,17% in this cohort. Patients should be carefully evaluated clinically and urodynamically to justify proper treatment indications in these patients.

Keywords: Jarcho-levin syndrome, Spina bifida, Urodynamics

FL-039

Dysraphism

Management of hydrocephalus associated with myelomeningocele: Can we efficiently reduce the rate of the shunt?

Nabila Tighilt, Nazim Boumahdi, Farid Bouchenaki, Souad Bakhti

Pediatric Neurosurgery Unit, Ali Ait Idir Hospital, Faculty of medicine, University of Algiers1, Algiers, Algeria

BACKGROUND AND AIM: Myelomeningocele is the most serious and complex birth defect affecting the CNS compatible with life. The shunt rate of associated hydrocephalus reached 80%, but the complications of the shunt constitute an additional morbidity. Nowadays, many neurosurgeons seek to reduce the shunting rate in order to decrease morbidity.

METHOD: We report a retrospective series of 100 cases of myelomeningocele. All the patients were operated on for myelomeningocele, except one patient who presented with laryngeal stridor. In our series, treatment of hydrocephalus was motivated by progressive macrocrania in 59 cases, inspiratory stridor in 4 cases, poor sucking in 3 cases, motor deficit in 1 case and a postoperative fistula in 5 cases.

RESULTS: Shunt was performed postoperatively in all patients, except for the patient who presented with severe brainstem dysfunction, that requires ventricular drainage as a first step in emergency. In our series, 33 patients did not require treatment of hydrocephalus. Indications for treatment of hydrocephalus in myelomeningocele are progressive macrocrania and brainstem dysfunction. The heavy morbidity associated with the shunt will be responsible of poor quality of life. This has resulted in the current trend which is in favor of a more tolerant management of hydrocephalus and a reduction in the shunt rate which has reached 51.9 to 40% depending on the series. In our series, treatment for hydrocephalus is still high at 67%, but selection bias impacted our results.

CONCLUSIONS: Indications for the treatment of hydrocephalus are well defined and are limited to evolutive intracranial hypertension signs and brainstem dysfunction. Ventricular dilatation and CSF leak are not valuable indications for ventricular drainage. Monitoring criteria allowed us to tolerate a certain increase in the size of the ventricles. This attitude will lead to a reduction in the rate of the shunt in children with myelomeningocele and thus reduce the morbidity linked to the shunt.

Keywords: Myelomeningocele, Hydrocephalus, Ventricular diversion, Macrocrania, Brainstem dysfunction

FL-040

Spine

Operated spinal lipomas: single centre experience

Ahmed Aly¹, Libby Van Tonder², Helen Fiona Mcandrew³, Dawn Hennigan², Benjamin J. Hall², Benedetta Pettorini²

¹Department of Neurosurgery, Royal Stoke Hospital, Stoke, UK

²Department of Neurosurgery, Alder Hey Children's Hospital NHS Foundation Trust, Liverpool, UK

³Department of Urology, Alder Hey Children's Hospital NHS Foundation Trust, Liverpool, UK

BACKGROUND AND AIM: The role of surgery in managing lumbosacral lipomas is controversial, with little standardization in practice. We aim to demonstrate our single center experience in the surgical management of lumbosacral lipomas, by applying recently suggested criteria for low-risk lesions and comparing outcomes.

METHOD: Operated lipoma patients between 2012 and 2017 were extracted from a prospective data base. Pre- and post-operative clinical data were collected and analyzed. A subcategory of patients with MRI findings compatible with recently suggested ‘Thompson criteria’ were identified. Outcome measures included were also compared between this subcategory and the general cohort.

RESULTS: 13 patients diagnosed with spinal lipoma underwent operative management during this time. 6 patients reported pre-operative urological dysfunction, of whom 1 worsened postoperatively and one improved. Another patient developed urological complications postoperatively. 7 patients reported preoperative neurological deficits, 3 of whom improved post-operatively. No patient developed a new neurological deficit postoperatively. One patient had total resection of their lipoma, 9 had subtotal or near total resection and 3 had partial resection. No major difference in outcome between low-risk and high-risk lesions according to Thompson criteria were identified in our cohort.

CONCLUSIONS: Surgical resection of lumbosacral lipomas is feasible and safe; proving effective in those achieving total resection. We hope in the future a more profound understanding of natural history and more developed classification criteria will help in counselling and managing patients more safely and predictably.

Keywords: Spinal, Lipoma, Operative, Paediatric

FL-041

Dysraphism

Fetoscopic repair of open neural tube defects: a case series of 16 patients who underwent fully percutaneous or open fetoscopic repairs

David Rowland¹, Ladina Greuter¹, Susan Mash³, Claire Cairns¹, Anca Vasilica⁴, Chula Goonasekera², Sarah Nour², Matthew Brown³, Marta Santorum Perez³, Kypros Nicolaides³, Cristina Bleil¹, Bassel Zebian¹

¹Department of Paediatric and Adult Neurosurgery, King’s College Hospital NHS Foundation Trust, London, UK

²Department of Anaesthesia, King’s College Hospital NHS Foundation Trust, London, UK

³Fetal Medicine Unit, King’s College Hospital NHS Foundation Trust, London, UK

⁴University College London Medical School, London, UK

BACKGROUND AND AIM: Myelomeningocele is a significant cause of morbidity world-wide; it affects 33–48 per 100,000 live births. Antenatal repair is gaining in popularity driven by the MOMS trial. Open fetal repair is associated with maternal complications. There is an increased drive towards more minimally invasive / fetoscopic procedures with an increasing number of centres performing these. We report the UK’s first experience of fetoscopic repairs (fully percutaneous and open fetoscopic).

METHOD: Retrospective case series.

RESULTS: 16 fetuses underwent repair at KCH using materno-fetal anaesthesia between September 2018 and May 2022. They were diagnosed on routine antenatal ultrasound scans and had subsequent fetal MRI. They fulfilled the eligibility criteria and informed consent was obtained after discussion of all the available options. We initially performed fully percutaneous fetoscopic closure for all patients then elected to exteriorise the uterus for patients with a completely anterior placenta to allow port insertion. Two weekly assessments were performed, and fetal MRI scan planned 4 weeks postoperatively. We report the maternal and fetal outcomes and compare with the published literature.

CONCLUSIONS: Fetoscopic myelomeningocele repair has already been shown to be a valuable addition to the armamentarium for repair of open spinal neural tube defects. The evidence so far suggests there is reduction in the risk to mothers and subsequent pregnancies and much work has taken place to reduce the rates of premature delivery and improve fetal/neonatal outcomes.

Keywords: Myelomeningocele, Open neural tube defects, Dysraphism, Fetoscopy

FL-042

Dysraphism

Multidisciplinary approach for the treatment and management of lipomyelomeningoceles: a single centre experience with long-term surgical, neurological and urological outcomes

Benjamin James Hall¹, Maria Rosaria Scala², Raenette David¹, Helen Fiona Mcandrew¹, Benedetta Pettorini¹

¹Department of Neurosurgery, Alder Hey Children's NHS Foundation Trust, Liverpool, UK

²Department of Neurosciences and Reproductive and Odontostomatological Sciences, Division of Neurosurgery, University of Napoli Federico II, Naples, Italy

BACKGROUND AND AIM: Lipomyelomeningoceles (LMMC) are a form of spina bifida occulta, composed of a subcutaneous lipomas connected to the spinal cord through a midline defect in the lumbosacral fascia Prophylactic surgery in LMMC is debated, therefore, we present ten years of operatively managed LMMC at our centre.

METHOD: Electronic case notes of all patients diagnosed with LMMC between January 2012 and May 2022 were retrospectively reviewed. Data collection included: sex, age, indication for surgery, pre- and postoperative urological status (catheterisation, urinary tract infections, urodynamics), pre- and postoperative neurological status (weakness, deformity) and complications.

RESULTS: Of the twenty-three (23) patients included, the median age at surgery was 8.8 months (range: 1 month—12 years). 69.5% of patients were female with five patients diagnosed antenatally, sixteen at birth and the remainder later in childhood. 91% of patients presented with lumbosacral fatty lumps; three patients were also diagnosed with Chiari malformations. Prophylactic surgery was undertaken in 73.9% (17) of cases, with the remainder performed for urological or neurological decline.

Regarding urological function, 34.8% demonstrated abnormal preoperative parameters and 60.9% (14) underwent preoperative urodynamics. Of these, 30.4% showed clinical improvement while all other patients remained stable. Of all patients who presented with neurological impairment (30.4%), three patients (42.9%) improved neurologically: two of whom had motor improvement and one a reduction in pain.

There were three (3) complications encountered – one cerebrospinal fluid leak, one wound dehiscence and one superficial wound site infection. Mean follow-up was 33.5 months from surgery, during which time no patients required further surgery for their LMMC.

CONCLUSIONS: Operative management for LMMC remains controversial, particularly in the context of prophylactic surgery. A multi-disciplinary approach to surgical management of LMMC is paramount to achieving good results. Our series demonstrates surgery, in select patients, can positively impact on both urological and neurological function.

Keywords: Lipomyelomeningocele, Prophylactic, Spinal, Dysraphism, Urodynamics

FL-043

Dysraphism

Surgical Outcomes of Myelomeningocele Repair: a 20-Year Experience from a Single Center in a Middle-Income Country

Mohammad Sadegh Masoudi, Sina Zoghi, Maryam Feili, Mohammad Amin Mosayebi, Mohammad Amin Afifi, Afrooz Feili, Reza Taheri

Shiraz university of medical sciences, school of medicine, neurosurgery department

BACKGROUND AND AIM: Background.

Spina bifida is the second major cause of congenital disorders following congenital heart defects and the most common central nervous system malformation compatible with life, which primarily affects populations of low socioeconomic status.

OBJECTIVE: To describe the outcome of myelomeningocele surgical management and predictors of its postoperative complications and mortality.

METHOD: This retrospective chart review studies the children who underwent surgical management for myelomeningocele in our institution from May 2001 to September 2020.

RESULTS: 256 patients were enrolled. The median age at the operation was roughly eight days (IQR: 7). The most common site of involvement of Myelomeningocele (MMC) was Lumbosacral (86%, n = 204). At the evaluation conducted prior to operation, CSF leaking was observed in 7% (n = 16) of the patients. Postoperatively, 5.7% of the patients were expired in the 30 days following the operation (n = 14), while 24% needed readmission (n = 47). The most common complications leading to readmission included wound dehiscence (n = 10, 42%) and wound purulence (n = 6, 25%). No variable was significantly associated with postoperative complication except for the site of the lesion (p-value = 0.035) and the presence of the lipid content in the defect (p-value = 0.044).

CONCLUSIONS: The presence of lipid compartment in the lesion and the site of the lesion are the two factors that were associated with the rate of mortality. However, further investigations into preoperative interventions and risk factors to mitigate the risk of complications and mortality are highly encouraged.

Keywords: Myelomeningocele, MMC, Neural tube defect, Spina bifida, Surgical outcome, Pediatric neurosurgery

FL-044

Spine

CSF leak after intradural spinal surgery in the pediatric population

Emma M.H. Slot¹, Tristan P.C. van Doormaal², Kirsten van Baarsen³, Menno R. Germans⁴, Nick Krayenbühl⁴, Luca Regli⁴, Eelco W. Hoving⁵

¹Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands

²Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands; Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland

³Department of Neuro-oncology, Princess Maxima Center for Paediatric Oncology, Utrecht, the Netherlands

⁴Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland.

⁵Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht; Department of Neuro-oncology, Princess Maxima Center for Paediatric Oncology, Utrecht, the Netherlands

BACKGROUND AND AIM: Cerebrospinal fluid leakage is a potentially serious complication after intradural spinal surgery. This study aims to establish the incidence of CSF leakage and associated complications after intradural spinal surgery and describe the treatment strategies applied.

METHOD: All patients aged 18 years or younger who underwent intradural spinal surgery between 2015 and 2021 in three tertiary neurosurgical referral centers with complete follow up to at least 6 weeks and a complete surgical report were retrospectively reviewed. The primary outcome measure was CSF leakage within 6 weeks after surgery, defined as leakage of CSF through the skin. Secondary outcome measures included: presence of pseudomeningocele (PMC), meningitis and surgical site infection (SSI).

RESULTS: We identified 80 procedures, representing 68 individual patients. The most frequent indication was tumor resection (n = 43), followed by spina bifida correction (n = 35) and vascular surgery (n = 2). The mean age was 6.3 (SD 6.2) years. CSF leakage occurred in 2.5% (2/80) of cases. These leakages occurred at day 3 and 21 after the index procedure. One patient was treated with pressure bandage and an external lumbar drain on day 3 after diagnosis of the leak, the other was treated with wound revision surgery on day 1 after diagnosis of the leak. Three patients developed a PMC (3.8%). There was one case of PMC without a CSF fistula, which was treated with wound revision surgery. SSI occurred in 11.3%, including both cases of CSF leak. There were no cases of meningitis.

CONCLUSIONS: CSF leakage after intradural spinal surgery in a pediatric population is relatively rare (2.5%). Nevertheless, the clinical consequences with respect to secondary complications such as infection and necessity for invasive treatment are serious. Development of preventative strategies for spinal surgery in the pediatric population is mandatory.

Keywords: Cerebrospinal fluid leakage, Pediatrics, Infection, Spinal surgery, Spina bifida

FL-045

Spine

Surgical management of different types mucopolysaccharidosis -related orthopedics pathology

Polina Ochirova

Federal State Budgetary Institution "National Ilizarov Medical Research Centre for Traumatology and Ortopaedics" Ministry Healthcare, Russian Federation

BACKGROUND AND AIM: Spinal pathology in patients with mucopolysaccharidosis a problem requiring early treatment.

METHOD: We analyzed 15 cases of mucopolysaccharidosis (MPS), treated in Ilizarov Center in 2012 – 2022. There were 1 patient with MPS IH-type, 2 patient with MPS IHS-type, 8 patients with IVA-type and 4 patients with MPS type VI. The age of the patients ranged from 2,5 to 26 years-old. All patients had spinal deformity with primary and/or secondary stenosis of the spinal canal. Various surgical treatments were used: 1) two staged surgery was perfomed in one patient with cervical myelopathy and scoliosis: C0-C7 decompression with occipitospondylodesis (OSD) firstly and dual growing rod construction secondly; 2) final fusion in 2 patients with scoliosis; 3) decompression at the stenosis level (cervical spine) with OSD in 12 patients with cervical myelopathy.

RESULTS: Scoliosis value was from 20° to 65° Cobb, kyphosis from 15° to 80° Cobb. Four patients had vertebral stenosis and myelopathy (Frankel C). All patients had pulmonary and cardiac dysfunctions: vital capacity of the lungs was from 21 to 50% and abnormal ECG. Imbalance in the frontal and sagittal planes was present in 60% of patients. Through surgical treatment correction of the kyphosis was by 68% and scoliosis by 85%. In 4 (50%) patients with spinal stenosis neurologic status improved to Frankel E.

CONCLUSIONS: Patients with MPS quite often have vertebral stenosis and myelopathy, in such patients with combined stenosis of the spinal canal, it is necessary to combine decompression and fusion.

Keywords: Mucopolysaccharidosis, Spinal deformity, Scoliosis, Stenosis, Cervical myelopathy, Decompression

FL-046

Spine

Outcome Analysis of Surgical Management of Paediatric Cervical Kyphotic Deformity (CKD): an Institutional Experience

Sivaraman Kumarasamy, Pankaj Kumar Singh, Dattaraj P. Sawarkar, Rajinder Kumar, P. Sarat Chandra, Shashank Sharad Kale

Department of Neurosurgery, Neurosciences Centre, All India Institute of Medical Sciences, New Delhi, India

BACKGROUND AND AIM: Paediatric cervical kyphotic deformity (CKD) is extremely rare and occurs due to congenital, traumatic, metabolic or neoplastic processes which mandates surgical correction. Most outcomes analysis following surgery are small retrospective case series and are limited to specific etiology or surgical technique. The objective of our study is to analyse a single-centre operated paediatric CKD, highlighting (a) the clinical and radiological outcomes (b) the safety and efficacy of different surgical approaches (c) change in the quality of life in terms of neck pain, myelopathy and deformity correction.

METHOD: Patients (aged ≤ 18 years) operated at a tertiary centre between January 2009 to April 2022 were included. Besides demographic details, the outcome measures assessed were clinical (Nurick grading, mJOA score), radiological (Cobb’s angle) and operative complications.

RESULTS: A total of twenty-two patients were included, with mean age of 12.90 ± 4.02 years (3 – 18) of which ten were syndromic, three were metabolic, seven were post-traumatic and one post-infective. Thirteen patient had features of myelopathy on presentation. All underwent surgical correction, of which nine patients underwent Antero-posterior approach, eight patients underwent Posterior only approach and four patients underwent Anterior only approach. Clinically, patients improved postoperatively with – Nurick grade (pre vs. post: 3.24 vs. 2.24, p – 0.172), mJOA score (pre vs. post: 10.19 vs. 12.71, p – 0.679). There was significant deformity correction from 37.086° to 13.725° (p – 0.045). Mean blood loss encountered was 680 ± 671.93 cc. Early complications included intraoperative hemodynamic instability (4) and lung collapse (1). Late complications included junctional kyphosis (1). Mean follow-up was 49.38 ± 44.15 months.

CONCLUSIONS: Pediatric CKD are rare, debilitating condition which can be managed surgically. Antero – posterior approach provides circumferential decompression and better correction compared to Anterior only and posterior only approach. Patients should be screened for syndromic association and regularly followed.

Keywords: Cervical kyphotic deformity, Antero-posterior, Junctional kyphosis

FL-047

Spine

Congenital cervicothoracic dislocation: a rare condition with a high risk of complications

Olga M Sergeenko, Alexey V Evsyukov, Egor Yu Filatov, Sergey O Ryabykh, Alexander V Burtsev, Alexander V Gubin

Ilizarov Center

BACKGROUND AND AIM: Congenital cervicothoracic dislocations are rarely described in the literature. The exact causes of their occurrence poorly studied and treatment tactics vary. The main goal of our work was to analyze the world experience and our own experience in the treatment of congenital pediatric cervicothoracic dislocations and understand what type of treatment is optimal for these patients.

METHOD: We performed a literature review and found seven literature sources that describe congenital cervicothoracic dislocations and its treatment. In addition, we analyzed the data of five own patients.

RESULTS: Only eight patients from seven sources with congenital cervicothoracic dislocations and a description of treatment tactics were found. The treatment was long and accompanied by a large number of complications. Among five own patients four had Klippel-Feil syndrome (Figs. 1 and 2) and one had neurofibromatosis. All patients had preoperative neurological disorders. Posterior instrumental fixation with posterior vertebral body resection was performed in four cases and one patient had combined surgery. Neurological deterioration happened in two patients, neurological improvement was in two patients and one patient was stable. We have divided all complications according to the Clavien-Dindo-Sink: four patients Grade II, five Grade IIIB and one Grade IV types. The total number of surgeries related to complications was four. Average follow-up time was five years (from one to 9.8 years).

CONCLUSIONS: Congenital cervicothoracic dislocations are an extremely rare and difficult to treat pathology that manifests in early age and requires early treatment. Tactics of treatment is determined individually, but according to the literature and our own experience, early multi-stage combination treatment is preferred, although it requires more effort.

Keywords: Congenital cervical thoracic dislocation, Cervical thoracic spondyloptosis, Cervical thoracic spondylostesis, Cervocothoracic instability, Segmental spinal dysgenesis

FL-048

Spine

Traumatic rotatory subluxation of C1C2 joint -a review of 36 cases

Siddharth Dipakbhai Mistry, Sandip Subirkumar Chatterjee

Park Clinic 4 Gorky terrace,Kolkata,West Bengal, India

BACKGROUND AND AIM: To study the clinical presentation and management strategies for traumatic rotatory subluxation. Brief introduction-Traumatic rotatory subluxations are rare and may be caused by trivial trauma and may present with torticollis. They represent a rotatory deformity of the atlas on a fixed axis.

METHOD: We retrospectively reviewed all cases of rotatory C1C2 subluxations and we could identify 36 traumatic rotatory subluxation cases from January 2000 till December 2020. All these cases were thoroughly evaluated clinicoradiologically by means of CT and MRI scans.In all cases preliminary skull traction(Holter) was applied. The patients were evaluated for etiology, associated trauma, loss of consciousness, treatment undertaken, and neurological status before and after reduction.

RESULTS: The average time from trauma to treatment ranged from 3 days to 6 months(average). 19 patients had trivial trauma and presented with traumatic torticollis and only one presented after 6 months as his injury was missed due to polytrauma. The remaining 16 patients presented after falls. Only 7 out of 36 patients had any neurodeficit. In all cases CTScans of the atlantoaxial junction were done. After preliminary skull traction to all cases 6 cases reduced but later recurred and these were treated with halo vest fixation for three months. Of the rest only 5 which were irreducible were treated with operative methods, and all the remaining 25 were treated conservatively by Holter traction followed by application of Philadelphia collar for 8 weeks. It is interesting to point out a special category of patients we encountered where there was rotation of the axis about a fixed atlas, and although we had 8 of these patients we excluded them from this study.

CONCLUSIONS: Patients presenting early with traumatic rotatory subluxation can be treated only conservatively by traction if they present early.

Keywords: Rotatory Subluxation of C1C2 joint

FL-049

Spine

Management outcome (5 years or more) of paediatric vertebral hemangiomas presenting with myelopathy

Pankaj Kumar Singh, Sarat P Chandra, Shashank Sharad Kale

Department of neurosurgery, All India institute of medical sciences, New Delhi, India

BACKGROUND AND AIM: Vertebral hemangiomas are very rare in pediatric age group. In this study we analysed the outcomes of patient treated at department of neurosurgery, All india institute of medical sciences New Delhi since may 2010 to January 2022 with at least 5 year follow up.

METHOD: All patients up to 18 years age of vertebral hemangioma treated at our hospital from may 2010 to january 2022 with at least 5 year follow up. All had features of myelopathy.Patients demography, clinical details and follow up and complications were retrieved from hospital records. Functional clinical outcomes were measured using ASIA score. Mean age was 14.21 years with range of 12 years to 18 years. All patients had magnetic resonance imaging and computed tomography of spine in preoperative and postoperative period. Mean follow up was 78 months with range from 60 to 144 months.

RESULTS: There were 6 male and 8 female patients with sex ratio of 3:4. All were located in dorsal spine with single level involvement. Upper dorsal spine involvement was more common (10 cases 71.43%) than lower dorsal spine involvement (4 case 28.57%). All patients had weakness of lower limbs with features of myelopathy, urinary bladder symptoms were present in 6 patients local site pain in 1. D1 involvement was present in 1, D3 in 2, D4 in 2, D5 in 2, D6 in 3, D8 in 1,D10 in 1,D11 in 1 and D12 in 1. All patients have improvement in power of both lower limbs after surgery. Bladder symptom and pain resolved in all patients.

CONCLUSIONS: Good postoperative results can be achieved in pediatric symptomatic vertebral hemangioma with minimal complications. Individualization of treatment for each patient should be done with avoidance of selecting more blood loss procedures like corpectomies.

Keywords: Vertebral hemangioma

FL-050

Global Pediatric Neurosurgery

Development and validation of a Fast Spine Protocol for Use in Paediatric Patients

Winnie (Shu Yu) Wu¹, Elka Miller², Julie Hurteau Miller², Madhura Thipse³, Cassandra Kapoor², David McAuley⁴, Albert Tu⁴

¹Department of Medicine, University of Ottawa, Ottawa, Canada

²Department of Medical Imaging, CHEO, Department of Radiology, University of Ottawa, Canada

³Clinical Research Unit, CHEO, University of Ottawa, Ottawa, Canada

⁴Division of Neurosurgery, CHEO, University of Ottawa, Ottawa, Canada

BACKGROUND AND AIM: Conventional pediatric spine MRI protocols have multiple sequences resulting in long acquisition times. For many patients, sedation is consequently required. In brain imaging, indications such as hydrocephalus are now acceptably evaluated using a limited number of sequences resulting in shorter scan times and avoiding the need for sedation. This study evaluates the diagnostic capability of a limited MRI spine protocol for selected common pediatric indications.

METHOD: After REB approval, records of pediatric patients under 4 years of age who underwent a spine MRI at CHEO between 2017 and 2020 were reviewed. A blinded retrospective review by two neuroradiologists, limited to the T2 sagittal sequences from the craniocervical junction to sacrum and T1 axial sequence of the lumbar spine, was performed to answer specific questions regarding cerebellar ectopia, syrinx, level of conus, filum < 2 mm, fatty filum, and spinal dysraphism. The results were independently compared to previously reported findings obtained from the complete series of imaging sequences.

RESULTS: 105 studies were evaluated in 54 male and 51 female patients (mean age of 19.2 months). The estimated combined scan time of the limited sequences was 9–18 min compared to 24–36 min for conventional protocols (delta = 20–30 min). The average percent agreement between full and limited sequences was > 93% in all but identifying a filum < 2 mm, where the percent agreement was 87%. Using limited MR sequences had high sensitivity (> 0.97) and specificity (> 0.99) for the detection of cerebellar ectopia, syrinx, fatty filum, and spinal dysraphism.

CONCLUSIONS: This study demonstrates that highly selected sequences of spine imaging allows for consistent and accurate diagnosis of specific clinical conditions. The time required to obtain these sequences is substantially less than traditional imaging protocols and potentially avoids the need for sedation while increasing patient throughput. Further study is required to determine the utility of selected imaging for other clinical indications.

Keywords: Spine, Technical advances

FL-051

Spine

Efficacy of Selective Dorsal Rhizotomy and Intrathecal Baclofen Pump in the management of spasticity

Pramath Kakodkar¹, Hidy Girgis², Perla Nabhan³, Sharini Sam Chee⁴, Albert Tu⁵

¹Department of Laboratory Medicine and Pathology, University of Saskatchewan, Saskatoon, Canada

²Department of Neurosurgery, University of Ottawa, Ottawa, Canada

³Faculty of Science, University of Ottawa, Ottawa, Canada

⁴Schulich School of Medicine & Dentistry, Western University, London, Canada

⁵Department of Pediatric Neurosurgery, Children’s Hospital of Eastern Ontario, Ottawa, Canada

BACKGROUND AND AIM: Neurosurgical indications and interventions provided in the management of spasticity have evolved significantly over time. Selective Dorsal Rhizotomy (SDR) and Intrathecal baclofen (ITB) pumps have been used to improve mobility, reduce lower extremity spasticity, and increase quality of life in patients with various diagnoses.

METHOD: Studies describing ITB and SDR outcomes in adult and pediatric patients identified from Medline and Embase databases. Publications between January 1990–2021 were included. Combinations of search terms ‘Selective Dorsal Rhizotomy’, ‘Selective Posterior Rhizotomy’, 'functional posterior rhizotomy’, ‘intrathecal baclofen pump’, and ‘spasticity’ were used. Studies in English language and those that included parameters for lower extremity outcome (ie. Spasticity, ambulation) were included. Studies describing follow up 12 months or greater were included. Case reports, reviews without primary data, or inaccessible publications were excluded.

RESULTS: 290 publications between January 1990 to January 2021 were identified. Of these, 62 fit inclusion and exclusion criteria for a total of 1291 adult and 2263 patients. Predominant spasticity etiologies in the adult cohort comprised of multiple sclerosis, cerebral palsy, and trauma. In pediatric patients, cerebral palsy was the predominant etiology of spasticity. While outcomes after SDR and ITB varied, both are effective for long term tone reduction. SDR shows a greater effect on functionality compared to baseline in relatively similar subgroups. The complication rates for either intervention were significant; ITB had a greater incidence of wound and hardware adverse events whereas SDR had a not insignificant incidence of new bladder or sensory deficit.

CONCLUSIONS: ITB and SDR demonstrated efficacy and utility for tone reduction in a variety of conditions. The selection of a specific intervention may have a variety of determining features including the etiology of spasticity, age of patient, as well as balancing benefit and complication profiles of each technique. Appropriate patient selection is essential to providing optimal patient outcomes.

Keywords: Rhizotomy, Intrathecal baclofen pump, Adult, Pediatric, Spasticity, Selective dorsal rhizotomy

FL-053

Global Pediatric Neurosurgery

Incidence of Frontal Encephalocele in Brazil public health system: A 11-year analysis

Aline Rabelo Rodrigues¹, Carolina Carmona Pinheiro Machado², Ana Monize Ribeiro Fonseca³, João Victor Carvalho Da Paz⁴, Valdecir Boeno Spenazato Júnior⁵, Gabriel Bagarolo Petronilho⁷, Danielly Maximino Da Rocha⁷, Álvaro Alves De Sá Júnior¹, Matheus Fernando Manzolli Ballestero⁶

¹Medical School, Federal University of Jataí, Goiás, Brazil

²Medical School, University of Fortaleza, Fortaleza, Brazil

³Medical School, University of Tiradentes, Aracajú, Brazil

⁴Medical School, University of CEUMA, São Luís, Brazil

⁵Medical School, University of Vale do Sapucaí, Pouso Alegre, Brazil

⁶Assistant Professor, Department of Medicine, Federal University of São Carlos, São Carlos, Brazil

⁷Medical School, University Center of Assis Gurgacz Foundationn, Cascavel, Brazil

BACKGROUND AND AIM: Encephalocele is a common extracranial herniation of the meninges and brain tissue through a defect in the skull and dura. Is mostly common in the occipital region but has a classification based on the affected site: frontal (80% of western cases), occipital, sincipital (associated with craniofacial clefts), basal and posterior fossa. The aim of this study is to analyze the incidence of Encephalocele registered in Brazil in eleven years.

METHOD: We obtained the data in the Brazilian epidemiologic database (DATASUS) using the section for anomaly or congenital defect in live births with a number of diagnoses by the ICD-10 for congenital anomalies: Frontal Encephalocele (Q01.0), from 2010 to 2020, regardless of gender, maternal age and number of previous prenatal consultations.

RESULTS: There were a total of 107 cases of frontal encephalocele observed. There wasn't any increasing or decreasing pattern found during those eleven years gap, although the incidence was constant with a standard deviation of 2,1. There was a highest annual incidence of 12 cases, which occurred in 2010, 2016, 2018 and 2019, while the lowest number of cases occurred only in 2012, with 6 cases. All the data is on a 1 per 100.000 inhabitants scale.

CONCLUSIONS: The incidence of frontal encephalocele in Brazil, despite having years with higher and others with lower cases, a causal factor was not identified, moreover, was considered constant and It can be concluded that it is a prevalent comorbidity which can complicate. There is a need for early diagnosis, for better prevention, as well as better preparation of health professionals regarding rapid management in the emergency.

Keywords: Frontal encephalocele, Pediatric neurosurgery, Neural tube, Cranial vault

FL-054

Global Pediatric Neurosurgery

Pediatric Neurosurgery in an Indonesian Referral Hospital: A 4-Year Epidemiological Study

Yudistira Wardana, Andi Nugraha Sendjaja, Gumar Jaya Saleh

Department of Neurosurgery, Badan Pengusahaan Batam Hospital, Batam, Indonesia

BACKGROUND AND AIM: Indonesia faces various pediatric neurosurgery cases throughout the country. This retrospective study aimed to portray pediatric neurosurgery cases based on the data obtained from one of the Indonesian referral hospitals in the Riau Islands in hopes of providing useful information through epidemiological data.

METHOD: Registries and medical records from Badan Pengusahaan Batam Hospital, Batam, Indonesia, from January 2018 to December 2021 were compiled. Age, sex, and diagnoses were then analyzed and will be further discussed.

RESULTS: We obtained a total of 241 neurosurgery cases in children up to 17 years of age. We observed that most of the cases were male-dominated (61.4%), with the most affected age group in the range of 0–2 years old (34%), and the average was 7 years old. In a 4-year time period, the most cases that we found were trauma (47.7%), followed by hydrocephalus (19.1%), neoplasm (12%), infection (9.1%), dysraphism (5.4%), vascular (4.6%), and spine (2.1%).

CONCLUSIONS: Based on the study, we revealed that there were numerous pediatric neurosurgery cases that predominantly affected male patients, with trauma as the most common case found throughout the 4 years.

Keywords: Neurosurgery, Pediatric, Epidemiology

FL-055

Global Pediatric Neurosurgery

Outcome analysis in various indications for a pediatric decompressive craniectomy- Ambidirectional cohort study

Kashyap D Vyas, Arivazhgan Sathiaprabhu, Rameshkumar Ramchandran

Department of Neurosurgery, Jawaharlal Institute of Post-graduate medical education and research, Pondicherry, India

BACKGROUND AND AIM: In India, children < 15 years constitute 35% of the total population and contribute to 20–30% of all head injuries. To study the mortality and neurological outcome in pediatric patients undergoing decompressive craniectomy for various indications like traumatic and nontraumatic and to find out the Glasgow outcome scale (GOS) after 6 months of intervention.

METHOD: It was an Ambidirectional cohort study involving children aged ≤ 18 years who underwent decompressive craniectomy for traumatic and nontraumatic indications during the study period of the last 10 years retrospectively (before 2019) and prospectively up to December 2020 in our hospital.

RESULTS: We observed that 65 percent survived after decompressive craniectomy regardless of the indication. Out of those who survived, more than 70 percent have a better outcome scale. Our study shows a mortality rate of 35%, and the 48% of the patients showed good outcome (good recovery or moderate disability). The rest of the patients have a severe disability (17%), who are followed up for six months. Among non-traumatic indications coagulopathy group has poor outcome in terms of GOS. The most common indication of decompression in the pediatric group is a traumatic brain injury.

CONCLUSIONS: Traumatic patients fare well in terms of the outcome at six months as compared to the non-traumatic group. Out of the nontraumatic group, infective and cerebrovascular accident (CVA) etiologies are associated with better outcomes at six months and the coagulopathy group had the least favorable outcome. Henceforth, we suggest that decompressive craniectomy can be an effective way to reduce ICP and improve survivors' quality of life.

Keywords: Pediatric decompressive craniectomy, Glasgow outcome scale, Mortality and outcome analysis

FL-056

Global Pediatric Neurosurgery

Pediatric Neurosurgery in the Philippines

Manilyn Ann Hong

Division of Neurosurgery, Department of Neurosciences, Philippine General Hospital, Manila, Philippines

BACKGROUND AND AIM: It is known that there is great disparity to access to neurosurgical care between low-middle income and high income countries, with low-middle income countries having the heavier burden of pediatric neurosurgical diseases, such as hydrocephalus and myelomeningocele. The aim of the study was to describe the neurosurgical workforce in the Philippines managing these conditions.

METHOD: Cross-sectional analysis of the Academy of Filipino Neurosurgeons database as of December 2021 was performed, specifically focusing on the ratio of neurosurgeon per 100,000 population, ratio of male to female neurosurgeons and on the number of formally trained pediatric neurosurgeons practicing in the Philippines.

RESULTS: There are 128 licensed neurosurgeons in the Philippines, serving a population of 112,408,859 peoples, which is the 13th most populous in the world. The ratio is 0.11 neurosurgeon per 100,000 Filipinos. Of these 128 neurosurgeons, only 14 (10.9%) are practicing female neurosurgeons. There are 11 accredited neurosurgery residency training programs in the whole country, and within these training programs, there are 23 (29.9%) female neurosurgery residents. There are only 4 formally trained pediatric neurosurgeons in the country with a ratio of 0.01 pediatric neurosurgeon per 100,000 Filipino children. All 4 accomplished their fellowship training internationally since there is no pediatric neurosurgery fellowship training program in the Philippines.

CONCLUSIONS: In LMICs (e.g., Philippines, and others) where the number of neurosurgeons is scarce, general neurosurgeons manage both pediatric and adult conditions. Patients are managed by disease‐specialty instead of by age. Further bolstering of the neurosurgical workforce is needed in the Philippines, especially for pediatric neurosurgeons.

Keywords: Pediatric neurosurgery, Low-middle income countries

FL-057

Global Pediatric Neurosurgery

Current status of Myelomeningocele in Peru: A scoping review

Milagros Niquen Jimenez¹, Jesabelle De J. Dominguez Garcia², Danny Campos³

¹Facultad de Medicina Humana Alberto Hurtado, Universidad Peruana Cayetano Heredia, Lima, Peru

²Neuroscience Research Laboratory, Faculty of Health Sciences, Pontificia Universidad Católica Madre y Maestra, Santiago de los Caballeros, Dominican Republic

³Department of Neurosurgery, Instituto Nacional de Salud del Niño San Borja, Lima, Peru

BACKGROUND AND AIM: Neural tube defects (NTDs) are common congenital neurological defects in peruvian children. Our aim is to describe the current evidence regarding Myelomeningocele to highlight the gaps and interventions.

METHOD: We performed a scoping review under Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Scoping Review guidelines on peer-reviewed studies across the following databases: sciELO, LILACS, Redalyc, National Register of Research Projects, PubMed, and Google Scholar. A priori search criteria were established, we identify all articles related to Myelomeningocele in Peru published over the last twenty years. In addition, articles written in Spanish and English were included. Lastly, studies without a specific discussion regarding Myelomeningocele, focused on a different country, abstracts and case reports were excluded on the final analysis.

RESULTS: Of 3152 search results, 23 full text- articles were included. The main topic discussed was epidemiology, the second topic was treatment, and public health policy was the third topic. There is not a study that described the national epidemiology of myelomeningocele. Most of the epidemiological studies are based on the main city in Peru. According its results, Spina bifida-Myelomeningocele is the most common NTD. The prevalence of Myelomeningocele is related to low-socioeconomic status, low check-ups in the prenatal care, folate-deficiency, low maternal education, early and advanced maternal age, and overweight. The most frequent pathology associated was anemia. Neurological disorder was the main long-term side effects, followed by bladder dysfunction, and orthopedic disorders. The surgical treatment is delayed and the hydrocephalus is the most common surgical complication. The impact of fortifying wheat flour with acid folic was positive and effective at reducing folate-sensitive NTDs.

CONCLUSIONS: The present study represents the first overview regarding Myelomeningocele in Peru. There is currently a deficit of literature surrounding this topic. A national comprehensive approach should be incorporate to address this important unmet need.

Keywords: Myelomeningocele, Global pediatric neurosurgery, Public health, Peru

FL-058

Global Pediatric Neurosurgery

Low cost production of cranial moulding helmet in a LMIC setting

Jason Labuschagne¹, Denis Mutyaba¹, Wickus Neethling²

¹Nelson Mandela Children's Hospital

²University of the Witwatersrand

BACKGROUND AND AIM: Endoscopic suturectomy accompanied by the postoperative usage of a moulding helmet has shown good results in promoting cranial growth patterns and cosmetic outcomes. The cost of standard orthotic helmet production is frequently prohibitive, ranging from $1000-$3000 per helmet and hence not available to many patients throughout the LMIC setting. We investigated the in-house ability to fabricate an inexpensive and simple cranial moulding helmet. The premise of the technique was the ability to produce a low cost helmet, that could be made with hand-held tools and inexpensive materials. The technique should be replicable in any LMIC with access to the most basic equipment.

METHOD: All post-operative patients requiring orthotic moulding helmets had their helmets produced by a neurosurgical team member, none of whom had prior training in orthotic helmet production. A temporary cranial mould was made with crepe bandage and Plaster of Paris (POP). From this a POP cast was made. A rigid and adjustable moulding helmet was constructed over this cast from basic materials, including commercially available polypropylene plastic, high density foam, contact adhesive and a simple Velcro strap. Equipment required included a modified home oven, pliers, scissors and a DIY electric jigsaw.

RESULTS: A cranial moulding helmet could be successfully constructed using inexpensive materials. To date 5 such helmets have been produced. The patients have all been compliant with the helmet therapy. Parental acceptance of the helmet has been high and no parents have reported any perceived pain or discomfort from the helmet. No local skin reactions or irritation has been reported and no child has needed to discontinue using the orthotic.

CONCLUSIONS: Orthotic cranial devices produced in a LMIC setting can be simple and cost effective, and by using this method, optimal adjuvant therapy can be provided for patients following minimally invase craniosynostosis repair.

Keywords: Helmet orthotic therapy, LMIC, Craniostenosis, Global neurosurgery

FL-059

Neuroendoscopy

Endoscopic Third Ventriculostomy with Choroid Plexus Coagulation in 104 children under 1 year age

Carolina Belen Maldonado Alejos¹, Mariela Cecilia Salerno¹, Angel Nicolas Tello Brogiolo¹, Lucas Manuel Hinojosa¹, Juan Pablo Emmerich¹, Marcelo Osvaldo D´agustini¹, Ramiro J. Del Rio²

¹Sor Maria Ludovica Children´s Hospital, La Plata, Buenos Aires, Argentina

²National Pediatric Hospital Juan. P. Garrahan, Buenos Aires, Argentina

BACKGROUND AND AIM: The aim of this study is to demonstrate the efficacy of endoscopic third ventriculostomy (ETV) combined with choroid plexus cauterization (CPC) as the main treatment option in patients with hydrocephalus younger than 12 months and to describe the surgical technique.

METHOD: We followed patients with hydrocephalus less than 12 months of age whose hydrocephalus treatment from June 2013 to May 2022 was ETV with CPC. Patients were classified based on their etiology as: Hydrocephalus post infective (HPI), Hydrocephalus not after infection (HNPI), Posthemorrhagic hydrocephalus (PHH), and Myelomeningocele-related hydrocephalus (MMC-rH). The ETV Success Score (ETVSS) was used as a simplified means to predict the 6-month success rate of ETV in children with hydrocephalus based on age, etiology, and presence of a previous shunt.

RESULTS: We collected 104 patients with a mean age of 3.67 months and 39.42% were female. According to the etiology, 34 MMC-rH (32.69%), 33 PHH (31.73%), 24 HNPI (23.08%), and 13 HPI (12.5%) were found. The success rate was 64.42% for all procedures performed, regardless of etiology, with HNPI (70.83%), PHH (66.67%), HPI (61.65%), and MMC-rH. (58.82%). Success was more likely in infants less than 1 month of age. In 8 patients in whom ETV had failed, we performed RE- ETV and achieved resolution of hydrocefalus in 75% of them. Only in 29.81%, a shunt was required after ETV.

CONCLUSIONS: ETV-CPC Should be considered as a primary option in the treatment of hydrocephalus in patients less than one year of age, achieving shunt-free life in the majority of cases.

Keywords: Children, Endoscopic third ventriculostomy, Hydrocephalus, Surgical technique, Choroid plexus cauterization

FL-060

Other

Defining a taxonomical map for craniosynostoses: A unified functional-approach based nomenclature for interdisciplinary workflow in craniosynostoses management

Suhas Udayakumaran¹, Dilip Panikar², Pramod Subhash³

¹Division of Paediatric Neurosurgery, Department of Neurosurgery, Amrita Institute of Medical Sciences and Research centre, Kochi, India

²Department of Neurosurgery, Aster Medcity, Kochi, India

³Division of Craniomaxillofacial surgery, Amrita Institute of Medical Sciences and Research Centre, Kochi, India

BACKGROUND AND AIM: Craniosynostoses is a complex clinical and management challenge. This is further complicated by varying phenotypes, genotypes and specific challenges. Most complex craniosynostoses are approached and managed the same way despite the clinical variability, and patients often experience similar problems.

The descriptive diagnosis does not shed light on the issues or priorities, and most specialists dealing with these conditions remain in their field of tunnelled vision.

AIM: To create a goal-based universal and interdisciplinary language among various specialists involved in the management of craniosynostoses.

METHOD: Articles were searched in literature until January 1st, 2022, using search engines Pubmed, Embase and google scholar, using MeSH terms syndromic craniosynostoses, multisutural craniosynostoses, complex craniosynostoses, categorisation, classification, workflow, algorithm.

RESULTS: In this article, the authors propose a concept of categorisation based on initial patient presentation. The treatment status and the aetiology, if available, are incorporated along with the presentation.

Categorisation follows the process described in Fig. 1.

It has three components (Fig. 2):

• 1) Functional status (ICP. Airway, Aesthetic).

• 2) Aetiological status.

• 3) Treatment status.

Depicting the nomenclature (Fig. 3).

The craniofacial surgeon evaluates any patient at presentation clinically and assigns the categories based on the evaluation (Table 1).

I. The letter “C” would represent the category.

The subsequent letter would describe the presentation issue of raised ICP represented “I” and “A” for airway.

II. Incorporating the aetiological and genetic information if identified.

We propose to include the aetiological information in the categorisation as follows.

CATEGORY (AETIOLOGICAL DIAGNOSIS)

Or, if the aetiological diagnosis is not available, it will be denoted as.

CATEGORY(NOI) refers to not otherwise identified.

III. Incorporating treatment status (Fig. 3).

A superscript “T” will be added to the initial entries if treated.

CONCLUSIONS: The utility of our proposed categorisation is to create a goal-based universal language among various specialists involved.

Keywords: Algorithm, Syndromic craniosynostoses, Categorization, Nomenclature

FL-061

Neuroendoscopy

Endoscopic Resection of Nasional, Frontal and Frontozygomatic Subgaleal Dermoid Cysts In Infants

David F Jimenez Md, Facs, Faans

El Paso Children's Hospital, El Paso. Texas, USA

BACKGROUND AND AIM: Inclusion cysts are benign lesions that grow overtime and when present on the face and forehead can lead to a significant cosmetic deformity. Early resection of the lesions is indicated.

METHOD: A total of 26 children presented with growing and enlarging masses located and one of the following locations: A) Nasion:3 B) Mid supra-orbital: 6 C) Lateral supra-orbital: 14 D) Mid-frontal: 3. There were 11 males and 15 females. A 1.5-cm incision was made behind the hairline. Subgaleal dissection to the lesion was done with lighted retractor, zero- and 30-degree rigid endoscopes. Bloodless dissection was done with an extended needle tip bovie. Complete resection was done by cauterizing the pericranium around the lesion and removing it with pituitary rongeurs and sharp dissectors. The galea was closed with absorbable sutures.

RESULTS: A total of 26 children presented with growing and enlarging masses located and one of the following locations: A) Nasion:3 B) Mid supra-orbital: 6 C) Lateral supra-orbital: 14 D) Mid-frontal: 3. There were 11 males and 15 females. A 1.5-cm incision was made behind the hairline. Subgaleal dissection to the lesion was done with lighted retractor, zero- and 30-degree rigid endoscopes. Bloodless dissection was done with an extended needle tip bovie. Complete resection was done by cauterizing the pericranium around the lesion and removing it with pituitary rongeurs and sharp dissectors. The galea was closed with absorbable sutures.

CONCLUSIONS: Presented is a novel endoscopic approach to growing lesions located prominently of the patient’s face and forehead. All lesions were successfully removed without the need for visible incisions on the patient’s face. Technique and videos will be presented.

Keywords: Endoscopy, Dermoid cysts, Inclusion cysts

FL-062

Global Pediatric Neurosurgery

Cranial Expansion with Bifrontal Advancement and Spiral Parieto-temporal Craniectomies sparing partial superior-sagittal-sinus exposure in Syndromatic Craniosynostosis

Liana Beni Adani¹, Eran Regev²

¹Division of Pediatrics, Pediatric Neurology and Neurosurgery, Share Zedek Medical Center, Jerusalem, Israel

²Maxillofacial surgery, Share Zedek Medical Center, Jerusalem, Israel

BACKGROUND AND AIM: Management strategies for Syndromic Craniosynostosis patients require multidisciplinary subspecialty teams to provide optimal care for complex reconstructive approaches. Different approaches of Cranial vault remodeling were offered, using one or more cranial-remodeling surgeries in a patient, with staged separated anterior–posterior surgeries or one-stage fronto-orbital advancement, using different techniques of reconstruction, all aiming to relieve restriction of cranial development and treat intracranial hypertension (ICH). While maxillofacial intervention is usually advocated at older age, craniotomies are performed during the first year or when ICH is diagnosed. In the presence of elevated intracranial pressure, risk of Dural tear, significant bleed due to venous congestion, superior-sagittal-sinus damage, air emboli and hypothermia are only some of the possible complications of surgery, which is far more risky than reconstructive surgery for non-syndromic craniosynostosis without ICH. Extreme cranial expansion may lead to problematic scalp recovery, and ever-lasting bone defects, while minimal approach will probably demand future craniotomies for recurrent ICH. Expectations regarding achieving normal morphology should be carefully discussed with parents as well as the possible need of multistage interventions.

METHOD: Our protocol for "cranial expansion" included Bifrontal advancement together with parieto-temporal spiral-craniotomy following thin-strip para-sagittal bilateral craniotomies. The order of stages enabled gradual opening of the "strangulated" intracranial content, with relatively minimal bleed, starting with tight Dura and ending with pulsatile relaxed Dura, leaving most of the superior sagittal sinus covered.

RESULTS: This method was applied in a cohort of patients with syndromic craniosynostosis, achieving quick improvement of fundoscopy findings with resolving papilledema, stabilization of vision and good cognitive outcome. Follow up of up to 20 years in babies operated before the age of 14 months showed that compared to 2-stage posterior-then-anterior remodeling was helpful in avoiding recurrent intra-cranial hypertension.

CONCLUSIONS: Cranial Expansion with Bifrontal Advancement and Spiral Parieto-temporal Craniectomies sparing partial sss exposure is safe and effective in Syndromatic-Craniosynostosis.

Keywords: Spiral craniectomy, Intra cranial hypertension, Syndromatic craniosynostosis, Superior sagittal sinus

FL-063

Other

The natural history of untreated metopic synostosis: a morphological study

Ahmed Elawadly¹, Luke Smith¹, Alessandro Borghi², Adikarige Haritha Dulanka Silva¹, N U Owase Jeelani¹, David J Dunaway¹, Juling Ong¹, Greg James¹

¹Craniofacial Unit, Great Ormond Street Hospital, London, UK

²Great Ormond Street Institute of Child Health, University College London, London, UK

BACKGROUND AND AIM: The natural history of unoperated metopic synostosis is poorly understood, however crucial to answer the question of whether to treat such deformity. In this study, we used 3D surface scans to objectively evaluate morphological changes in unoperated trigonocephalic patients in different age groups.

METHOD: We screened our database for 3D scans of children with unoperated (pre-surgery or from children whose parents refused surgery) metopic synostosis between 2011–2021. Multisutural cases and benign metopic ridge were excluded. 3D surface scans (either 3D stereophotogrammetry or CT with skin reconstruction) for untreated patients were then enrolled for morphological analysis. 9 previously published parameters were used: frontal angle (FA30), antero-posterior volume ratio (APVR), antero-posterior area ratio (APAR), antero-posterior width ratio 1 and 2 (APWR1 and APWR2), and 4 antero-posterior diagonal ratios (rAPDR30, lAPDR30, rAPDR60, lAPDR60). We added a 10th parameter, the cranial vault asymmetry index (CVAI) for plagiocephaly.

RESULTS: 97 scans were identified for analysis from a total of 316 single metopic patients. Of the whole cohort, the male to female ratio was 2.7:1. Age at time of scan ranged from 9 days to 11 years stratified into 4 age groups: group 1: < 6 months, group 2: 6–12 months, group 3: 1–3 years, group 4: > 3 years. Posterior plagiocephaly was present in 35% of the cases, half of them were mild (CVAI category 2). Significant improvements were detected in 5 parameters (APVR, APAR, APWR1, rAPDR30, lAPDR30) over time (i.e. older children were less severe). No significant differences were found in CVAI, FA30, APWR2, rAPDR60, and lAPDR60 between age groups.

CONCLUSIONS: Forehead shape (surface area and volume), as well as narrowing and anterolateral contour at the medial supraorbital points, improved significantly over time without surgery. However, plagiocephaly, forehead angulation, narrowing, and anterolateral contour at lateral supraorbital points did not improve.

Keywords: Trigonocephaly, Metopic, Synostosis, Untreated, Morphological, Analysis

FL-064

Global Pediatric Neurosurgery

Long Term Cosmetic, Ophthalmological, Cognitive, and Parental Satisfactory Outcome after Open Sagittal Craniosynostosis Repair

Serife Maide Pinar¹, Tim Jonas Hallenberger², Maria Licci³, Benito K. Benitez⁴, Anja Palmowski – Wolfe⁵, Françoise Roulez⁵, Raphael Guzman², Jehuda Soleman²

¹Faculty of Medicine, University of Basel, Basel, Switzerland

²Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland

³Department of Pediatric Neurosurgery, University Children's Hospital of Basel, Basel, Switzerland

⁴Department of Oral and Craniomaxillofacial Surgery, University Hospital of Basel, Basel, Switzerland

⁵Department of Ophthalmology, University Hospital of Basel, Basel, Switzerland

BACKGROUND AND AIM: The aim of this study was to investigate the long-term cosmetic, ophthalmological, cognitive, and parental satisfactory outcome of children after open surgical correction for non-syndromic sagittal craniosynostosis.

METHOD: Patients under the age of twelve months, who underwent surgical reconstruction with a follow up period of at least 3 years after surgery at the Department of Pediatric Neurosurgery, University Hospital of Basel were included in this single center study. The primary outcome was parent-reported satisfaction of the surgery (PRSS) assessed through a parental questionnaire. Secondary outcomes were neurocognitive development and health-related quality of life (HRQoL), measured using the Vineland Adaptive Behavior Score (VABS) and the KINDL® questionnaire, ophthalmological outcome, and cosmetic outcome based on 3D imaging of the patients.

RESULTS: We included 26 children with a mean age of 7.67 months at surgery (15% girls). Based on PRSS 25% of the parents were satisfied and 75% very satisfied with the surgical outcome. VABS showed a mean of 104.52, corresponding to an overall age-adequate adaptive level. Children aged 4–6 showed a mean score of 79.76/100 for HRQoL, while children aged 7–13 showed a mean score of 76.04/100, which is within the norm. Cosmetic outcome based on 3D photos, and ophthalmological outcome will be presented as well.

CONCLUSIONS: Our preliminary results demonstrate, high parental satisfaction with the surgical repair of open sagittal synostosis. The patients do not seem to have more intellectual or developmental disabilities than the average of normal population while the HRQoL is within the norm.

Keywords: Sagittal craniosynostosis

FL-065

Other

Surgical correction outcome and satisfaction survey of craniosynostosis: A review of 241 patients in a single center from Romania

Mihaela Andrei¹, Sory Ibrahim Fofana², Ancuta Negru², Sorin Tarnoveanu²

¹University Hospital, Bucharest

²Marie Curie Children's Hospital Bucharest

BACKGROUND AND AIM: Provide postoperative outcome and parents satisfaction data after open surgical techniques performed at the largest national pediatric neurosurgery reference center,by a neurosurgical team treating 241 patients with syndromic and non-syndromic craniosynostosis.

METHOD: This retrospective study comprises 241 patients with diagnosis of premature closure of one or more cranial sutures confined to Marie Curie Children’s Hospital from Bucharest, Romania, between 2015–2021. During this interval 2112 patients underwent surgery from wich 241 cases of craniosynostosis. The importance of parents satisfaction during follow-up period is also discussed; a questionnaire was developed to evaluate the grade of satisfaction after surgery.

RESULTS: There were 72 females and 169 males; age at operation ranged from 4 to 23 months. There were 232 non-syndromic and only 9 syndromic craniosynostosis; of the varieties encoutered most common was fusion of sagittal suture only (53,1%), metopic (17,8%), lambdoid (17%),involving 2 sutures (8,3%) and syndromic craniosynostosis (3,8). Two patients associated hydrocephalus and needed ventriculoperitoneal device; ten patients associated decreased neurocognitive function at the first medical examination in our institution. Complications included 2 wound infections, 4 patients requiring reoperation for residual deformity from wich 2 patients underwent second surgery in our institution. The two other patients had no reoperation because of parents refusal or consent. There was no major postoperative long-term morbidity and no mortality during or after surgery.

CONCLUSIONS: Our review of 241 patients with craniosynostosis demonstrated good long-term results with an overal low complication rate and high degree of satisfaction in postoperative follow-up.

Keywords: Craniosynostosis, Syndromic, Non-syndromic, Satisfaction questionnaire

FL-066

Other

Coronal and lambdoid sutures evolution following total vault remodeling for scaphocephaly

Pierre Aurelien Beuriat, Alexandru Szathmari, Julie Chauvel Picard, Arnaud Gleizal, Carmine Mottolese, Federico Di Rocco

French Referral Center for Craniosynostosis, Hôpital Femme Mère Enfant, Lyon, France

BACKGROUND AND AIM: There are only a few reports on the evolution of sutures after surgical correction of craniosynostosis. The objective of this study was to.

understand the evolution of the cranial bones in the area of coronal and lambdoid sutures that were removed for complete vault remodeling in patients with sagittal craniosynostosis. In particular, the investigation aimed to confirm the possibility of neosuture formation.

METHOD: CT images of the skulls of children who underwent operations for scaphocephaly at Hôpital Femme Mère Enfant, Lyon University Hospital,

Lyon, France, from 2004 to 2014 were retrospectively reviewed. Inclusion criteria were diagnosis of isolated sagittal synostosis, age between 4 and 18 months at surgery, and availability of reliable postoperative CT images obtained at a minimum of 1 year after surgical correction.

RESULTS: Despite removal of both the coronal and lambdoid sutures, neosutures were detected on the 3D reconstructions. All combinations of neosuture formation were seen: visible lambdoid and coronal neosutures (n = 20); visible lambdoid neosutures with frontoparietal bony fusion (n = 12); frontoparietal and parietooccipital bony fusion (n = 3); and visible coronal neosutures with parietooccipital bony fusion (n = 2).

CONCLUSIONS: This is the first study to report the postoperative skull response after removal of normal patent sutures following total vault remodeling in.

patients with isolated sagittal synostosis. The reappearance of a neosuture is rather common, but its incidence depends on the type of suture. The outcome of the suture differs with the incidence of neosuture formation between these transverse sutures. This might imply genetic and functional differences among cranial sutures, which still have to be elucidated.

Keywords: Craniosynostosis, Neosuture, Scaphocephaly, Total vault remodelling

FL-067

Other

Total cranial vault remodelling including pterional decompression: increased frontal bossing correction in non-syndromic scaphocephaly patients [single centre restrospective and prospective case series]

Edward Jozef Baert

Department of neurosurgery, Ghent University Hospital (UZ Gent), Gent, Belgium

BACKGROUND AND AIM: Background and importance: surgical techniques to correct scaphocephaly often rely on foreign material and/or postoperative helmet therapy and fall short in correcting frontal bossing. Foreign material and helmet therapy are associated with side effects. Frontal bossing is perceived as a prominent, disfiguring feature of scaphocephaly, especially by the patients’ parents. We present the results of a total cranial vault remodelling (TCVR) which obviates foreign material and postoperative helmet therapy and corrects frontal bossing with a unique pterioneal decompression.

METHOD: METHODOLOGY: all patients, operated at a single institution between 2012 and 2020, were included in a retrospective review. Operation time, transfusion need, hospital stay, complications, cephalic index, and bossing angle were analysed. A prospective questionnaire was sent to the patients’ parents to evaluate how they assess their child’s skull.

RESULTS: 65 patients were included. Mean cephalic index was 69,2% preoperatively, 74,6% postoperatively, and 75,5% one-year postoperatively. Bossing angle was 114,5° preoperatively, 111,6° postoperatively, and 108,9° one-year postoperatively. The parents of 14 patients answered the questionnaire. All parents assessed their child’s skull as normal or almost normal one-year postoperatively. The mean operating time was 2 h and 4 min, median blood transfusion volume 100 ml. There were no complications.

CONCLUSIONS: The presented TCVR is as effective in correcting cephalic index and, due to a unique pterional decompression, more effective in correcting frontal bossing compared to (minimally invasive) alternatives. It is at least as safe and total treatment burden is lower as no helmet therapy nor foreign material is needed.

Keywords: Scaphocephaly, Frontal bossing, Cephalic index, Operative cranioplasty

FL-068

Other

Free Flaps Cranial Vault Remodelling for Sagittal Synostosis

Laura Grazia Valentini¹, Veronica Saletti², Alessandra Erbetta³, Mirella Seveso¹, Enrico Gambatesa¹, Ignazio Gaspare Vetrano¹

¹Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan

²Department of Pediatric Neurologist, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan

³Neuroradiology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan

BACKGROUND AND AIM: Best technique for Scaphocephaly (mininvasive vs open) is still debated, due to difficulties comparing aesthetic and functional RESULTS: cosmesis is hard to objectivate; cognitive and behavioural deficits are mild and need long term observation and complex testing to be quantified. Due to this uncertainty even surgical indications are discussed.

METHOD: We quantified results of our technique. 170 children were operated for sagittal synostosis as documented by 3DCT, with a male prevalence (133/37). At surgery 142 children (A) were < 1 (mean 6,8 months), 28 > 1 year (B). Multiple craniectomies were performed with high speed drill, by zig-zag bicoronal approach; bone flaps were programmed on preoperative-CT; two broad, symmetric fronto-parieto-temporal free flaps were created, than each was divided, leaving a residual bone at vertex upon the sagittal sinus 2–4 cm wide, to prevent venous damage and late diastasis. To allow vertical growth, this bridge was interrupted by 2–4 transversal cuts. Final shape was obtained by molding effect of brain growth, without rigid fixation. Continuous asorbable suturing (“Denim”) to improve the scar.

RESULTS: There was no mortality, neither infections; 2 children were re-operated to improve cosmesis, 1 for progressive bone defect and for 1 CSF collection. Aesthetics was judged by doctors and parents in 150 children by serial photos, Eco 3D and scar quality. Neuropsycological results were evaluated on testing and school performance, resulted in no delay in A children. Improvement of shape and volume was measured by cranial index graphs and on volumetric CT in 100 cases. At late MRI none of 65 evaluable A children presented CM while it was documented in 6/25 B children.

CONCLUSIONS: The present technique had low morbidity rate and good efficacy, correcting cephalic and vertical index, increasing intracranial volumes, so preventing CM1, preserving cognition and improving aesthetics. Another advantage was feasibility at any age, also in older children.

Keywords: Sagittal synostosis, Cranial volume, Surgery, Cranioplasty, Cosmesis

FL-069

Other

Long term follow up of the Leeds Fronto-Orbital Advancement and Reconstruction technique (reverse frontal bone graft without the use of the orbital bar)

Rebecca Chave Cox, Ariyo Onafowokan, James Robins, Paula Carter, Ojas Krishnan, Mark Liddington, Paul Chumas

Leeds Teaching Hospitals Trust, Leeds, UK

BACKGROUND AND AIM: We present our technique and outcomes using a reverse frontal bone graft without the use of the orbital bar to perform FOAR surgery. Having previously used the Marchac template technique and reversed frontal bone method utilizing the reshaped orbital bar we were often dissatisfied with the final shape of the orbital bar. We have evolved our current technique of drilling the orbital bar for use as bone dust/on-lay grafts and used this as our standardized FOAR technique since mid-2014.

METHOD: Between 2014 to 2021 we have performed 45 FOARs using this technique (23 metopic; 12 coronal; 7 sagittal & 3 multi-suture synostosis). Follow ranges from 1 to 7 years.

In our technique the frontal bone flap is reversed and new orbital rims are fashioned. This is advanced in cases of coronal synostosis but not metopic. We remove the orbital bar & use it only as graft material for bone dust, applying this at the temporal area or to any exposed dura. This aids bone fusion and prevents future defects.

RESULTS: Our 45 patients undergoing FOAR with this technique had good cosmetic outcomes, all constructs are stable and no revisions for cosmetic indications have been required. One patient had a wound infection requiring multiple wash outs and remains under review. One patient sadly died 3 years following the FOAR of unrelated causes. The vast majority of scars are hidden well, two patients have widened scars for which future revision has been offered should the families wish.

CONCLUSIONS: Our results show it is safe to remove the orbital bar all together and use it’s bone dust to fill gaps with good long term cosmetic results. This method has allowed us to standardise our FOAR method irrespective of the suture that is synostosed. Allowing flattening of the forehead and enabling advancement whilst preventing parietal thinning.

Keywords: Craniosynostosis, Metopic, Coronal, FOAR, Orbital bar

FL-070

Other

Bone changes of the cranial vault associated with intracranial hypertension in patients with craniosynostosis

Hector Velazquez Santana¹, Francisco J. Guerrero Jazo¹, Adrian Santana Ramirez¹, Martha Lilia Cisneros Avalos¹, Jaime Mora Rosales¹, Rodrigo Fraga Gonzalez¹, Nancy Elizabeth Gutierrez Hernandez¹, Yazmin Gisselle Figueroa¹, Miguel Angel Andrade Ramos¹, David Bañuelos Gallo², Fernando Chico Ponce De Leon³, Luz Monserrat Almaguer Ascencio⁴

¹Department of Neuroscience of Civil Hospital of Guadalajara Dr Juan I. Menchaca, Universidad de Guadalajara, Guadalajara Jalisco, Mexico

²Department of Radiology of Civil Hospital of Guadalajara Dr Juan I. Menchaca, Universidad de Guadalajara, Guadalajara Jalisco, Mexico

³Department of Pediatric Neurosurgery of Children’s Hospital Federico Gomez, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico

⁴Department of Neuroscience of Civil Hospital of Guadalajara Dr Juan I. Menchaca, Universidad de Guadalajara, Guadalajara Jalisco, Mexico; Department of Pediatric Neurosurgery of Children’s Hospital Federico Gomez, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico

BACKGROUND AND AIM: The identification of children with craniosynostosis at risk of increased intracranial pressure is a diagnostic priority. This pressure has been related to digital impressions, cranial lacunae and the appearance of a beaten copper skull by some authors, with conflicting evidence about its real association.

OBJECTIVE: To associate bone changes of the cranial vault with intracranial hypertension in patients with craniosynostosis.

METHOD: An analytical cross-sectional study is presented in a sample of patients with craniosynostosis compared to patients without craniosynostosis, who were clinically evaluated for intracranial hypertension data and underwent imaging studies to search for this association.

RESULTS: 55 patients were included. The mean age was 12.6 months (SD 9.2). Males prevailed in the sample (54.4%).

For analysis, the sample was divided into two groups; patients with craniosynostosis ( 50.9%) and patients without craniosynostosis (49.1%).Of the patients with craniosynostosis, 50% had digital impressions, 67.9% had cranial lacunae, and 17.9% had a copper skull.

In contrast, only one patient without craniosynostosis presented digitiform impressions (3.7%), 22% had cranial lacunae and none had a copper skull.

Of the patients with craniosynostosis, 37.5% presented intracranial hypertension (n = 10). A higher digital impression score (t(26) = -5.272, p < 0.005) was observed in the group of children with hypertension and craniosynostosis (x = 5.1) when compared to the group of children without hypertension and craniosynostosis (x = 0.6). Likewise, a higher copper skull score (t (26) = -2.748, p = 0.011) was observed in the group of children with hypertension and craniosynostosis (x = 1.7) when compared to the group of children without hypertension and craniosynostosis (x = 0.11).

CONCLUSIONS: A statistically significant, moderate and directly proportional association was evidenced between patients with craniosynostosis and intracranial hypertension with presenting digitiform impressions, compared to the control group.

Cranial vault changes lacks clinical relevance in patients without craniosynostosis. On the contrary, the presence of them in patients with craniosynostosis should be monitored.

Keywords: Craniosynostosis, Intracranial hypertension, Beaten copper skull, Cranial lacunae, Digital impressions

FL-071

Other

Spring-assisted cranial vault expansion in the setting of multisutural craniosynostosis

Tatiana Protzenko¹, Antônio Bellas¹, Claudia Ribeiro², Fernanda Rolemberg³, Sayonara Gonzalez³, Dafne Horovitz⁴

¹Department of Pediatric Surgery, Division of Pediatric Neurosurgery, Fernandes Figueira National Institute of Health for Women,Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

²Radiological Department, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

³Laboratory of Genomic Medicine, Department of Medical Genetics, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

⁴Department of Medical Genetics, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFFFiocruz), Rio de Janeiro, Brazil

BACKGROUND AND AIM: Children with multi-sutural craniosynostosis are predisposed to small posterior cranial fossa due to the prematurely fusion of the cranial sutures. This can lead to intracranial hypertension, Chiari type 1malformation and hydrocephalus. The control of ICP was traditionally undertaken with FOA. However, this technique proved to be insufficient. Thus, posterior vault expansion plays a fundamental role in the initial approach of these patients. The aim of this study is to demonstrate the improvement of the compressive phenomenon of the posterior fossa in a cohort of 10 patients with complex craniosynostosis submitted to spring-assisted posterior vault expansion.

METHOD: Patients were selected from a cohort of complex craniosynostosis from march2018-dec2021. From a total of 100 patients with multisutural craniosynostosis, 10 patients underwent springs-assisted posterior expansion as a first approach. All patients underwent molecular analysis for craniosynostosis. All patients underwent a preoperative CTvenogram and a postoperative CTscan on spring removal. Posterior fossa volume, resolution of type 1Chiari malformation, need for reoperation and ossification extension were evaluated.

RESULTS: We identified patients with: Crouzon FGFR2 (2), Crouzon FGFR3 (2), Jackson-Weiss (1), Apert (1), Pfeiffer (1), non-syndromic (2 oxycephaly/1 brachycephaly).Age at spring installation ranged from 5–24 months (mean 11.8 m). As complication, 3 patients had spring exposure, without CSF leek or infection. Only 1 patient didn't receive blood transfusion. An important increase in the volume of the posterior fossa was seen. 5 patients had significant venous anomalies that would prevent open decompression of the foramen magnum. Of the 3 patients who had preoperative tracheostomy, 2 showed significant respiratory improvement and were decannulated. Control CT scan showed satisfactory ossification, without recurrences.

CONCLUSIONS: Spring-assisted expansion is a safe technique for cranial vault expansion in patients with multi-sutural craniosynsostosis. The increase in the posterior fossa volume can avoid the need for foramen magnum decompression, especially in patients with anomalous venous drainage patterns.

Keywords: Spring-assisted, Multi-sutural craniosynostosis, Syndromic craniosynostosis, Posterior vault expansion

FL-072

Other

Venous anomalies in hypoplastic posterior fossa: unsolved questions

Tatiana Protzenko¹, Antônio Bellas¹, Fernanda Rolemberg³, Claudia Ribeiro², Sayonara Gonzalez³, Dafne Horovitz⁴

¹Department of Pediatric Surgery, Division of Pediatric Neurosurgery, Fernandes Figueira National Institute of Health for Women,Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

²Radiological Department, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

³Laboratory of Genomic Medicine, Department of Medical Genetics, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFF-Fiocruz), Rio de Janeiro, Brazil

⁴Department of Medical Genetics, Fernandes Figueira National Institute of Health for Women, Children and Adolescents, Oswaldo Cruz Foundation (IFFFiocruz), Rio de Janeiro, Brazil

BACKGROUND AND AIM: Venous hypertension is an important factor related to intracranial hypertension in complex craniosynostosis. It is associated with jugular foramen stenosis or atresia with the development of collateral emissary veins, which generate potential risks for surgical intervention. Therefore, the study of venous anatomy is essential for surgical planning.The aim of our study is to analyze the preoperative venous outflow pattern of patients with multi-suture craniosynostosis.

METHOD: A prospective study from March/2018-March/2022 of 70 children with complex/syndromic craniosynostosis was performed. Patients underwent molecular analysis and CT venogram as preoperative planning. Venous outflow were studied: major venous sinus, jugular foramina, collateral emissaries in 9 points: frontal, parietal, mastoid and condylar emissaries (both sides) and transosseous occipital. Collateral emissaries were classified as 0-absent; 1-present; 2-engorged; 3-anomalous, in each point, so that a single child could score 0 when they had no collateral and 27 points as the maximum score.

RESULTS: 70 patients (43 syndromic and 27non-syndromic) were studied. Syndromes identified were:Crouzon-FGFR2(11),Crouzon-FGFR3(2),Pfeiffer(6), Apert(20),Muenke(3),Jackson Weiss(1), Saerthre-Chotzen(1).Patients with Crouzon and Pfeiffer syndrome had the highest scores, reaching a maximum value of 22 and 21, respectively. Among them, only one patient with crouzon had bilateral jugular foramen atresia. Likewise, we found a patient with Apert syndrome and bilateral jugular atresia, but with score of only 4 points. Some patients with Crouzon and Pfeiffer syndromes and collateral circulation scores above 15 shared the same mutation position in the FGFR2-gene.

CONCLUSIONS: Crouzon and Pfeiffer syndromes FGFR2-related are associated with the presence of exuberant collateral venous circulation, not necessarily associated with bilateral jugular atresia.Patients with Apert syndrome do not have such exuberant collateral circulation. The role of the genetic mutation position in the FGFR2 gene still needs to be further studied.Muenke and Saerthre Chotzen syndromes resemble nonsyndromic multisutural craniosynostosis.Therefore,genetic screening is important in the preoperative period to define the best approach of these patients.

Keywords: Venous outflow, Syndromic craniosynostosis, Jugular atresia, Crouzon syndrome, Pfeiffer syndrome

FL-073

Other

The Influence of Cerebellar Tonsil Reduction in the Surgical Treatment of Chiari I Malformations in Children

Dale M Swift¹, Bruno P Braga², Eric Montgomery¹, Bradley Weprin², Angela Price², Brett Whittemore², Mark Pernik¹, Rafael De Oliveira Sillero²

¹Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, United States

²Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, United States; Children’s Medical Center, Dallas, United States

BACKGROUND AND AIM: The ideal surgical approach for type I Chiari malformations remains one of the great debates in the field of pediatric neurosurgery. The role of tonsil manipulation including cerebellar tonsil resection is controversial. We aim to compare surgical outcomes in Chiari I patients treated with and without cerebellar tonsil manipulation.

METHOD: We retrospectively reviewed the records of 456 children consecutively treated surgically for Chiari I malformations at Children's Medical Center Dallas. Preoperative variables included MRI measurements of the degree of cerebellar tonsil herniation as well as other craniovertebral junction measurements. Procedures were classified into four groups: bone decompression with duraplasty (PFDD), PFDD with arachnoid dissection (PFDD + AD), PFDD with coagulation of at least one cerebellar tonsil (PFDD + TC) and PFDD with subpial resection of at least one cerebellar tonsil (PFDD + TR). Efficacy was defined as improvement in patient-reported symptoms, greater than 50% reduction in syrinx by length or AP width, and the rates of reoperation. Safety was measured as the rate of postoperative complications.

RESULTS: The mean age was 8.4 years (range: 3 months to 18 years). Fifty-one percent had syringomyelia. Mean follow-up was 29.4 months. Patients who underwent surgical procedures resulting in cerebellar tonsil reduction (PFDD + TC or PFDD + TR) had improved outcomes postoperatively when compared to those in whom the tonsils were spared (PFDD or PFDD + AD). Statistically significant improvement was noted in headache resolution (85.5% vrs 74.2%, p = 0.008), syringomyelia reduction (80.4% vrs 58.8%, p = 0.001) and rates of reoperation (3.1% vrs 8.3%, p = 0.023). There was no difference in complications between the groups. The use of tonsil reduction procedures was associated with greater degrees of cerebellar tonsil herniation.

CONCLUSIONS: In this single center retrospective series, cerebellar tonsil reduction, by either coagulation or sub-pial resection, resulted in superior reduction of headaches and syringomyelia in Chiari I patients with less need for reoperation and without increased complications.

Keywords: Chiari I malformation, Syringomyelia, Cerebellar tonsil resection

FL-074

Other

CSF leak after intradural cranial surgery in the pediatric population

Emma M.H. Slot¹, Tristan P.C. van Doormaal², Kirsten van Baarsen³, Menno R. Germans⁴, Nick Krayenbühl⁴, Luca Regli⁴, Eelco W. Hoving⁵

¹Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands

²Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands; Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland

³Department of Neuro-oncology, Princess Maxima Center for Paediatric Oncology, Utrecht, the Netherlands

⁴Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland

⁵Department of Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht; Department of Neuro-oncology, Princess Maxima Center for Paediatric Oncology, Utrecht, the Netherlands

BACKGROUND AND AIM: Cerebrospinal fluid (CSF) leakage is a complication with potentially serious consequences. This study aimed to establish the incidence of CSF leakage after intradural cranial surgery in the pediatric population. In addition, potential risk factors and complications related to CSF leakage in the pediatric population were evaluated.

METHOD: We performed an international multicenter retrospective cohort study in three tertiary neurosurgical referral centers. All patients aged 18 years or younger who underwent intradural cranial surgery between 2015 and 2021 with complete follow up and complete surgical report available were included. Burr hole and transsphenoidal procedures were excluded. The primary outcome measure was the incidence of CSF leakage, defined as leakage through the skin, within six weeks after surgery. Uni- and multivariable logistic regression analysis was done to identify risk factors for, and complications related to CSF leakage.

RESULTS: We identified 844 procedures, representing 692 individual patients. The most common indication for surgery was tumor resection (50.1%). The incidence of CSF leakage was 6.8%. The odds ratio of pseudomeningocele (7.0, 95% CI 3.9–12.5), meningitis (25.5, 95% CI 11.8–55.0) and surgical site infection (7.6, 95% CI 2.7–21.1) was higher for patients with CSF leakage compared to patients without. Risk factors for CSF leakage were hydrocephalus (OR 4.2, 95% CI 2.1–8.2) and craniectomy (OR 8.6, 95% CI 3.3–22.1). Invasive treatment (defined as CSF diverting procedure, lumbar puncture, puncture of the pseudomeningocele or surgical wound revision) was performed in 49.1% of cases. A mean of 5.8 days of prolonged hospital stay was contributed to CSF leakage.

CONCLUSIONS: CSF leakage occurs in 6.8% of the pediatric population after intradural cranial surgery. It has a serious clinical impact due to increased risk of infection, development of pseudomeningocele, necessity for invasive treatment and prolonged hospitalization. Preventative strategies should aim at adequately controlling hydrocephalus and avoiding craniectomies.

Keywords: Cerebrospinal fluid leakage, Pediatrics, Infection, Cranial surgery, Hydrocephalus, Craniectomy

FL-075

Hydrocephalus

Ventriculopleural shunts in a pediatric population: a review of 170 consecutive patients

Eisha A Christian¹, Jeffrey Quezada², Edward F Melamed², Carolyn Lai², J. Gordon Mccomb³

¹Department of Neurological Surgery, Kaiser Permanente Medical Center, Los Angeles, USA

²Division of Neurosurgery, Children's Hospital Los Angeles, USA

³Division of Neurosurgery, Children's Hospital Los Angeles, USA & Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, USA

BACKGROUND AND AIM: The authors sought to determine the outcome of using the pleural space as the terminus for ventricular CSF-diverting shunts in a pediatric population

METHOD: All ventriculopleural (VPl) shunt insertions or revisions done between 1978 and 2018 in patients were identified. Data recorded for analysis were: age, sex, weight, etiology of hydrocephalus, previous shunt history, reason for VPl shunt insertion or conversion from ventriculoperitoneal (VP) or ventriculoatrial (VA) shunt, valve type, nature of malfunction, presence of shunt infection or pleural effusion, and conversion to a different distal site.

RESULTS: A total of 170 patients (mean age 14 ± 4 years) with a VPl shunt were followed up for a mean of 57 ± 53 months. The reasons for conversion to a VPl shunt for 167 patients were previous shunt infection in 57 (34%), multiple abdominal procedures in 44 (26%), inadequate absorption of CSF in 34 (20%), abdominal pseudocyst in 25 (15%), and obesity in 7 (4%). No VPl revisions were required in 97 (57%) patients. Of the 73 (43%) patients who did require revision, the most common reason was proximal obstruction in 32 (44%). The next most frequent complication was pleural effusion in 22 (30%) and included 3 patients with shunt infection. All 22 patients with a clinically significant pleural effusion required changing the distal end of the shunt from the pleural space. Pleural effusion was more likely to occur in VPl shunts without an antisiphon valve. Of the 29 children < 10 years old, 7 (24%) developed a pleural effusion requiring a revision of the distal catheter to outside the pleural space compared with 15 (11%) who were older (p = 0.049). There were 14 shunt infections with a rate of 4.2% per procedure and 8.2% per patient.

CONCLUSIONS: VPl shunts in children under 10 years of age have a significantly higher rate of symptomatic pleural effusion, requiring revision of the shunt’s terminus to a different location. VPl shunt complication rates are similar to those of VP shunts. The technical difficulty of inserting a VPl shunt is comparable to that of a VP shunt. In a patient older than 10 years, all else being equal, the authors recommend the distal end of a shunt be placed into the pleural space rather than the right atrium if the peritoneal cavity is not suitable.

Keywords: CSF, Hydrocephalus, Pediatric population, Pleural effusion, Ventriculopleural shunts

FL-076

Hydrocephalus

Endoscopic lavage and subgaleal shunt insertion for the treatment of neonatal hydrocephalus: a 10-year single-center experience

Katerina Apostolopoulou, Ben Hall, John Duddy, Raenette David, Abhishek Nadkarni, Arthur Kurzbuch, Benedetta Pettorini

Department of Neurosurgery, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

BACKGROUND AND AIM: The purpose of the present study is to present our experience and access the effectiveness of endoscopic lavage and subgaleal shunt insertion in the treatment of neonatal hydrocephalus.

METHOD: A retrospective review of the clinical cases was performed through the medical records, from 2012 to 2021. 57 neonates (28 males, 29 females) were included in the study. The mean gestational age was 28 + 4 weeks and the mean age at surgery was 35 + 3 weeks. The underlying pathologies causing hydrocephalus included intraventricular hemorrhage (IVH, mainly grade III and IV) (86%), infection (5%), IVH with infection (3.5%), congenital hydrocephalus (3.5%) and IVH from a ruptured vein of Galen malformation (2%). The surgical management included insertion of subgaleal shunt in 42 patients (74%), endoscopic washout in 8 (14%) and a combination of the two in 7 (12%).

RESULTS: The subgaleal shunt has been diverted to a permanent one in 37 neonates and in 5 was removed, with no need for further neurosurgical intervention (88% and 12%, respectively). 7 neonates who had a washout required a permanent shunt insertion and one did well without further intervention (87% and 13%, respectively). All 7 patients who had a combined surgery also required a shunt. The mean time period of the second operation was 6 weeks. No major intraoperative complications were observed. CSF leak from the subgaleal pouch observed in 5 patients (10%).

CONCLUSIONS: Our findings are in agreement with the current literature and suggest that endoscopic lavage and subgaleal shunts can serve as excellent methods for temporizing hydrocephalus in neonates. Both are low risk procedures with very promising results and occasionally can offer a definitive treatment.

Keywords: Endoscopic lavage, Subgaleal shunt, Neonatal hydrocephalus

FL-077

Hydrocephalus

Predictive factors in the Management of Hydrocephalus and Cerebrospinal Fluid Related Complications in Pediatric Choroid Plexus Tumors: A Single-Center Experience

Mahmoud Abbassy, Mohamed Elbeltagy, Mohammad Elbaroody, Ahmed Atallah, Abd Elrhman Enayet, Madiha Awad, Mohamed Saad Zaghloul

Cancer Children hospital of Egypt, Cairo, Egypt

BACKGROUND AND AIM: The intimate relation between hydrocephalus and pediatric Choroid Plexus Tumors (CPTs) should attain special care owing to the high incidence of permanent Cerebrospinal Fluid (CSF) diversion in those patients with possible shunt related complications. To our knowledge, this is the first study that analyzes predictive factors that could be linked to permanent CSF diversion in children with CPTs.

METHOD: We included all cases who were treated between January 2012 and December 2018 upfront in our institute with a follow-up from 2 to 106 months. Children in whom ventriculoperitoneal shunts were placed before tumor excision were excluded. Demographic data, preoperative radiological findings, operative details, and postoperative management of hydrocephalus, and CSF-related complications were reviewed.

RESULTS: A total of 33 children with CPTs were included in our study, 22 children (67%) needed permanent CSF diversion methods. Age less than two years (p-value 0.016), CSF permeation in FLAIR/T2 sequence (p-value 0.03), and bilateral subdural hygroma (p-value 0.049) were related to the need for permanent CSF diversion. Location of the tumor, maximum tumor diameter; consistency of tumor, preoperative Evan’s index; preoperative midline shift, tumor pathology; extent of resection of tumor; postoperative duration of the external ventricular drain, and amount of blood in ventricles were not statistically significant. We found that CSF permeation in FLAIR/T2 sequence, vasogenic edema and intraoperative parenchymal invasion were statistically significant factors in relation to postoperative entrapped horn.

CONCLUSIONS: Hydrocephalus has an intimate relation with pediatric choroid plexus tumors. Placement of a shunt could be inevitable at the end in most of them. However, patients older than two years without CSF permeation in preoperative imaging, and who did not develop subdural hygroma or developed a mild form should be given a worthy trial of patience, and going for shunt placement should not be the first option.

Keywords: Choroid Plexus- Papilloma- Atypical- Carcinoma- Hydrocephalus

FL-079

Hydrocephalus

Do sensor reservoirs reduce radiation exposure and the invasive procedures to diagnose shunt dysfunction in children with complex hydrocephalus?

Stuart Sinclair Stokes, Jan Hardy, Liz Hinde, John Preston, Hesham Zaki, John Mcmullan, Veejay Bagga, Patricia De Lacy, Shungu Ushewokunze

Department of Neurosurgery, Sheffield Children's Hospital, UK

BACKGROUND AND AIM: A significant proportion of children with hydrocephalus can be very difficult to diagnose as shunt malfunction due to significant cognitive impairment and gastrointestinal co-morbidities. We sought to determine if there was a reduction in the radiation exposure, as well as the use of hospital resources after sensor reservoirs implantation and if the sensor reservoirs are reliable beyond the initial number of months.

METHOD: We reviewed 23 patients over the last 5 years who had a total of 28 Miethke reservoir sensors implanted on average 2.9 years ago. We reviewed their medical notes, the regional PACS database and the database of all sensor readings stored for each child. The radiological investigations were then screened for those requested for shunt malfunction. When patients underwent invasive investigations such as a Lumbar puncture or ICP monitor insertion due to ongoing symptoms despite shunt adjustments we used these events to check the precision of the sensor reservoirs and if they correlate with invasive readings.

RESULTS: The average radiation exposure for each child significantly dropped from 6.8 CT head scans/year before sensor implant, to 3.3 CT heads/year. There were 8 occasions when invasive intracranial pressures were determined and these closely correlated with the averaged sensor readings to within 3cmH20 despite an average of 2.3 years of being implanted, in the presence of good waveforms and baseline negative pressures with the shunt in a vertical position. The implantation of sensor reservoirs significantly reduced the exploration of functional shunts and invasive procedures to determine ICP by a magnitude of 4. However, an increase in infection presumably due to the increase in the length of the incision, shunt connections and foreign material.

CONCLUSIONS: The sensor reservoir is a useful tool in determining shunt dysfunction in children that are difficult to assess and reduce radiation exposure in investigating shunt malfunction in our institution.

Keywords: Shunt, Sensor Reservoir, hydrocephalus, complex hydrocephalus

FL-080

Hydrocephalus

CSF-space volumetric change following posterior fossa decompression in paediatric Chiari type-I malformation; a correlation with outcome

Sidharth Mantha¹, Liam Coulthard², Robert Campbell³

¹Department of Neurosurgery, Princess Alexandra Hospital, Brisbane, Australia

²Department of Neurosurgery, Gold Coast University Hospital, Gold Coast, Australia

³Department of Neurosurgery, Queensland Children's Hospital, Brisbane, Australia

BACKGROUND AND AIM: We have previously reported inferior post-operative clinical outcomes in younger children with Chiari type-I malformation (CIM). We sought to quantify the CSF volumetric changes pre- and post-decompression, in a paediatric cohort, to determine whether cisternal volume change is associated with clinical outcomes.

METHOD: In this retrospective clinical study, the CSF spaces of the posterior fossa (supracerebellar/quadrigeminal, prepontine, fourth ventricle, cisterna magna) were measured on magnetic resonance images pre- and post-operatively using a semi-automated method. Additionally, we describe a novel CSF space of the upper cervical canal incorporating the subarachnoid space from the foramen magnum to inferior cortex of C2 body, FM-C2 cistern. Morphometric measurements included the pB-C2 distance, clivoaxial angle, clival length, clival angle and Boogard’s angle. Volumetric and morphometric data were correlated with clinical outcomes at 4–12 months post-operatively as measured by the Chicago Chiari Outcome Scale (CCOS).

RESULTS: Of 59 adequate clinical cases, 57 and 36 patients had acceptable imaging for morphometric and volumetric analysis respectively. All CSF spaces measured had a significant increase in volume post-operatively (p < 0.05). There was no correlation between the change in volume or post-operative CSF volumes and CCOS. The pre-operative volume of the FM-C2 was positively correlated with total CCOS (Wald χ2(1) = 4.07 p = 0.049) and was significantly smaller in the 0–6 year age group (2.38 ± 1.27 ml vs. 3.67 ± 1.56 ml p = 0.014). No morphometric measurement changed significantly after surgery or demonstrated a relationship with CCOS.

CONCLUSIONS: Volumetric changes in the CSF cisterns of the posterior cranial fossa and upper cervical canal do not correlate with the age-related differences in clinical outcomes in paediatric CIM. The pre-operative volume of the FM-C2 cistern may have a role in predicting the likelihood of a beneficial post-operative outcome in paediatric CIM.

Keywords: Chiari malformation, Volumetric analysis

FL-082

Global Pediatric Neurosurgery

Connective tissue hypermobility/EDS and Chiari 1 malformation: Surgical indications and outcomes

Katherine M Hofmann¹, Nirali P Patel², Lawrence Davidson¹, Tiffany N Phan¹, John S Myseros¹, Chima O Oluigbo¹, Hasan R Syed¹, Daniel A Donoho¹, Robert F Keating¹

¹Department of Neurosurgery, Children's National Hospital, Washington, DC, USA

²Department of Neurosurgery, Georgetown University, Washington, DC, USA

BACKGROUND AND AIM: The rise of incidental Chiari 1 malformation (CM1) radiographic findings has led to uncertainty about appropriate therapeutic approaches for children with concomitant connective tissue hypermobility/Ehlers-Danlos Syndrome (EDS) and their myriad symptomatology. A retrospective review of surgical treatments and outcomes of patients with EDS was undertaken to ascertain appropriate surgical indications.

METHOD: Demographics, surgical management, and long-term outcomes were observed for patients with EDS and CM1 at a single center (Children’s National Hospital) and compared to our cohort of general CM1 decompressions since 2003.

RESULTS: 36 patients with EDS and CM1 who underwent decompression were observed over 18 years. In this cohort, 88.9% were female vs. 54.3% in our overall cohort (232 CM1 patients) (p < 0.01). EDS patients underwent 44% bone-only and 56% duraplasty decompressions, similar to the general cohort (p = 0.66). The EDS failure rate was 11.1% vs. 10.3% for the overall cohort (p = 0.89), with follow-up of 4.72 years vs. 3.74 years (p = 0.11).

Surgical indications were similar for both cohorts (EDS vs. general): headache (67% vs. 65%, p = 0.85), neurological changes (28% vs. 24%, p = 0.59), and syringomyelia (50% vs. 63%, p = 0.12). Both cohorts (EDS vs. general) showed improvement for syringomyelia (77% vs. 82%), headache (85% vs. 80%), and neurological issues (60% vs. 79%), with no statistical difference in outcomes. Although most patients manifested headache improvement, resolution of EDS pre-op headaches often required more time. Complications were minimal for both groups.

CONCLUSIONS: Concomitant presentation of patients with connective tissue hypermobility/EDS and CM1 often presents a therapeutic dilemma. Somatic complaints frequently mimic symptomatic CM1; thus, we must differentiate clinically relevant etiology from the MRI finding. Failure to appreciate the true cause of symptoms may lead to ineffective treatment and morbidity. Our experience with EDS and concomitant CM1 demonstrates equivalent surgical therapeutic efficacy, although additional time is often necessary for resolution of preoperative headache, with improvement persisting over time.

Keywords: Chiari 1 malformation, Ehlers-danlos syndrome, Syringomyelia, Connective tissue hypermobility

FL-083

Neuroendoscopy

Intracranial arachnoid cysts: what is the appropriate surgical technique? a retrospective comparative study with 64 pediatric patients

Mohammed Issa, Filippo Paggetti, Andreas W Unterberg, Ahmed El Damaty

Department of Neurosurgery, University Hospital Heidelberg

BACKGROUND AND AIM: Symptomatic intracranial arachnoid cysts (iAC) should be treated whether through microsurgical (MS), endoscopic (ES) fenestration or implantation of a cysto-peritoneal shunt (CPS) system. The aim of this study is to compare the clinical and radiological courses with focus on the complication and revision rates between the three operative techniques in pediatric patients.

METHOD: All patients below 18 years with symptomatic iAC whom their first surgical treatment occurred in our center between 2004–2021 were included in this mono-central retrospective comparative cohort study. Initial symptoms, cyst location, complication rate, clinical and radiological improvement, revision rate and hospital stay were compared between the three operative techniques.

RESULTS: Sixty-four patients; 32 (50%) MS operated (mean age 7.6 years), 22 (34.4%) ES operated (mean age 6.0 years) and 10 (15.6%) with CPS (mean age 3.0 years) were found. The most common initial symptom was headache with 46.9%, followed by nausea and vomiting within 32.8%. The highest revision rate with 50% was seen in the CPS-group with a mean follow-up of 71.7 months compared to 5 patients (22.7%) in the ES-group and 11 (34.4%) patients in the MS-group with a mean follow-up of 32.7 and 80.3 months respectively. 3 patients (13.6%) from the ES-group needed later a CPS, in comparison to 8 (25%) patients from the MS-group. Clinical improvement immediately after surgery was observed in 19 (86.4%) patients in the ES-, 31 (96.9%) in MS- and by 10 (100%) in CPS-group. The patients could be discharged from hospital after 9.5 days in the CPS-, 12.77 days in the ES- and 17.3 days in the MS-group, 1.2–3.86 days of ICU-stay were necessary in average.

CONCLUSIONS: ES is a safe and efficient technique which is being widely used nowadays as a treatment of symptomatic iAC. Although CPS carries the least surgical risks but on the long-term shows the highest revision rate.

Keywords: Arachnoid cysts, Neuroendoscopy, Microsurgery, Cysto-peritoneal shunt

FL-084

Hydrocephalus

Defining the relationship between elevated cerebrospinal fluid protein and paediatric ventriculoperitoneal shunt infection

Charles Yates¹, Michael Colditz³, Martin Wood¹, Norman Ma², Gert Tollesson¹, Amelia Jardim¹, Raymond Chaseling¹, Robert Campbell¹

¹Department of Neurosurgery, Queensland Children's Hopsital, Brisbane, Australia

²Royal Brisbane and Women’s Hospital, Brisbane, Australia

³School of Medicine, University of Queensland, Brisbane, Australia

BACKGROUND AND AIM: Ventriculoperitoneal shunt (VPS) device infection is extremely common, and carries great morbidity for patients, their families, and the healthcare system. Clinically, elevated cerebrospinal fluid protein (CSFp) is a suspected risk for VPS infection, however this is widely debated, and definitive evidence is lacking. We aim to assess the role of CSFp in predicting VPS infection in a large paediatric cohort.

METHOD: A retrospective review of VPS procedures at the Queensland Children’s Hospital between 2014–2019 was conducted. Any future positive CSF culture was identified as an infection and correlated to the average retrospective CSFp levels more than 90-days prior to the positive culture. Relationships between patient age, gender, hydrocephalus aetiology and infection organism were similarly assessed. Prior culture-positive CSF samples were excluded from protein analysis. A logarithmic correction was applied to CSFp (nl-CSFp) for statistical modelling.

RESULTS: 563 procedures were assessed in 268 patients. Fourty-six (8.2%) VPS procedures were conducted for infected VPS devices, in thirty-eight (14.2%) patients. Historical nl-CSFp levels were significantly higher in patients with a VPS infection compared to those with no infection in the study period, and predicted future infection (OR 3.34, 955 CI 1.04–10.92, p = 0.042). Age at presentation was similar between patients with infection and those without infection (6.7 ± 5.8 versus 6.5 ± 5.4 years, p = 0.789), and no significant differences in gender (p = 0.067) or etiology for hydrocephalus (p = 0.513) were observed.

CONCLUSIONS: Patients with a historically elevated CSF protein may be at significantly increased risk for CSF infection following VPS device insertion. These findings support the need for prospective assessment of interventions to reduce VPS infection rates in this high-risk patient group.

Keywords: Paediatric, Hydrocephalus, VPS, Infection

FL-085

Hydrocephalus

Ventriculoperitoneal shunt (VPS) survival from the neonatal period into adulthood-a single-center long-term retrospective study

Ido Ben Zvi¹, Elias Badin², Aswin Chari¹, Kristian Aquilina¹

¹Department of Neurosurgery, Great Ormond Street Hospital for Children

²Queen Mary University of London

BACKGROUND AND AIM: Insertion of a ventriculoperitoneal shunt is one of the most common procedures in pediatric neurosurgery. Nevertheless, it has one of the highest complication rates in the specialty, particularly in infants. Our objective was to define long-term survival for shunts inserted in infancy, and the factors related to VPS complications.

METHOD: This was a retrospective, single-center trial. Children aged less than one year upon VPS insertion with follow-up until transition to adult care (17-18yrs) were included. Kaplan–Meier (KM) & Cox-regression analyses were used to identify which factors, presurgical and surgical, were associated with shunt survival.

RESULTS: 291 infants who underwent insertion of VPS between 1990–2003 were included. The most common aetiology was intraventricular haemorrhage (43%), followed by congenital hydrocephalus (16.5%), myelomeningocele (10%) infection (5.8%) and others (24%). The vast majority of the VPS were parietal. During the follow-up period, 168 (57.7%) of the shunts were revised, at a median time of 14 months (IQR 4–71 months). Survival was 60% at 5 years, 45% at 10 years and 35% at 15 years. In univariable KM analyses, the location of the shunt (p = 0.81), hydrocephalus severity (p = 0.10) and aetiology (p = 0.87) were not associated with shunt survival. On Cox-regression analysis a longer length of the proximal catheter was significantly associated with decreased shunt survival (p = 0.002) with a hazard ratio of 1.24 (95% CI 1.05–1.46), whereas distance from the tip of catheter to the foramen of Monro was not (p = 0.54).

CONCLUSIONS: The only factor associated with VPS failure was proximal catheter length, possibly due to the proximity to the choroid plexus. VPS insertion in infancy has a very low long-term success rate that should be communicated to the parents of these infants. Although most revisions occurred within 1 year of insertion, 25% were performed more than 5 years post insertion, warranting long-term follow-up.

Keywords: Pediatric hydrocephalus, Ventriculoperitoneal shunt, IVH, Myelomeningocele

FL-086

Hydrocephalus

Risk Factors of Congenital Hydrocephalus: A Case–Control Study

Taher Ali¹, Reem Elwy¹, Bassante A El Razik², Mohamed A.R. Soliman³, Mohamed F. Alsawy¹, Ahmed Abdullah¹, Eman Ahmed⁴, Shurouk Zaki¹, Amany A Salem⁵, Mohamed A Katri¹, Mostafa Elhamaky¹, Haitham Kandel¹, Ahmed A Marei¹, Ahmed Almenabbawy⁶, Ahmed M.F. Ghoul¹, Ahmed A Hafez¹, Sarah Abdelbar¹, Reham Khaled Moharam¹, Ayman Hany⁷, Ahmed Hasanin⁸, Sascha Marx⁹, Steffen Fleck⁹, Joerg Baldauf⁹, Henry W.s. Schroeder⁹, Ehab Elrefaee⁶, Ahmed Zohdi¹

¹Department of Neurosurgery, Faculty of Medicine, Cairo University, Cairo, Egypt

²Global Health, Global Health Institute, Heidelberg University, Heidelberg, Germany

³Department of Neurosurgery, Faculty of Medicine, Cairo University, Cairo, Egypt; Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, United States; Department of Neurosurgery, Buffalo General Medical Center, Kaleida Health, Buffalo, New York, United States

⁴Department of Neurosurgery, Faculty of Medicine, Cairo University, Cairo, Egypt, Faculty of Biotechnology, Badr University in Cairo, Cairo, Egypt

⁵Department of Public Health, Faculty of Medicine, Cairo University, Cairo, Egypt

⁶Department of Neurosurgery, Faculty of Medicine, Cairo University, Cairo, Egypt Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany.

⁷Department of Obstetrics and Gynecology, Faculty of Medicine, Cairo University, Cairo, Egypt

⁸Department of Anaesthesiology, Faculty of Medicine, Cairo University, Cairo, Egypt

⁹Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany

BACKGROUND AND AIM: Hydrocephalus is the commonest brain disorder in children and is more common in low- and middle-income countries. Research output on hydrocephalus remains sparse and of lower quality in low- and middle-income countries compared to high-income countries. Most studies addressing hydrocephalus epidemiology are retrospective registry studies entailing their inherent limitations and bias. We aim to investigate child-related, parental, and socioeconomic risk factors of congenital hydrocephalus (CH) in a lower-middle-income country.

METHOD: An investigator-administered questionnaire was used to query parents of CH patients and controls that visited our institution from 2017 until 2021. We excluded secondary hydrocephalus and children older than two years at diagnosis. Univariable and multivariable logistic regression was performed to identify the factors affecting the development of CH.

RESULTS: A total of 741 respondents (312 cases and 429 controls) were included. There was an independent higher odds of CH among children with a family history of other similar central nervous system conditions (odds ratio [OR] = 2.93, 95% confidence interval [CI] = 1.24–7.34), other congenital anomalies (OR = 2.57, 95%CI = 1.38–4.87), parental consanguinity (OR = 3.67, 95%CI = 2.40–5.69), conceived via assisted fertilization (OR = 3.93, 95%CI = 1.57–10.52), with a housewife mother (OR = 2.66, 95%CI = 1.51–4.87), suffering a gestational disease (OR = 3.12, 95%CI = 1.96–5.03), not using periconceptional folic acid (OR = 1.92, 95%CI = 1.32–2.81), and an illiterate father (OR = 1.65, 95%CI = 1.02–2.69). Contrarily, maternal hypertension (OR = 0.22, 95%CI = 0.09–0.48), older age at delivery (OR = 0.93, 95%CI = 0.89–0.97), and more abortions (OR = 0.80, 95%CI = 0.67–0.95) were protective from CH.

CONCLUSIONS: Multiple parental, socioeconomic and child-related factors were associated with higher odds for developing CH. However, other factors seem to be protective against hydrocephalus.

Keywords: Congenital hydrocephalus, Epidemiology, Maternal, Paternal, Socioeconomic, Risk Factors, Low and Lower-middle-income Countries (LMICs)

FL-087

Hydrocephalus

The Care Provider Experience for Hydrocephalus in Vietnam: A Social Media Survey

My Quang Le¹, Can Do Thanh Dang¹, Lepard Jacob R², Dung Hanh Nguyen³, Thoa Thi To¹, Thanh Minh Nguyen¹, Thanh Van Tran³

¹Department of neurosurgery, Children hospital 2, Ho Chi Minh city, Viet Nam

²Department of neurosurgery, University of Alabama at Birmingham, Alabama, United State of America

³Cure neuro, Cure international, Canada

BACKGROUND AND AIM: Hydrocephalus is a significant cause of pediatric morbidity and mortality worldwide. The clinical experience with hydrocephalus in Vietnam is not well understood.

METHOD: We utilized a popular Vietnamese hydrocephalus social media page to provide a link to an online survey regarding the clinical experience of hydrocephalus from the family perspective. Data were colected between April 1, 2022 and May 20, 2022.

RESULTS: We received a total of 73 responses. The majority of respondents were (91.8%) mothers of the patient and 5.5% were fathers. Most patients represented were female (44/73,60.3%). Approximately half of patients (34/73,46.6%) were the first child. Nearly half were born via vaginal delivery, (33/73,45.2%). The age of mothers ranged from 22 to 41. Twenty patients were diagnosed with hydrocephalus in utero (20/73,27.5%). Pre-term delivery was reported in 21 patients (21/73, 28.8%). The majority of patients (59/73, 80.8%) were treated at a national level pediatric neurosurgical hospital. Over half of patients required only one surgery for treatment of hydrocephalus (39/73,54.4). Thirty patients underwent endoscopic treatment of their hydrocephalus (30/73,41.1%). The majority of patients (48/73,65.8%) reported no post-operative complications. Over half of patients (42/73, 58.3%) attend regular follow-up visits. Forty patients reported access to physical therapy services (40/73,54.8%). For an improved treatment experience families requested: A Vietnamese website for hydrocephalus, better community for hydrocephalus patients, access to physical therapy videos, protocolized care, education regarding long-term treatment outcomes, and livestream webinars for answering questions, and access to latest surgical techniques and equipment in Vietnamese hospitals.

CONCLUSIONS: In the absence of comprehensive clinical databases the care provider experience provides important insight into the experience and needs of hydrocephalus patients and their families in Vietnam. Social media platforms can be an important means of accessing these patients and families for education and providing resources.

Keywords: Vietnam pediatric hydrocephalus, Children hospital 2, Social media survey

FL-088

Hydrocephalus

Optimal timing of definitive cerebrospinal fluid diversion for post-haemorrhagic ventricular dilatation in preterm infants

Ernest Lee¹, Helen Smart², Mohammad Naushahi²

¹School of Clinical Medicine, University of Cambridge, Cambridge, UK

²Academic Department of Neurosurgery, Addenbrooke’s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK

BACKGROUND AND AIM: Intraventricular haemorrhage (IVH) remains a severe complication in preterm infants. Producing progressive post-haemorrhagic ventricular dilatation (PHVD), IVH can lead to brain injury and severe neurological disability. Temporising surgical interventions, such as insertion of ventriculosubgaleal conduits (VSGs) and ventricular access devices (VADs), aim to minimise damage by permitting intermittent diversion of cerebrospinal fluid (CSF), as required. For some infants, this progresses to requirement of definitive CSF diversion, most commonly in the form of ventriculoperitoneal shunts (VPSs). The optimal timing for VPS insertion is still debated as it is uncertain whether the benefits of intervening early outweigh the potential complications. This study aims to determine if the said complications are influenced by the timing of VPS insertion.

METHOD: We retrospectively reviewed all PHVD preterm infants managed surgically at our regional Paediatric Neurosurgical Centre since 2015. Outcomes and complications, including shunt mechanical failure, infection, need for revision and long-term neurodevelopment were compared between infants with different time intervals between temporising and VPS interventions.

RESULTS: We identified 48 infants with Grade II-IV IVH. Temporising interventions were performed in 34 patients, with 25/34 requiring subsequent VPS insertion. The time interval between interventions ranged from 12 to 181 days. VPS was the first-line intervention in the remaining nine patients. Complications occurred in patients across all time intervals, with the most common being shunt blockage, migration and infection. Eleven out of twenty-five patients required shunt revision. Similarly, we observed issues with hearing, vision, motor development and seizures in patients across all time intervals.

CONCLUSIONS: Our results indicate that complications occur both in patients who had a VPS inserted early or later following temporising measures. Given the complications observed and lack of evidence surrounding this important issue, this study should provide impetus for randomised control trials to ascertain optimal timing for definitive CSF diversion in these preterm infants.

Keywords: Intraventricular haemorrhage, Post-haemorrhagic ventricular dilatation, Ventriculoperitoneal shunts

FL-089

Neurotrauma/Critical Care

Admission for observation for children with isolated linear skull fractures. Is it really necessary?

Ido Ben Zvi¹, Galal Imtiaz², Martin Tisdall¹

¹Department of Neurosurgery, Great Ormond Street Hospital for Children

²University of East Anglia

BACKGROUND AND AIM: Pediatric head trauma is a common reason for emergency department (ED) referrals. Once a head CT scan demonstrates non-surgical pathologies, the UK national guidelines recommend admission for 24 h minimum observation and discharge based on neurological status and oral intake. We evaluated whether admissions for isolated skull linear fractures yielded additional benefit.

METHOD: This was a retrospective single-center analysis, based on the electronic referral database of a tertiary pediatric hospital. Pediatric patients (< 18) were included if they sustained a skull linear fracture on CT scan. Patients with additional traumatic intracranial findings on imaging (bleeding, pneumocephalus, edema, etc.) were excluded, as were patients with depressed, open or displaced fractures.

RESULTS: 258 patients met the criteria between 2019–2022. 209 fell, 17 had blunt-force trauma, 8 had road accidents and 27 had an unclear mechanism. Most children had parietal fractures (50.4%), followed by occipital (20%), frontal and temporal (7.7% each). 4% had skull-base fractures. 16% suffered from chronic illness at the time of injury. No cases of growing skull fractures were seen. Out of all the children presented to our institution, none needed neurosurgical intervention. Moreover, none of them needed a follow-up CT scan. Three were transferred from a first-tier hospital to our institution, none of whom because of a neurosurgical concern. Apart from these three, all the other children were admitted to a pediatric ward for 24 h observation and subsequently discharged. Non-accidental injury (NAI) was highly suspected in 6 children, 3/42(7%) with chronic illness, 3/216(1.4%) without. This difference was statistically significant (p = 0.017).

CONCLUSIONS: In this large cohort, none of the children presented had a change in management following their admission. None needed neurosurgical intervention or observation. NAI-suspicion was more prevalent in chronic illness. In children with isolated skull linear fractures, a short ED observation should be considered, followed by discharge based on neurological status.

Keywords: Linear skull fracture, Pediatric head trauma, Head injury observation

FL-090

Neurotrauma/Critical Care

Middle Meningeal Artery Embolization for the Treatment of Chronic Subdural Hemorrhage in the Pediatric Population

Marian Michael Bercu¹, Casey J. Madura¹, Paul A. Mazaris², Justin A. Singer²

¹Department of Pediatric Neurosurgery, Helen DeVos Children's Hospital, Spectrum Health, Grand Rapids, Michigan, USA

²Department of Neurosurgery, Spectrum Health, Grand Rapids, Michigan, USA

BACKGROUND AND AIM: Chronic subdural hematoma (cSDH) is a common condition in the adult population, associated with significant morbidity and mortality. Embolization of the middle meningeal artery (MMA-E) has been reported as an evolving treatment for the symptomatic or large cSDH in the adult population.

The treatment of cSDH in the pediatric population consists in surgical drainage of the large or symptomatic cSDH, either through fontanelle taps or with a subdural drains.

We report the only series of three infants treated with MMA-E, with no complications and initial promising outcomes.

METHOD: Three patients were treated with MMA-E: Patient 1: 8-month-old with an atypical presentation at the age of 5-month-old with bilateral extra-axial hygromas probably secondary to NAT, treated initially with a fontanelle tap followed by a right MMA-E due to a significant acute on-chronic, clinically asymptomatic hemorrhage. Patient 2: 8-month-old female, with a history of traumatic birth, was incidentally diagnosed with large bilateral cSDH and Frisen grade 3 papilledema as part of the work-up for newly diagnosed neuroblastoma. Patient was treated with fontanelle taps, Diamox, followed by bilateral MMA-E. Patient 3: Presented with increasing head circumferences, diagnosed with bilateral (left > right) cSDH in the probable setting of von Willebrand disease, treated concomitantly with a left MMA-E and a burr hole for surgical drainage.

RESULTS: Patient 1: No evidence of residual extra-axial collections at 3 months follow-up. Patient 2: Undergoing aggressive chemotherapy and stem cell transplantation with severe thrombocytopenia (< 25,000/uL); at one month of follow-up the cSDH were similar in size but with a more dominant chronic component; the papilledema has almost fully resolved. Patient 3: Post-op MRI revealed minimal residual cSDH, head circumferences decreased by approximately 1 cm at 2 weeks follow-up, MRI pending.

CONCLUSIONS: We report the only series of three pediatric patients, diagnosed with cSDH, treated with MMA-E with no complications and initial promising outcomes.

Keywords: Middle meningeal artery embolization, Pediatric, Infant, Chronic subdural hematoma

FL-091

Neurotrauma/Critical Care

Disturbances of functional connectivity between default mode network and cerebellar structures in patients with mTBI in acute stage. rsfMRI and DTI study

Maxim Ublinskiy¹, Natalia Semenova², Tolibdzhon Akhadov¹, Andrei Manzhurtsev², Ilya Melnikov¹

¹Clinical and Research Institute of Emergency Pediatric Surgery and Trauma

² N. M. Emanuel Institute of Biochemical Physics (IBCP), RAS

BACKGROUND AND AIM: Mild traumatic brain injury (mTBI) occupies one of the first places in children injuries. Among all brain networks at the resting state, the Default Mode Network (DMN) is the most widely studied network. The aim of this study is to examine functional connectivity in normal-appearing cortex in acute period of mTBI using rsfmRI.

METHOD: 34 MR negative participants were studied in age from 12 to 17 years (mean age – 14.5 years). Group of patients consisted of 17 children with mild traumatic brain injury in acute stage. 17 age-matched healthy volunteers comprised control group. All studies were performed at Phillips Achieva 3.0 T MRI scanner using 32-channel head coil. fMRI data were processed using functional connectivity toolbox CONN. Seed-based analysis was performed in order to reveal disturbances in functional connectivity.Statistical processing was performed using Statistica 12.

RESULTS: DTI analysis didn't show any changes in values of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) between two groups (see Fig. 1). No statistically significant differences in correlation strength between DMN parts were observed in two groups (see Fig. 2). Intergroup seed-based analysis revealed statistically significant (p < 0,05) difference in neural correlations between DMN parts and vermis (cerebellum structural part): positive link in control group and negative link in group of patients.

CONCLUSIONS: One of the most common symptoms of mTBI is dizziness as a result of impaired movements coordination.Vermis as an essential cerebellum part plays an important role in the vestibulo-ocular system which is involved in the learning of basic motor skills in the brain. Vermis aids in the synchronization of eye and motor functions in order for the visual field and the motor skills to function together.Our results show that mTBI appears to be a possible reason of connectivity malfunction in normal-appearing vermis.

Keywords: mTBI, rsFMRI, DMN

FL-092

Neurotrauma/Critical Care

Pediatric blast induced neurotrauma model in rats: Functional and Biochemical study

Sachin Jose Pulickal, Dhananjaya I Bhat, Bhagavatula Indira Devi, Dhaval P Shukla

National Institute of Mental Health and Neurosciences, Bengaluru, India

BACKGROUND AND AIM: Our current understanding on blast induced neurotrauma pathophysiology stems from animal experiments. There is a paucity of knowledge on blast effects on young developing brain. The aim of the study is to assess the neurocognitive effects of blast induced neurotrauma in paediatric rats and to assess the tau protein levels in rat hippocampus and correlate with neurocognition.

METHOD: 30 Sprague Dawley rats of age 3–5 weeks were choosen which corresponds to post weaning period of humans. These rats were divided into three groups, two of which were subjected to mild blasts generated by a blast tube(modified Reddy’s Tube) to produce BINT in rats and the third group was used as control. Rats then underwent radial arms maze test to look for learning and memory functions after which they were sacrificed. The rat hippocampal isolates were then subjected to tau protein assesment.

RESULTS: The sham rats reached the acceptable level of training at the end of 12 days of training whereas the test rats took 16-days of training that is an additional three days to reach the acceptable level of training. The mean (SD) of tau protein levels (pg/100 mg Tissue) in the rat hippocampal homogenates. Group: High Pressure Blast group was 14.61 (8.46), Low Pressure Blast group was 7.72 (2.74) and 6.29(2.38) in the control group. Tau protien accumulation was noted in the blast exposed rats when compared to control rats.

CONCLUSIONS: Mild blast induced neurotrauma produces learning and memory impairment in rat pups which increase with the severity of the blast wave pressures. Blast induced neurotrauma produces accumulation of tau in hippocampus of rat pups. The aim of the study is to assess the neurocognitive effects of blast induced neurotrauma in paediatric rats and to assess the tau protein levels in rat hippocampus and correlate with neurocognition.

Keywords: Blast induced neurotrauma, Blast effects in peadiatric brain tau protien accumulation in TBI

FL-094

Innovation and technology

A novel MRI protocol for the assessment of MRI-negative/suspected focal cortical dysplasia in children. A single institution pilot study

Ido Ben Zvi¹, Aswin Chari¹, Martin Tisdall¹, Zubair Tahir¹, Sophie Adler², Konrad Wagstyl², Kshitij Mankad³, Felice D’arco³

¹Department of Neurosurgery, Great Ormond Street Hospital for Children

²University college London

³Department of Radiology, Great Ormond Street Hospital for Children

BACKGROUND AND AIM: Focal cortical dysplasia (FCD) is a common cause of drug-resistant epilepsy in childhood. These are further subdivided into three types. The routine MRI epilepsy protocol includes 3D-T1, 3D-FLAIR, T2 and diffusion. While this suffices for many FCDs, up to a third of lesions are radiologically occult. Since there is a correlation between MRI-positive lesions and seizure prognosis, at Great Ormond Street Hospital a novel protocol was developed for improving FCD detection, which is assessed in this pilot study.

METHOD: Patients are assessed with the advanced protocol if they have a suspected FCD, or if they are lesion-negative, but have a presumed FCD based on either history or EEG findings. Children with hippocampal sclerosis are assessed as well. Patients are not candidates if they have gross clear abnormalities such as tuberous sclerosis, hemimegalencephaly, stroke etc. The advanced protocol consists of arterial spin labelling (ASL) with color mapping, magnetization prepared 2 rapid gradient echo (MP2RAGE) with edge-enhancing gradient echo (EDGE) enhancement and diffusion tensor imaging (DTI) hot-spots. Patients are also analyzed by the multi-centre epilepsy lesion detection (MELD), a machine-learning system designed to detect FCDs.

RESULTS: In this pilot study three patients with an MRI-negative lesion were proven as FCDs, two with EDGE-MP2RAGE and one with ASL color mapping. In two other cases suspected lesions on FLAIR were proven as false-positive by EDGE-MP2RAGE. One further patient was identified with gyral abnormality identified by MELD, that correlated with symptomatology and was then resected.

CONCLUSIONS: Using this novel approach, we were able to detect both so-called MRI-negative and false-positive lesions. We believe this approach will enable neurological/neurosurgical teams to acquire surgical targets more accurately and add invaluable information to the decision-making process of suspected CFDs. A prospective study is underway to assess the usefulness of this method.

Keywords: Focal cortical dysplasia, epilepsy, MRI-negative, MP2RAGE, EDGE

FL-095

Innovation and technology

The use of Contrast Clearance Analysis Software to differentiate Tumor from Radionecrosis in Pediatric Brain tumors: A Revolution?

Amanda De Oliveira López¹, João Gabriel Ribeiro Gomes², Henrique Queiroga Cartaxo⁵, Ernesto Henrique Rosler³, Francisco De Paula Ramos Pedrosa⁴

¹Pediatric Neurosurgery Department, Real Hospital Português do Recife-PE, Brazil

²Pediatric Neurosurgery Department, Real Hospital Português do Recife-PE, Brazil; Radiation Oncology Department, Real Hospital Português do Recife-PE, Brazil

³Radiation Oncology Department, Real Hospital Português do Recife-PE, Brazil

⁴Pediatric Oncology Department, Real Hospital Português do Recife-PE, Brazil

⁵Neurorradiology Department, Real Hospital Português do Recife-PE, Brazil

BACKGROUND AND AIM: To evaluate the experience of the first center in Brazil, and second in South America, using Contrast Clearance Analysis Software (Brainlab) to differentiate tumor recurrence from radionecrosis in the management of pediatric brain tumors.

METHOD: We analyzed pediatric brain tumors images with Contrast Clearance Analysis (CCA) Software from April 2021 to April 2022 in a Pediatric Oncology Center in Brazil. From 87 patients and 244 CCA images at our institution, we selected the pediatric patients (10.34%) with 23 CCA images. All images were obtained with 3 T MRI (Verio, Siemens), and a T1 contrast enhanced volumetric sequence (MPRAGE) was acquired at 5 min and 60 to 105 min. The images were transfered to CCA software. A fusion between the 2 MPRAGE sequences was made and a CCA colored map was calculated. The lesion studied was evaluated according to the color on the map: blue (active tumor) or red (radionecrosis) (Fig. 1). The results of CCA software were compared to conventional MRI sequences (diffusion/perfusion/ spectroscopy).

RESULTS: The median age was 12 years (Range: 4–17) and mean follow up was 17,12 months (Range: 2–41). Patient diagnosis were malignant tumor (3 patients), benign tumor (5) and brainstem tumor without biopsy (1). 3/9 patients were treated with single fraction radiosurgery and 6/9 with conventional Radiotherapy. At follow up, 33,3% of patients developed new symptoms and Control MRI with conventional sequences demonstrated signs of disease progression, however, at CCA software was radionecrosis (Fig. 2,3). 100% had complete symptoms relief after radionecrosis treatment (steroids and vitamin E), and two lesions practically disappeared (Fig. 4).

CONCLUSIONS: The CCA software is a new technological approach providing efficient distinction between tumor/radionecrosis. The methodology provides high resolution and easy to interpret images with high accuracy. The present study is the first to describe the CCA software contribution specifically in the management of pediatric brain tumors.

Keywords: Radiotherapy, Pediatric brain tumors, Radionecrosis, Contrast clearance analysis, Recurrence

FL-096

Neurotrauma/Critical Care

Preventing Falls from Windows in the Children of British Columbia

Ruth Mitchell¹, Meah Lamothe², Stephano Chang³, Ashutosh Singhal¹, Mandeep Tamber¹

¹Faculty of Medicine and the Division of Neurosurgery, University of British Columbia and British Columbia Children’s Hospital

²Faculty of Medicine, University of British Columbia

³Division of Neurosurgery, Department of Surgery, University of British Columbia

BACKGROUND AND AIM: Unintentional falls are the leading cause of non-fatal injuries in the pediatric population. Falls from windows commonly lead to serious injuries requiring costly, invasive interventions. We aim to describe the severe injuries sustained due to falls from windows in a province-wide pediatric population, to inform prevention initiatives.

METHOD: We searched the British Columbia Trauma Registry (BCTR) for patients treated at the provincial pediatric trauma service who had unintentional falls from January 1 2007 to December 31 2020. The trauma database, electronic and paper-based medical records were searched. Institutional ethics board approval was obtained.

RESULTS: We found 2420 patients admitted in the defined period with falls, 1605 having fallen from less than one metre. We focused on falls between one and six metres resulting in admission to the Intensive Care Unit, and falls more than six metres, for 168 patients in total. Falls from windows accounted for just over a third of the falls in this period, more than any other mechanism. The mode of transportation to hospital, length of hospital stay, and length of ICU stay were similar in falls from windows, and other falls. However falls from windows resulted in significantly greater rates of trauma team activation, and patients were more likely to have sustained a head injury. Falls were most common in the summer months, with a peak in August.

CONCLUSIONS: A significant proportion of falls in our pediatric population are falls from windows. Further analyses are planned with regard to the age, number of operative interventions, permanent disability, and death in this cohort when compared with other pediatric falls patients. If such a high incidence of falls from windows occurs in our relatively temperate climate, a similar injury pattern might be found in warmer climates. Seasonal patterns of injury may help inform prevention efforts.

Keywords: Trauma, Falls, Traumatic brain injury, Head injury, Window, Neurotrauma

FL-097

Innovation and technology

Feasibility and utility of Sodium Fluorescein in removal of brain and spine tumors in children: a pilot prospective study in 38 cases

Camilla de Laurentis¹, Fred Bteich², Alexandru Szathmari², Pierre Aurélien Beuriat², Matthieu Vinchon², Federico Di Rocco³

¹Università degli Studi di Milano Bicocca, Milan, Italy; Department of Pediatric Neurosurgery, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France

²Department of Pediatric Neurosurgery, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France

³Claude Bernard Lyon 1 University, Lyon, France; Department of Pediatric Neurosurgery, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France

BACKGROUND AND AIM: Sodium fluorescein (SF) is currently considered a valid adjunct in the resection of high-grade brain lesions in adults. Experiences in pediatric groups and in low-grade lesions are still limited in literature.

METHOD: The study prospectively included all patients with tumoral lesions of brain and spine operated from September 2021 to June 2022 in the Pediatric Neurosurgery Unit of Hôpital Femme Mère Enfant, Lyon. We injected SF at the dose of 5 mg/kg just before positioning the patient. Surgery was performed using a YELLOW560 filter at crucial times. Possible adverse events were monitored and at the end of surgery the first operator completed a questionnaire on fluorescence perception and utility.

RESULTS: We included 38 patients (0.2–17.6 years old). Low-grade lesions were 25 (23 WHO grade I tumors, 2 benign mesenchymal lesions), high-grade lesions 12 (2 WHO grade III, 8 WHO grade IV, 2 malign mesenchymal tumors), and 1 lesion was unclassifiable. Location was supratentorial in 21 cases, infratentorial in 12, and spinal in 5. Only one case of late adverse reaction (hypotension) was noted, but causality could not be definitively determined, and no sequelae were registered.

SF enhancement was found in 34/38 cases (90%), but it did not add any further information to the standard white-light vision to allow distinction between tumor and healthy tissue in 14/38 (37%). However, a clear utility of SF emerged in 20/38 (53%) of the surgeries by helping in determining infiltration borders or individuating difficult-to-reach locations. In particular, the surgeon found SF a useful tool in low-grade tumors (60%,15/25), especially when infiltrating in nature.

CONCLUSIONS: Thanks to its safety profile and to its utility even in certain low-grade lesions, SF may often play a role as a valuable adjunctive tool in the pediatric neurosurgeon armamentarium.

Keywords: Sodium fluorescein, Low-grade tumors, High-grade tumors, Feasibility, Utility

FL-098

Innovation and technology

The Combination of Virtual Surgical Planning and the Use of a Mixed Reality Viewer and Patient-Specific 3D-Models for Patient Consultation in Complex Craniofacial Cases

Malte Ottenhausen¹, Verena Fassl¹, Julia Heider²

¹Department of Neurosurgery, University Medical Center Mainz

²Department of Oral and Maxillofacial Surgery, University Medical Center Mainz

BACKGROUND AND AIM: The majority of patients with head shape anomalies due to craniosynostosis are presented within the first months of life, if presented later even single suture synostosis require extensive operations. Especially if the indication for surgery is mainly to prevent socialpsychological problems it is difficult for caregivers to balance the risk of the operation against the cosmetic result.

METHOD: We present our approach using VSP®solutions from Stryker in collaboration with 3D Systems to accurately plan the surgical procedure virtually with a 3D Systems Biomedical Engineer. We then transfer the data to Brainlab® Elements and present and discuss the preoperative CT scan and 3D photo as well as the virtually planned result interactively with the parents using the mixed reality viewer Magic Leap. During the operation we use patient-specific, disposable guides and splints to speed up the operation and achieve optimal results. Patients are followed up using 3D photography.

RESULTS: The possibility to demonstrate the expected results and the extent of the operation with the use of a Mixed Reality Viewer and Patient-Specific 3D models improves shared decision making.

CONCLUSIONS: The possibility to demonstrate the expected results and the extent of the operation with the use of a Mixed Reality Viewer and Patient-Specific 3D models improves shared decision making.

Keywords: Virtual surgical planing, Mixed reality viewer, 3D

FL-099

Innovation and technology

Laser Interstitial Thermal Therapy: preliminary results for the treatment of deeply seated brain tumors and focal epilepsies in children

Thomas Blauwblomme, Lelio Guida, Kevin Beccaria, Jeremy Peuchot, Marie Bourgeois, Rima Nabbout, Emma Losito, Nathalie Boddaert

Hôpital Universitaire Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France

BACKGROUND AND AIM: Laser Interstitial Thermal Therapy has emerged in the last decade as an innovative, successful minimally invasive surgical tool for the ablation of brain lesions. However it has been available in Europe only recently. Here, we wish to analyze our preliminary results in 14 children with deeply seated WHO grade I brain tumors or malformations of cortical development in term of clinical and radiological outcome.

METHOD: Monocentric retrospective study of a prospective database of 14 children consecutively treated with LITT in Necker. Surgery was performed with the VISUALASE system under MRI control, after robotic stereotactic placement of the laser fiber. We reviewed medical files and radiological imaging.

RESULTS: 14 children (16 procedures) were operated between February 2021 and may 2022 (M/F ratio = 1, mean age 10.6 yo;sd 3.9y). Indications for surgery were oncology in 3 cases (refractory to chemotherapy), and epilepsy surgery in 11 cases (tumor related epilepsy n = 5, FCD after SEEG recording n = 5, hypothalamic hamartoma n = 1). Two children had previous surgery (incomplete resection n = 1, stereotactic biopsy n = 1). Lesion localization was: left mesial temporo occipital (calcarine sulcus n = 2, fusiform gyrus n = 2), left insular cortex ( whole insula n = 1, anterior insula n = 2), left cingulum (n = 3), basal ganglia (n = 1), mesencephalon (n = 1), hypothalamus (n = 1). There were 2 perioperative complications: transient hemiparesis (insular case) and hydrocephalus (midbrain tumor) however no patients had permanent deficits. With a mean follow up of 7 months (sd 4.7 months) we noted: resolution of symptoms in 3/3 tumor cases, control of seizures (Engel Ia) in 10/12 cases. MRI evolution displayed after 3 months: a central T2 hypo intensity with a peripheral hyper T2 rim for MCD/hamartoma, and volume reduction in all tumor cases along reduction of the contrast enhancement.

CONCLUSIONS: This preliminary series shows that LITT is safe and efficient for children with deeply seated brain lesions both for oncologic and epilepsy treatments.

Keywords: Laser, LITT, Oncology, Epilepsy

FL-100

Neurotrauma/Critical Care

Diffusion-tensor imaging study of peadiatric acute mTBI

Andrei Manzhurtsev¹, Maxim Ublinskiy², Tolib Akhadov³, Natalia Semenova¹

¹Clinical and Research Institute of Emergency Pediatric Surgery and Trauma

²Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences

³Moscow State University

BACKGROUND AND AIM: Computed tomography and magnetic resonance imaging (MRI) are not sensitive to mild traumatic brain injury (mTBI). However, mTBI may cause changes in cerebral microstructure that could be found using diffusion tensor imaging (DTI). The aim of this study is to reveal possible microstructural disorders in grey and white cerebral matters of children in the acute phase of mTBI (no more than 72 h), not accompanied by any structural brain injury.

METHOD: 11 healthy subjects and 11 patients with mTBI (up to 41 + 19 h since the injury), mean age 16 + 2. Philips Achieva dStream 3.0 T and 32-channel SENSE head coil were used. The standard TBI MRI protocol was applied. No pathological changes in brain tissue of any subject were found.

DTI was performed in 32 directions and was processed in Philips Intellispace Portal software. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained in corpus callosum (CC), corticospinal tract (CST) and in thalamus.

Statistical analysis was performed in STATISTICA 12. The Mann–Whitney criterion was used to reveal the significance of group differences, p-value < 0.05 was considered significant.

RESULTS: FA and ADC measured in thalamus are sensitive to acute mTBI: FA is increased and ADC decreases. The trend to the FA increase in corpus callosum in mTBI group and the absence of any changes in this parameter in corticospinal tract were observed. ADC in both CC and CST is unchanged.

CONCLUSIONS: The results of this study signify the presence of microstructural damage in thalamus. The changes in diffusion parameters arise from the cytotoxic swelling that happens because of the alterations in metabolic processes caused by the traumatic impact. The trend to the growth of FA revealed in this work may witness for the process of microstructural damage “maturation”, causing these changes to be observed as significant at a later stage after injury.

Keywords: DTI, mTBI

FL-101

Neurotrauma/Critical Care

Safety and effectiveness of TINS (Trauma Infant Neurological Score) used by Pediatricians in the community primary care hospital in evaluating Infants with Head Injury

Liana Beni Adani, Nechama Sharon, Lucio Segal, Michael Ben Akun

Pediatric Division, Korall Children's Medical Center, Natanya, Israel; Assuta Medical Centers, Tel-Aviv, Israel

BACKGROUND AND AIM: Importance: Traumatic brain injury (TBI) is the major cause of disability and death among the younger population and Head trauma (HT) may be responsible for secondary and late brain damage. However, most infants will suffer from non-life threatening mild or moderate HT occurring in the community and will be evaluated by pediatricians in clinics or community hospitals. Minor falls, repetitive head injuries of the “starting to walk” infant, “unwitnessed” mechanism of trauma, shaken baby syndrome and “occult child abuse” are only few mechanisms that differentiate infants from older children. On the other hand, “defensive medicine” in developed countries often leads to unnecessary Brain Imaging (mainly CT), or transfer of infant to a tertiary care hospital in cases where conservative treatment and not neurosurgical intervention will be advocated. AIM: to validate TINS as an effective and reliable clinical tool for evaluating HT in infants and for decision making in the primary care community hospitals.

METHOD: Prospective study, in a primary care community hospital serving a population of 400,000 people. Case managers were pediatricians, with stand-by Senior Pediatric Neurosurgeonavailable 24/7 for Telemedicine or WhatsUp consultation. All CT scans performed were revised by neurosurgeon and senior radiologist. 200 Infants age < 2y were enrolled according to IRB approved protocol. TINS parameters (picture) clinical and radiological data were recorded, with follow-up at 1 and 12 months after HT.

RESULTS: TINS was reported by all pediatricians a “user-friendly” and practical tool in quick evaluation of infants in the pediatric emergency room of a primary care community hospital. 103 boys (51.5%) and 97 girls, age 11 + 6.6 months (median 11) (1- day to 24 months). TINS scored 1–3 in this population. CT was abnormal in 15, Follow-up (early/late) did not show focal neurological deficit.

CONCLUSIONS: TINS can be safely, easily and effectively used by Pediatricians in decision making for Infant-Head-Trauma.

Keywords: Tins, Infants, Head truma, Pediatric injury, CT

FL-102

Epilepsy

Chloride deregulation in Focal Cortical Dysplasia type 2

Naziha Bakouh¹, Reyes Castano², Cerina Chhuon³, Sorana Ciuria², Alice Metais⁴, Giulia Barcia², Emma Losito¹, Anna Kaminska¹, Marie Bourgeois¹, Rima Nabbout¹, Chiara Guerrera³, Edor Kabashi², Thomas Blauwblomme¹

¹Hôpital Universitaire Necker Enfants Malades, APHP, Université de Paris Centre, Paris, France

²INSERM U1163. Imagine Institute, Paris, Franc

³Proteomic Plateform, SFR Necker, INSERM US 24

⁴GHU Sainte Anne, Paris, France

BACKGROUND AND AIM: Focal cortical dysplasia type II (FCDII) are emblematic malformations of cerebral cortical development associated with epilepsy in children. Somatic mutations in the PI3/AKT/mTOR pathways have been identified in FCD Type II, and recently we showed GABAergic dysfunction secondary to abnormal expression of chloride co-transporters (CCC) NKCC1 and KCC2. However, the pathways linking the genetic alterations to functional abnormalities and altered physiological excitability are missing.

Here, we investigate a possible link between mTOR activation, and CCC deregulation through abnormal control of the WNK1/SPAK/OSR pathway.

METHOD: Ex vivo electrophysiological recordings were performed with Microelectrode arrays (MEA) in acute human cortical slices from pediatric patients operated of FCDII. The physical interactions between PI3K/AKT/mTOR and WNK1/SPAK/OSR1 proteins were investigated by co-immunoprecipitation. Expression studies were completed by western blot.

RESULTS: First, we recorded spontaneous interictal spikes from human FCDII slices incubated with artificial cerebrospinal fluid (ACSF); they were abolished after administration of mTOR inhibitors demonstrating the involvement of mTOR pathway in the occurrence of epileptic activity. Second, we revealed a physical interaction between mTOR and mSIN1 of mTORC2 with WNK1 and SPAK/OSR1 respectively; consequently mTORC2 increases the activation and the degree of phosphorylation of WNK1/SPAK/OSR1. Third, western blot analysis showed reduced levels of KCC2/NKCC1 ratio in FCD cortical slices as compared to the controls. Interestingly, inhibition of WNK-SPAK kinases with Staurosporine and N-ethylmalemide (dephosphorylate the Thr233 and Ser373 of SPAK) induced an increased KCC2 expression and rescued the KCC2/NKCC1 ratio in FCDII, along with blocage of epileptic activities in FCD cortical slices on MEA recordings. Eventually, treatment with mTOR inhibitors restored the KCC2/NKCC1 ratio along with a decreased activity of WNK/SPAK/OSR.

CONCLUSIONS: This study shows that mutations of mTOR pathway activates WNK/SPAK/OSR kinases, resulting in deregulation of cation chloride cotransporters in FCD, supporting epileptogenesis through dysfunction of GABAa inhibition.

Keywords: Focal cortical dysplasia, GABA, Chloride cotransporters, Proteomics, Epileptogenicity

FL-103

Functional

Impact of Selective Dorsal Rhizotomy on Upper Extremity Functional Independence in Children with Cerebral Palsy: A Case Series

Elise J Yoon¹, Erika Erlandson², Melisa Concepcion³, Sarah Hoelton³, Tess Woehrlen³, Doris Tong¹, Neena I Marupudi⁴

¹Division of Neurosurgery, Michigan State University College of Human Medicine, Ascension Providence Hospital, Southfield, Michigan, United States of America

²Department of Physical Medicine and Rehabilitation, Michigan State University College of Osteopathic Medicine, Sparrow Hospital, East Lansing, Michigan, United States of America

³Department of Physical Medicine and Rehabilitation, Wayne State University, Rehabilitation Institute of Michigan, Detroit, Michigan, United States of America

⁴Department of Pediatric Neurosurgery, Wayne State University, Children’s Hospital of Michigan, Detroit, Michigan, United States of America

BACKGROUND AND AIM: Selective dorsal rhizotomy (SDR) is performed in children with cerebral palsy to reduce lower-extremity spasticity. Although nerve rootlet transection is limited to lumbosacral rootlets in SDR, unexpected observations of upper extremity (UE) spasticity improvements have been reported. These secondary suprasegmental effects on tone have been qualitatively or quantitatively described in select UE muscle groups in a number of case series. However, studies on postoperative improvement in UE function is limited. We present a comprehensive assessment of the effect of SDR on upper extremity function and independence in activities-of-daily-living (ADL).

METHOD: Data were collected on consecutive patients undergoing SDR from December 2017 to February 2022 at a single institution. Inclusion criteria were age of 3–11, baseline Gross-Motor-Function-Classification-System (GMFCS) score of I-IV, and interval functional independence data. All patients underwent SDR via minimally-invasive single-level or interlaminar approach. Patients were evaluated preoperatively and postoperatively at 3-month intervals by a multidisciplinary team. We analyzed UE function, lower extremity (LE) function, and independence in ADL using the Functional Independence Measure for Children (WeeFIM) instrument. One-way ANOVA and longitudinal analysis were used to analyze WeeFIM scores over time.

RESULTS: Thirty-two patients underwent SDR from 2017 to 2022. Twenty-seven patients met inclusion criteria; 5 patients were excluded due to lack of interval WeeFIM data. There were significant differences between timepoints in 3 WeeFIM categories. There was significant improvement in ADLs from baseline to 6 months (34.41 ± 5.46 versus 42.72 ± 10.64, p =  < 0.001), LE dressing scores from baseline to 12 months (23.26 ± 11.60 versus 31.44 ± 9.71, p = 0.027), and baseline to 24 months (23.26 ± 11.60 versus 33.29 ± 11.18, p = 0.008).

CONCLUSIONS: Along with effectively improving lower extremity spasticity and function, SDR results in significant improvements in UE function and ADLs. The building evidence on suprasegmental effects may lead to expanded long-term functional benefits with SDR.

Keywords: Activities of daily living, Cerebral palsy, Functional independence, Rhizotomy

FL-104

Functional

Improvement of Breath Control after Selective Dorsal Rhizotomy in Children with Cerebral Palsy

Elise J Yoon¹, Erika Erlandson², Melisa Concepcion³, Sarah Choss³, Tess Woehrlen³, Doris Tong¹, Neena I Marupudi⁴

¹Division of Neurosurgery, Michigan State University College of Human Medicine, Ascension Providence Hospital, Southfield, Michigan, United States of America

²Department of Physical Medicine and Rehabilitation, Michigan State University College of Osteopathic Medicine, Sparrow Hospital, East Lansing, Michigan, United States of America

³Department of Physical Medicine and Rehabilitation, Wayne State University, Rehabilitation Institute of Michigan, Detroit, Michigan, United States of America

⁴Department of Pediatric Neurosurgery, Wayne State University, Children’s Hospital of Michigan, Detroit, Michigan, United States of America

BACKGROUND AND AIM: Selective dorsal rhizotomy (SDR) is performed in children with cerebral palsy to reduce spasticity. In addition to tone reduction and functional improvement, providers and caregivers anecdotally noted improvement in breath control and speech after SDR. Therefore, we sought to systematically evaluate for functional improvements in breath control and speech.

METHOD: Data were collected on consecutive patients who underwent SDR from December 2017 to February 2022 at a single institution. Inclusion criteria were age of 3–11, baseline Gross-Motor-Function-Classification-System (GMFCS) score of I-IV, and presence of both baseline and 12-month postoperative breath control data. All patients underwent SDR via minimally-invasive single-level or interlaminar approach. Breath control was measured by maximum phonation time (MPT), which assesses how long a patient can sustain an isolated vowel without a substantial decrease in volume. Patients were evaluated preoperatively and postoperatively at 3-month intervals by a multidisciplinary team including Neurosurgery, Physical Medicine and Rehabilitation, Speech Therapy, Physical Therapy, and Occupational Therapy. A paired t-test was used to compare baseline and 12-month MPT values. Longitudinal analysis was performed to assess the temporal change at the individual level.

RESULTS: Thirty-two patients underwent SDR from 2017 to 2022. Fifteen patients were excluded due to lack of interval breath control data. Seventeen patients had both baseline and 12-month MPT values. Thirteen patients increased in their interval MPT value; 2 remained the same, and 2 decreased. There was a statistically significant improvement in mean MPT values from baseline to 12 months after surgery (5.52 ± 2.86 versus 7.90 ± 5.03, p = 0.012).

CONCLUSIONS: To our knowledge, this is the first study reporting quantitative data demonstrating a significant improvement in breath control after SDR. Improvements in MPT may correlate with improvements in long-term breathing/lung function, endurance, communication, and cognitive skills. These findings may support counseling provided to caregivers on the expanded benefits of minimally-invasive SDR surgery.

Keywords: Breath control, Cerebral palsy, Rhizotomy

FL-105

Functional

Review of the targeting accuracy of robot-assisted deep brain stimulation electrode implantation in paediatric patients with use of Renishaw 3D Neurolocate module

Raenette David¹, Maria Rosaria Scala², Jonathan Ellenbogen¹

¹Department of Neurosurgery, Alder Hey Children’s NHS Foundation Trust, Liverpool, United Kingdom

²Department of Neurosciences and Reproductive and Odontostomatological Sciences, Division of Neurosurgery, University of Napoli Federico II, Naples, Italy

BACKGROUND AND AIM: Renishaw 3D neurolocate module is a frameless patient registration module that is designed for use with the Renishaw neuromate stereotactic robot. The long-term electrical stimulation via deep brain electrode implantation of the globus pallidus internus and subthalamic nuclei is particularly successful in a select group of pediatric patients. This study aims to provide an update on the review of targeting accuracy of deep brain stimulation (DBS) electrode implantation, in a single centre, comparing the use of standard frame-based techniques versus the Renishaw 3D neurolocate module.

METHOD: Twenty (20) patients underwent implantation of DBS electrodes under general anaesthesia during the period August 2018 through April 2022. All patients underwent robotic-assisted stereotactic implantation of the DBS electrodes with intraoperative 3D scanner confirmation of the final electrode position. These coordinates were compared to the planned entry and target; with attention to depth, radial, directional and absolute errors, in addition to Euclidean distance.

RESULTS: Of the forty (40) DBS electrode implantations, 55% employed Renishaw 3D neurolocate technology. 85% of targets were globus pallidus internus and the remaining 15% the subthalamic nucleus. The mean age was 11.0 years (range from 4 – 18 years), of which 75% were male. The median absolute errors in x-,y-,z- axes were 0.45 mm, 0.7 mm and 0.8 mm respectively with use of the Renishaw 3D neurolocate versus 0.4 mm, 0.8 mm and 1.3 mm with standard techniques. The median Euclidean distance from the planned target to the actual electrode position with Renishaw 3D neurolocate module was 1.55 mm vs standard frame-based techniques at 1.70 mm. No major perioperative complications occurred.

CONCLUSIONS: Stereotactic robot-assisted DBS implantation with the Renishaw 3D neurolocate module is safe for use in the pediatric population with good surgical accuracy. Renishaw 3D neurolocate module for robotic DBS surgery allows compatibility with the intraoperative 3D scanner and has the potential to improve surgical targeting accuracy and patient comfort.

Keywords: Neurolocate, DBS, Renishaw, Globus pallidus internus, Paediatrics

FL-106

Epilepsy

Responsive neurostimulation for pediatric epilepsy

Sandi Lam, Melissa Lopresti, Jeffrey Raskin

Department of Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, USA; Division of Pediatric Neurosurgery, Lurie Children's Hospital, Chicago, USA

BACKGROUND AND AIM: Responsive neurostimulation is approved by the United States Food and Drug Agency for implantation as a medical device for neuromodulation treatment for drug-resistant epilepsy. The device is approved for patients over the age of 18 years. Use in children is relatively rare. We describe our experience with a series of 7 children treated with responsive neurostimulation.

METHOD: A retrospective chart review was conducted. Patient demographics, clinical characteristics, surgical details, and outcomes were recorded.

RESULTS: 7 pediatric patients, ages 7—17 years old, underwent placement of RNS devices for drug resistant epilepsy. All patients were not resective surgical candidates. 6/7 patients had phase 2 invasive intracranial electrode monitoring: of the 6, 3 were with stereoEEG and 3 were with subdural grid and strip electrodes. 1 patient had one-step RNS placement based on preoperative workup. 6/7 phase 2 patients went on to have placement of RNS. Postoperative follow up time ranged from 6 to 15 months. 3/7 patients (43%) had over 90% seizure control, 3/7 (43%) had over 50% seizure improvement, and 1/7 (14%) had 25–50% improvement. There were no intraoperative or postoperative complications or adverse events.

CONCLUSIONS: Responsive neurostimulation in this pediatric patient series is safe and provides possibility of improved seizure control in children who are otherwise not candidates for resective epilepsy surgery.

Keywords: Pediatric epilepsy, Epilepsy surgery, Neuromodulation, Responsive neurostimulation, RNS

FL-107

Functional

Microsurgical DREZotomy as an alternative to Intrathecal baclofen pump for decreasing tone in spastic cerebral palsy

Nishant Goyal

All India Institute of Medical Sciences, Rishikesh, India

BACKGROUND AND AIM: Intra-thecal baclofen pump(ITB)for severe refractory spastic cerebral palsy is not a viable option in resource-constraint settings. Therefore, authors assessed the role of microsurgical DREZotomy(MDT) as an alternative for patients in whom the circumstances did not allow ITB placement.

METHOD: A prospective clinical study was conducted from August2016 to July2020.All patients of spastic cerebral palsy(with III-IV Ashworth grade)who underwent MDT were included.Pre-operative and post-operative Ashworth grade and GMFCS level were assessed along with any change in power,sensation and bladder functions post-operatively.At last follow-up,patients’ main care-provider was asked to rate the effect of surgery(on scale of 0–5)on ease of providing care related to six activities of daily living.

RESULTS: Seven patients(5 males,2 females)of spastic cerebral palsy with age range 6–21 years underwent MDT over the study period.Six patients had spastic diplegia and one had spastic hemiplegia.Preoperative Ashworth grade in all patients was 3–4 in various involved muscle groups.Four patients with spastic diplegia underwent MDT at L3-S1 level bilaterally,two patients with spastic diplegia and spastic bladder underwent MDT at L3-S4 level bilaterally whereas one patient with right-sided spastic hemiplegia underwent MDT at C5-T1 level and L3-S1 level on the right side.Post-operative Ashworth grade in all patients improved to 0–1.The improvement in mean Ashworth grade was from 3.14 + 0.378 preoperatively to 0.29 + 0.488(p-value = 0.000).Most care-providers reported improvement in their ability to do physiotherapy, positioning, clothing, ambulation and to maintain patient’s personal hygiene.Care-providers of six patients reported that they were likely to recommend MDT to another similar patient.

CONCLUSIONS: MDT is a cost-effective tool in deceasing limb spasticity in spastic cerebral palsy especially for those who cannot afford ITB placement.

Keywords: Microsurgical DREZotomy (MDT), Intra-thecal baclofen (ITB) pump, Spastic cerebral palsy, Modified ashworth grade, GMFCS (Gross motor functional classification scale)

FL-108

Epilepsy

Single-Institution Comparative Study of MR-guided Laser Interstitial Thermal Therapy (MRgLITT) Versus Open Corpus Callosotomy

Jeffrey Steven Raskin^1,2, Josue Ordaz³, Hailey Budnick³, Ramana Vishnubhotla⁵, Anthony Alfonso⁴, Quiting Wen⁵, Rupa Radhakrishnan⁵

¹Division of Pediatric Neurosurgery, Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois, USA

²Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA

³Department of Neurological surgery, Indiana University, Indianapolis, Indiana, USA

⁴School of medicine, Indiana University, Indianapolis, Indiana, USA

⁵Department of Radiology, Indiana University, Indianapolis, Indiana, USA

BACKGROUND AND AIM: Open corpus callosotomy (CC) poses a higher risk of perioperative morbidity and hydrocephalus than MR-guided laser interstitial thermal therapy (MRgLITT) for treatment of drop and generalized seizures without documented superiority. We present a single-institution comparison between CC and MRgLITT.

METHOD: A two-year retrospective review was performed on patients at our institution who underwent CC and MRgLITT (January 2019-January 2021). Demographics, surgical outcome data, hospital costs and interhemispheric connectivity with diffusion tensor imaging (DTI) were compared (two-tailed t-test at α = 0.05).

RESULTS: The average age in years was 9.3 and 11.4 for CC (n = 4) and MRgLITT (n = 9), respectively. Preoperative drop seizure frequency was higher in CC (25 vs 14.5 seizures/day P = 0.59). At 10-month follow-up, the reduction in drop seizure frequency was better in CC, but not significantly (93.8% vs 64.3%, P = 0.21). The extent of ablation of the corpus callosum did not correlate with seizure reduction (Pearson’s Coefficient = 0.09), although an inverse correlation between interhemispheric connectivity change (DTI analysis) and drop seizure frequency reduction was noted (Pearson’s = -0.97). Total hospital cost was lower in MRgLITT ($67,754 vs $107,111, P = 0.004), attributed to lower ICU (1.1 vs 4 days, P = 0.004) and total hospital stay (1.8 vs 10.5 days, P = 0.0001). Furthermore, post-operative hydrocephalus present in 75% of patients in the CC group compared with zero in the MRgLITT group.

CONCLUSIONS: The results indicate MRgLITT is potentially a safer and cost-effective alternative to the traditional CC with therapeutic equipoise. This study is limited by the number of patients hence further patient enrollment or multicenter study is warranted.

Keywords: Epilepsy, LITT, Laser surgery

FL-109

Epilepsy

Ketogenic diet for management of refractory epilepsy: Cost effectiveness of a dietary subvention program

Adrian Caceres¹, Priscilla Pereira Angulo², Dina Arrieta Vega³, Monica Chavez Lavagni⁴, Kattia Rojas Leon⁵, Katherine Chan Grant⁶

¹Epilepsy Surgery/Monitoring unit, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

²Epilepsy Surgery/Monitoring unit, Nutrition Department, National Childrens Hospital "Dr. Carlos Saenz Herrera", San Jose, Costa Rica

³Rheumatology Department, Hospital Mexico, San Jose, Costa Rica

⁴Dermatology Department, Hospital San Juan de Dios, San Jose, Costa Rica

⁵Psychology Department, Hospital San Vicente de Paul, Heredia, Costa Rica

⁶Colegio de Medicos y Cirujanos, San Jose, Costa Rica

BACKGROUND AND AIM: This study performed a clinical and economic evaluation among families enrolled in the Ketogenic diet program (KDP) in order to define the cost of each hospital admission related to status epilepticus (ER, ICU, general ward) and to contrapose these expenditures against the cost of maintaining the diet based on an average monthly expenditure by the health system and families of these patients.

METHOD: Descriptive retrospective study performed in 15 patients from the KDP from 2015 to 2020. We determined: the clinical and economic background of patients, cost of treating a decompensated refractory epilepsy patient in our institution, the institutional cost of treatment in KDP patients, the family monthly cost of maintaining an appropriate menu according to the KDP, analyzing cost/benefit ratio for patients and our health institution.

RESULTS: 15 patients were evaluated, ages from 4 to 13 Y, 11 (74%) were male and 4 (26%) female. The monthly pharmacological treatment of this group varied from $67 to $450 USD and the average monthly cost of purchasing nutritional items for maintenance of the KDP was between $225 and $257 USD.

100% of the patients showed a significant improvement in their clinical status, 2 are seizure free and 80% reduced their visits to the ER. Those who did require ER evaluation had 60% lesser admissions.

The average cost of ER evaluation and admission was calculated at $2159 USD, increasing to $4522 and $11,585 USD for patients requiring hospital and ICU admission per event.

CONCLUSIONS: Based on this cost analysis, the monthly subvention of a KDP for the treatment of refractory epilepsy is not only cost effective representing a 11.8, 5.6 and 2,2% of the cost of ER evaluation and treatment, hospital admission or ICU admission respectively, but also decreases the number of ER visits and hospital admissions by 80 and 60% respectively.

Keywords: Refractory epilepsy, Ketogenic diet, Seizure control, Cost ratio benefit, Status epilepticus, Epilepsy surgery

FL-110

Epilepsy

Non-pharmacological treatment options of refractive epilepsy in subcortical band heterotopia

Arthur R Kurzbuch, Benjamin J Cooper, Jonathan R Ellenbogen

Department of Neurosurgery, Alder Hey Children's NHS Foundation Trust, Liverpool, UK

BACKGROUND AND AIM: Doublecortin (DCX) is a neuronal migration protein encoded by the DCX gene.

DCX-related and X-linked neuronal migration disorders comprise classic lissencephaly and subcortical band heterotopia (SBH) which primarily affects females and is often associated with refractory epilepsy. SBH is also also known as double cortex and subcortical laminar heterotopia.

The aim of this study is to review the literature for non-pharmacological treatment options of refractive epilepsy in SBH.

METHOD: Following PRISMA guidelines we performed a systematic review in Scopus and PubMed databases and describe a case report, managed at our institution.

RESULTS: Twenty-six patients who underwent 29 non-pharmacological treatments were reported.

Mean age at seizure onset: 6.5 years (range 0.2–23) with female sex predilection (5.25:1). Mean age at invasive or non-invasive treatment: 21.5 years (range 6.5–51).

Ten patients underwent corpus callosotomy, 8 had temporal lobectomy with amygdalohippocampectomy. Three patients had focal cortical resection. Two patients respectively had multiple subpial transections, insertion of a vagal nerve stimulator, or deep brain stimulation of the bilateral anterior nuclei of the thalamus. One patient underwent responsive focal neurostimulation, another had transcutaneous stimulation of the vagal nerve.

Sixteen patients reported a reduction or the disappearance of the seizures, 1 patient had no improvement. The outcome of 2 patients was Class I, of 1 patient Class II, of 1 patient Class III, and of 5 patients Class IV according to the Engel Epilepsy Surgery Outcome Scale.

CONCLUSIONS: Corpus callosotomy and temporal lobectomy with amygdalohippocampectomy have been the predominant non-pharmacological treatment. The small number of cases reported precludes drawing a firm conclusion as to which non-pharmacological treatment is the superior option for refractive epilepsy in patients with SBH. The future relevance of procedures such as deep brain stimulation, responsive focal neurostimulation, transcutaneous stimulation of the vagal nerve, and also stereotactic laser interstitial thermal therapy remain to be seen.

Keywords: Subcortical band heterotopia, Double cortex, Subcortical laminar heterotopia, Epilepsy, Seizure, Treatment

FL-111

Epilepsy

Early surgical approaches in pediatric epilepsy – a systematic review and meta-analysis

Nicole Alexandra Frank¹, Ladina Greuter¹, Raphael Guzman², Jehuda Soleman²

¹Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland

²Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland; Department of Pediatric Neurosurgery, University Children`s Hospital of Basel; Faculty of Medicine, University of Basel, Basel, Switzerland

BACKGROUND AND AIM: Pediatric seizures potentially have a severe negative impact on child’s development. Drug-resistant epilepsy occurs in up to 30% of children suffering from seizures and about 10% qualify for surgical treatment. The aim of this systematic review and meta-analysis is to analyze the potential benefit of early epilepsy surgery in children concerning primarily seizure and developmental outcome.

METHOD: PubMed and Embase databases were searched using a systematic search strategy to identify studies on pediatric epilepsy surgery under 3 years from their inception up to 2022. Outcome measures were seizure outcome, postoperative complications, seizure onset and reduction rate of antiepileptic drugs. A meta-analysis was thereafter performed for all included cohort studies. A p-value of < 0.05 was considered as statistically significant.

RESULTS: A total of 532 patients were analyzed with 401 patients (75%) receiving resective or disconnective surgery under the age of 3 years and 80 patients (15%) receiving surgery older than 3 years. The remaining 51 patients (9%) underwent VNS-implantation. Pooled outcome analysis for resective/disconnective surgery showed favorable outcome in 68% (95% CI [0.63; 0.73]), while comparative analysis between the age groups showed no significant difference (77% early group and 75% late group; RR 1.03, 95% CI [0.73; 1.46] p = 0.75). Favorable outcome for the VNS-cohort was seen in 52%, 65% in the early and 45.1% in the late group (RR 1.4393, 95% CI [0.87; 2.4] z = 1.42, p = 0.16). Developmental outcome was improved in 26%, 8.2% remained stable. Morbidity rate was moderate and showed no significant difference comparing the age groups, overall surgical mortality rate was very low (0.1%).

CONCLUSIONS: Epilepsy surgery in pediatric age, especially under the age of 3 years, is a feasible and safe way to treat intractable epilepsy and therefore to potentially prevent severe developmental and cognitive deterioration. Further comparative studies of prospective nature should be the focus of future studies.

Keywords: Pediatric epilepsy surgery, Intractable epilepsy, Drug-resistant epilepsy, Pediatric neurosurgery

FL-112

Epilepsy

Spatiotemporal Mapping and Characterization of Oculomotor Control in the Pediatric Frontal Eye Fields

Stephano J. Chang¹, Mohammad Mashayekhi², Hetshree Joshi¹, Ash Singhal³, Mandeep Tamber³

¹Division of Neurosurgery, Department of Surgery, University of British Columbia, Vancouver, Canada

²Faculty of Medicine, University of British Columbia, Vancouver, Canada

³Faculty of Medicine and the Division of Neurosurgery, University of British Columbia, Vancouver, Canada

BACKGROUND AND AIM: The frontal eye fields (FEFs) are linked to oculomotor control and hypothesized to reside in the prefrontal cortex, where electrical stimulation reportedly evokes contraversive eye movements. The exact location and function of the FEFs in humans is controversial with studies implicating multiple putative regions, including the posterior middle frontal gyrus and the inferior precentral gyrus. Stereo-electroencephalography (SEEG) is a minimally invasive technique used to guide epilepsy surgery. It provides a unique opportunity to collect human neurophysiological data outside of the operating room and has been used by other groups to advance our understanding of specific brain functions.

METHOD: Four pediatric subjects undergoing non-lesional epilepsy workup were enrolled into this prospective, IRB-approved study, and received brain MRI prior to SEEG implantation, followed by post-operative CT head for electrode localization. Post-operative stimulation testing and SEEG recordings were performed along with time-aligned video of the subjects’ eyes while performing gaze-related tasks.

RESULTS: Stimulation testing elicited contraversive head turning with or without eye deviation, and hemifacial spasm, depending on the site of stimulation. Low-threshold sites eliciting these stereotyped movements were located just deep to the inferior precentral gyrus. Stimulation of sites in the posterior middle frontal gyrus did not elicit eye deviation movements in our two subjects in the post-operative setting. Preliminary univariate decoding of raw SEEG from electrodes in the inferior precentral gyrus revealed high correlations to eye movements at lower frequencies, which likely represent relevant features for eye movement control and will likely be an important component of multivariate decoding processes.

CONCLUSIONS: Our findings suggest that the FEFs are located more posteriorly than widely held, involving the motor cortex. Further testing in pediatric and adult subjects is warranted to confirm this hypothesis and test for differences in these populations.

Keywords: Frontal eye fields, Stereo-electroencephalography, Electrical mapping, Oculomotion, Neural decoding

FL-113

Dysraphism

5-year outcomes following Selective Dorsal Rhizotomy – the Leeds experience

Rebecca S Chave Cox, Kate Mccune, Katie Davis, Kit Tzu Tang, Shona Michael, Rajib Lodh, John R Goodden

Leeds Teaching Hospitals Trust, UK

BACKGROUND AND AIM: Selective Dorsal Rhizotomy surgery aims to improve function and mobility through reduction in lower limb tone. In the UK it is offered to suitable patients who have spastic diplegia with GMFCS levels II-III and meet the NICE selection criteria. We present the long term (5 year) Quality of Life (QoL) outcomes from the first patients treated in our centre.

METHOD: The first SDR procedure was in October 2012. Post-operative outcomes are prospectively recorded using a spreadsheet database, > 150 patients treated to date.

SDR is performed by a single surgeon with the same technique (single level) and standardized 3-week post-operative physiotherapy regime. Intra-operative neurophysiology is always used. Patient selection criteria are: spastic diplegia with dynamic spasticity limiting function, no dystonia, typical MRI changes, GMFCS Level 2 or 3. Orthopaedic input is provided as required in line with NHS guidance.

All patients have standardised pre- & post-op assessments with 3D Gait Analysis, GMFM-66, Ashworth grading, muscle power & joint range of movement. Quality of Life (QoL) is assessed using the CPQoL questionnaire.

RESULTS: Overall 152 patients have been treated with SDR in Leeds, with 5-year follow-up assessments completed for > 70. Early post-operative results have previously been presented.

In this presentation we present the multi-modal outcomes for QoL, tone, power and function for patients with completed 5-year follow-up – mapping their progress since surgery. All patients have a reduction in tone after SDR. At 2-years post-operatively the mean improvement in GMFM is 11.66%, improving to 12.35% at 5-years.

There were no significant complications.

CONCLUSIONS: SDR is an effective treatment for carefully selected patients with cerebral palsy with spasticity mainly affecting the legs. Multi-modal assessments demonstrate improvements that have been sustained over initial 5-year follow up.

Keywords: Selective dorsal rhizotomy (sdr), Spasticity, Cerebral palsy, Outcome, Quality of life

Nursing Symposium Abstracts

Freeze preservation of cranial bones after decompressive craniectomy for future cranioplasty. Our experience

Dulce Karolina Martinez Gonzalez¹, Oscar Guillermo Garcia Gonzalez²

¹Nursing department, Universidad Autonoma de Aguascalientes, Aguascalientes, México

²Department of Pediatric Neurosurgery, Hospital Regional de Alta Especialidad del Bajio, Leon Guanajuato, México

BACKGROUND AND AIM: Decompressive craniectomy is routinely performed to treat intracranial hypertension refractory to medical therapy as a result of head trauma, cerebrovascular accident (CVA) or brain tumors. It is later followed by a cranioplasty procedure (CP) in the surviving patients, with autologous bone graft or other reconstructive materials is considered to repair the skull defect.

This retospective study reviews the cases of decompressive craniectomies followed by later cranioplasty undertaken in the author experience since 2013 and describes the method used for preservation of removed bone flaps for future cranioplasty. To clarify the clinical outcomes of cranioplasty with cryopreserved bone flaps and identify risk factors related to bone flap infection and resorption after cranioplasty with cryopreserved bone flaps.

METHOD: 6 patients (5 children) underwent decompressive craniotomies and delayed autologous cranioplasty since 2013. A protocol was designed to prepare the removed bone flaps for freeze preservation. After removal, the bone flaps were transferred to the blood bank of our institution within 4 h, gently rinsed using 1–3 L of sterile saline (0.9% NaCl) supplemented with antibiotics (amikacyn), then flaps were wrapped in two layers of sterile plastic coverage and preserved at –25/28.7 °C.

RESULTS: The patient’s population will be presented. Since 2013 we have performed 6 cranioplasties using freeze preserved autologous bone graft. The median time from craniectomy to cranioplasty was 62.5 days. Up to now, no case of infection, osteomyelitis or complete bone resorption following cranioplasty have occurred.

CONCLUSIONS: Freeze preservation of autologous bone grafts to reconstruct skull defects after decompressive craniectomy is a useful procedure and has a low revision or complication rate and led to the unnecessary use of synthetic prostheses and increased health care costs.

Keywords: Freeze preservation, Bone flaps, Craniotomy

Moya Moya Disease- Case Study

Shani S D¹, Jayanand Sudhir B²

¹Neurosurgery I C U, S C T I M T

²Department of Neurosurgery, S C T I M S T

BACKGROUND AND AIM: Moyamoya disease is a rare disease which cause progressive narrowing of the intracranial internal carotid arteries, resulting in reduced blood supply to brain, leading to strokes. It is a major cause of childhood stroke.

METHOD: A 10-year- boy presented with recurrent left hemispheric transient ischemic attack and seizures. On evaluation, the child was diagnosed as having bilateral Moyamoya disease. The child was prescribed antiplatelets and antiepileptics and advised to drink 2 L of water a day and to avoid dehydration. He was admitted for an elective revascularization surgery. Left side Superficial Temporal Artery (STA) to Middle Cerebral Artery (MCA) bypass with Encephaloduroarteriomyosynangiosis (EDAMS) was done. The child was monitored in the post-operative neurosurgery intensive care unit for one day for any post procedure complications. Child was encouraged to talk and express preferences in diet, dress and play materials among the given alternatives. Ambulated out of bed after six hours. Allowed to walk around as preferred. Parents were allowed to visit and spend time with the child.

RESULTS: Post-operative course was uneventful and the child was discharged on 6th post-operative day with instruction to continue antiplatelets and antiseizure medications. The nursing care challenges included positioning in the post operative period, maintain invasive devices, providing child with a sense of control, understanding child’s preferences and promoting autonomy and intensive care unit policies regarding visiting hours and family presence. The patient should be monitored for seizure, stroke transient ischemic events and wound infection. Strict vigilance and adherence to infection control practices are necessary. Early ambulation and early initiation of feeds are done to prevent complications.

CONCLUSIONS: The outcome of cerebral revascularization in Moyamoya disease is good, with reduction in ischemic events and seizures. Post-operative nursing care in neuro surgery unit is important in preventing complications and better outcome.

Keywords: Moyamoya disease, Encephaloduroarteriomyosynangiosis, Revascularization surgery, Carotid arteries, STA-MCA bypass, Nursing care

Utilizing a Clinical Pathway For Coordination of Care of Infants with Myelomeningocele

Ashley Kelly Birch

Boston Children's Hospital, Boston, Massachusetts USA

BACKGROUND AND AIM: As of 2013, approximately 1.61 infants out of 10,000 live births were born in Massachusetts with spina bifida, an increasing number are being transferred to our NICU. Due to the medical complexities of infants with Spina Bifida, a standardized guideline to direct tcare was needed.

AIM:

• To discuss the need for coordination of care for infants born with myelomeningocele related to the medical complexities.

• To discuss the clinical pathway and orderset created as a result of a collaboration between Neurosurgery and the NICU.

METHOD:

• A review of the literature and existing protocols and pathways at Boston Childrens Hospital was performed prior to creation of the clinical pathway.

• Collaboration of the NICU and Neurosurgery to determine the needs of infants born with myelomeningocele immediately after birth and during the course of their admission.

• Review of the clinical pathway by the QI team and clinical pathway committee followed by Publication and Distribution.

RESULTS: • NICU and neurosurgery teams collaborate by using the pathway and orderset.

• Consultations are requested as part of the orderset and therefore routine health maintence and consultations required for infants with myelomeningocele are addressed early in course of treatment.

• Use of antibiotics and preop dressings have been standardized.

• The use of the clinical pathway offers clinical guidance and standardization for speciality clinicians based on evidence.

• Supports a seamless transition from the inpatient team to providers within the multidisciplinary clinic.

CONCLUSIONS: Due to the many medical complexities of infants with Spina Bifida, a standardized guideline to direct the management of care was needed. The complexities of care include management of the lesion, bladder management, bowel management, infection control, coordination of consultations and routine health maintence. Creating this streamlined approach did improve care for these patients by ensuring that the require consultations happened automatically, without long wait times and encouraged continuous collaboration of the specialties.

Keywords: Spina bifida, NICU, Pathway, Standardization, Nursing

Implementation of Multidisciplinary Spina Bifida Clinics in Low-and-Middle income Countries and the Important Role For Nurses in Maintaining Them

Ashley Kelly Birch

Boston Children's Hospital, Boston, Massachusetts USA

BACKGROUND AND AIM: Neural tube defects occur in approximately 300,000 neonates worldwide annually and are a leading cause of death and disability. They require frequent monitoring by neurosurgery, orthopedics, urology and physical therapy to maintain their quality of life and prevent illness. Due to the medical complexities of patients with Spina Bifida, the most comprehensive way to care for these children is through a multidisciplinary clinic which can provide coordination of care with nurses in a leadership role.

METHOD: A review of the literature was completed to accumulate all evidence regarding existing multidisciplinary clinics for patients with spina bifida globally.

• A review of the literature to establish the benefit of multidisciplinary clinics in care for patients with medical complexities, including spina bifida association and WHO recommendations.

• A review of the literature to establish the current utilization of nurses in existing clinics.

RESULTS: • A coordinator, such as a nurse coordinator allows for good communication and collaboration between the key providers.

• There has not been a consensus on what specialties should be included in these clinics in different socioeconomic settings.

• Access and integration of services are a main goal of multidisciplinary clinics, to allow for unfragmented essential care and improve outcomes.

CONCLUSIONS: • Due to the many medical complexities of infants with Spina Bifida, multidisciplinary clinics are needed, they increase access to care, decrease duplication of services, can reduce cost and improve outcomes.

• Care coordinators are a vital part of these clinics to allow for adequate coordination of care, this role can be filled by nurses.

• Establishment of standards for included specialties and services in various settings is required.

• In limited resource settings it is more difficult to establish these clinics, further research must be done to determine the needs in LMICs and recommendations on how to implement this method of care.

Keywords: Spina bifida, Multidisciplinary care, Nursing

Medical tourism in Pediatric Neurosurgery during the Covid pandemic: An observational study of a complex situation

Orna Friedman

Department of Pediatric Neurosurgery, Dana Children’s Hospital, Tel Aviv, Israel

During previous ISPN gathering, we have presented our nursing perspective of Medical Tourism (MT) in Pediatric Neurosurgery and coined it as “lost in translation..”

During Covid times, in addition to the local hospital chaos and uncertainty, it has become exceedingly rare to travel in general, and especially to receive medical care in another country.

These difficulties came from state (country) regulations, hospital protocols, and combined medical challenges (e.g. Covid in a child with a brain tumor).

Despite these enormous obstacles, we managed to bring and treat a significant number of children requiring neurosurgical care.

In this study, we systematically analyzed the steps that we needed to overcome from our perspective and from the perspective of the courageous families.

Planning intraoperative nursing assistance in the process of separation of craniopaguus siamese twins. An experience report

Allison Roberto Silva, Hélio Rubens Machado, Marcelo Volpon Santos

Department of Pediatric Neurosurgery, São Paulo University. Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, Brazil

INTRODUCTION: Siamese twins with anatomical conjugation by the head (craniopagus) are a rare condition in the history of medicine, only 28 attempts at separation in more than one stage were performed and of these, 03 successful cases occurred in Brazil. The multidisciplinary team for the separation of Craniópagus twins at HCFMRP-USP, takes on a new challenge in 2022 for the separation of craniopagus twins. OBJECTIVE: To describe the Nurse's activities for the planning of all stages and the performance of surgical procedures.

METHODOLOGY: This is an experience report, where the Nursing planning, the 3D simulations, the simulations in the operating room and the execution of the surgical steps of Craniopagus separation are performed.

RESULTS and DISCUSSION: The planning of the process is planned for five distinct surgical stages, the first stage of planning included the definition of the children's basic needs and the objectives of the surgical and clinical teams, which determined the Nursing Diagnoses and the necessary interventions to that the process becomes successful in its continuity. The following surgical steps will be planned using the first surgery as a support, as the staging is progressive and the evolution of children is concomitant.

CONCLUSION: For the separation process to be successful, nursing planning is essential, surgical simulations and clinical interventions for each stage will influence the final result and the children's recovery.

Keywords: Craniopagus twins, Pediatric Neurosurgery, Surgical nursing, Nursing planning

Surgical treatment of epilepsy in children, nursing assistance in building intraoperative excellence

Allison Roberto Silva, Hélio Rubens Machado, Marcelo Volpon Santos

Department of Pediatric Neurosurgery, São Paulo University. Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, Brazil

INTRODUCTION: Epilepsy is defined as a brain disorder characterized by a long-lasting predisposition to recurrent seizures and their consequences. For the most part, the treatment of choice is performed with the use of drugs that inhibit uncontrolled electrical discharges and when this does not achieve the desired effect, surgical treatments are considered. To guarantee excellence in these treatments, a multidisciplinary approach is necessary, the assistant nurse has a unique importance for this treatment to occur in the best possible way, ensuring safety and excellence in intraoperative care of children with epilepsy.

OBJECTIVES: To describe the activities of the Surgical Center nurse during the Epilepsy surgery process.

METHODS: This is an experience report, where aspects related to surgeries for the treatment of Epilepsy are addressed, as well as the main diagnoses and nursing interventions in children with surgical indication as the treatment of choice in this condition.

RESULTS and DISCUSSION: According to our experience, in a significant number of patients diagnosed with epilepsy during childhood, drug treatment does not have the desired effect. As a new perspective of coping, the Pediatric Neurosurgery team has available surgical techniques indicated for each patient individually. Thus, indications such as implantation of electrodes for monitoring and subsequent lesionectomy, partial or total lobectomies and implantation of vagus nerve stimulators (VNS) are options to be considered. In this context, nursing interventions reflect the care necessary for the treatment of patients based on the nursing diagnoses found, these are related to neurological, social interaction, cognitive, psychological and motor consequences.

CONCLUSION: The multidisciplinary interaction between Nursing and Pediatric Neurosurgery during the surgical process of children with Epilepsy, brings patients an expanded safety scope, where basic human needs are observed through two different prisms, obtaining greater safety in the process and quality assurance. in the procedure.

Keywords: Surgical nursing, Epilepsy, Pediatric neurosurgery, Pediatrics

An evaluative study to assess the outcome of neurorehabilitation among children's admitted in Neuro ICU king George hospital Visakhapatnam, Andhrapradesh, India

Purnima Pandrinki

Department of neurosurgery, andhra medical college king George hospital Visakhapatnam Andhrapradesh india

BACKGROUND AND AIM: The action of restoring someone to health or normal life through training and therapy after illness. The assessment begins with cognitive issues where is the child in the development spectrum, sensory issues need to be evaluated, are vision, hearing and other senses present and meeting the needs of the child. Starting rehabilitation as soon as a health condition is noted and continuing to deliver rehabilitation alongside other health interventions. Helps a child to be as independent as possible in everyday activities.

OBJECTIVES:

1. To assess the outcome of pediatric neuro rehabilitation among children's admitted in neuro icu kgh vsp.

2. To assess the effectiveness of rehabilitation in improving for a speedy recovery of children's admitted in neuro icu kgh vsp.

3. To help individual child to achieve the best best outcome.

4. To reduce the length of stay in hospitals.

5. To associate the demographic data with outcome of pediatric neuro rehabilitation.

METHOD: Sample size -30.

Sampling technique- simple random sampling technique.

Development of tool: consist of two sections.

Section A- demographic data.

Section B—questionnare on practice of rehabilitation.

An evaluation is done in all the pediatric cases admitted in the ICU with different diagnosis like trauma, rare MMC's in school going child, CCM and pediatric tumors and the need of rehabilitation for these children's have been identified and appropriate rehabilitation therapy was been given to the children's in the ICU.

RESULTS: Still working on it.

CONCLUSIONS: The need for pediatric neuro rehabilitation in the ICU was been recognised by the members of the health team and appropriate measures of therapies was been done and the outcome of speedy recovery was seen among the cases admitted in ICU. And also appropriate education was provided to the family members on the importance of rehabilitation.

Keywords: Rehabilitation, rspeedy recovery, hospital length of stay, impairme

List of posters presented at 48th ISPN Annual Meeting

Poster Session 1: Wednesday, December 7, 2022

Poster Number	Topic	Title	Presenter	Country
PP-001	Innovation and technology	Development and validation of a remote video acquisition and analysis protocol using artificial intelligence for evaluation of gait	Albert Tu	Canada
PP-002	Innovation and technology	Neurosurgery Cocktail -Its Impact on Neurosurgical Communication and Research	Bipin Chaurasia	Nepal
PP-003	Innovation and technology	Technical Note on Inside-Out Approach for Foramen Magnum Decompression in Children with Achondroplasia	Moise Danielpour	United States
PP-004	Innovation and technology	Brainstem Neuroenteric cyst: A novel management proposal	Chandrasekaran Kaliaperumal	United Kingdom
PP-005	Innovation and technology	Music Therapy as a peri-operative intervention in Paediatric Neurosurgical patients( MuPeNS-Study)	Chandrasekaran Kaliaperumal	United Kingdom
PP-006	Innovation and technology	Music Intervention for Paediatric peri-operative care: MuPeNS Study- Pilot feasibility study	Chandrasekaran Kaliaperumal	United Kingdom
PP-007	Innovation and technology	Novel intraoperative neurophysiological techniques to preserve brain connectivity during asleep surgery: Implications for Pediatric Neurosurgery	Francesco Sala	Italy
PP-008	Innovation and technology	Error in pediatric scoliosis curve measurement and the role of artificial intelligence and machine learning for accurate diagnosis: a pilot study from multi-institutional experience	Hasan Raza Syed	United States
PP-009	Innovation and technology	Clinical Applications of focused ultrasound in pediatric neurosurgery: novel management for pediatric brain tumors	Hasan Raza Syed	United States
PP-010	Innovation and technology	The evolution of Linear Accelerator Radiosurgery for Pediatric Central Nervous System lesions: The Hyperarc and OSMS	João Gabriel Ribeiro Gomes	Brazil
PP-011	Innovation and technology	Case report of vagal nerve stimulator dysfunction from a mechanical toy and literature review of toy-related programmable device dysfunction	Rebecca Chave Cox	United Kingdom
PP-012	Innovation and technology	Pediatric Neurosurgeons as Innovators: An Analysis of the Patents of North American Pediatric Neurosurgeons	Sandi Lam	United States
PP-013	Innovation and technology	Minimal invasive treatment of non-syndromal craniosynostosis	Thomas Hauser	Austria
PP-014	Innovation and technology	Gene therapy for pediatric neurologic diseases: New tools in neurosurgeon’s box to improve delivery	Timothée De Saint Denis	France
PP-015	Global Pediatric Neurosurgery	Giant Calcified Cephalohematoma Crossing the Sagittal Suture: A Systematic Review with Case Illustration, Modified Classification and Management Algorithm	Omar Aljohani	Saudi Arabia
PP-016	Moya-Moya disease	Identification of diagnostic biomarkers for pediatric Moyamoya disease based on plasma-derived extracellular vesicle miRNA	Eun Jung Koh	South Korea
PP-017	Hydrocephalus	Effect of on shunt survival of the biochemical and cellular properties of cerebrospinal fluid among patients following ventriculoperitoneal shunting	Benjamin Kasyoka Mutiso	Kenya
PP-018	Hydrocephalus	Pitfalls in diagnosis of shunt malfunction in children	Chandrasekaran Kaliaperumal	United Kingdom
PP-019	Hydrocephalus	Management guidelines for Long tunnelled Ventricular drain in paediatric brain tumour: a medical and nursing perspective	Chandrasekaran Kaliaperumal	United Kingdom
PP-020	Hydrocephalus	Neuroendoscopic Lavage in preterm infants with IVH	Christian Auer	Austria
PP-021	Hydrocephalus	The Role of Ventriculoperitoneal Shunt Placements in Palliative Care	Eylem Ocal	United States
PP-022	Hydrocephalus	Approaching hydrocephalus in pediatric posterior fossa tumors	Hsin Hung Chen	Taiwan
PP-023	Hydrocephalus	A 25 years experience of Endoscopic Third Ventriculostomy (ETV). – a single institute retrospective analysis actively introduced ETV in infantile obstructive hydrocephalus -	Kazuaki Shimoji	Japan
PP-024	Hydrocephalus	The management of hydrocephalus in median posterior fossa cystic collections: surgical outcome from a retrospective single-center series of 54 consecutive pediatric patients	Lelio Guida	France
PP-025	Hydrocephalus	Abdominal Pseudocysts with Children with Ventriculoperitoneal Shunts: A Systematic Review and Proposed Approach to Management	Melissa LoPresti	United States
PP-026	Hydrocephalus	Suggested Predictive Scoring System for Postresection Hydrocephalus in Pediatric Patients with Posterior Fossa Tumors	Noor Ul Huda Ul Maria	Pakistan
PP-027	Hydrocephalus	Proposed Predictive Scoring System for Postresection Hydrocephalus in Pediatric Patients with Posterior Fossa Tumors	Noor Ul Huda Ul Maria	Pakistan
PP-028	Hydrocephalus	Choroid Plexus endoscopic removal in children with hydrocephalus. Surgical technique and clinical outcome	Oscar Garcia González	Mexico
PP-029	Hydrocephalus	"Shunt site pain with calcified catheter and functioning VP shunt – to operate or not?"	Rehman Ali Baig	United Kingdom
PP-030	Hydrocephalus	Prevention of slit ventricle syndrome by the use of antisiphon devices in shunt-treated hydrocephalic children	Ryo Ando	Japan
PP-031	Hydrocephalus	Retrospective Study comparing Outcomes between Ultrasound-guided VP shunt insertion and Free-hand insertion	Shi Hui Ong	Singapore
PP-032	Hydrocephalus	Multiloculated hydrocephalus presenting as bobble doll head syndrome	Shighakolli Ramesh	India
PP-033	Hydrocephalus	Role of neuroendoscopy (rigid and flexible) in management of hydrocephalus: Our experience in last 5 years	Shighakolli Ramesh	India
PP-034	Hydrocephalus	Hydrocephalus associated with spinal dysraphism -which CSF diversion procedure is ideal ?	Supriya Chauhan	India
PP-035	Hydrocephalus	Hydrocephalus associated with spinal dysraphism- which CSF diversion is ideal?	Supriya Chauhan	India
PP-036	Hydrocephalus	Factors affecting the success of endoscopic third ventriculostomy in infective Hydrocephalus	Sushanta Kumar Sahoo	India
PP-037	Neuroendoscopy	Endoscopic Suturectomy in Sagittal Craniosynostosis Treatment: Preliminary Case Series in the Indonesian National Referral Hospital	Antari Rahmadani Harmani	Indonesia
PP-038	Neuroendoscopy	Endoscopic septostomy for post infectious multiloculated hydrocephalous to prevent multiple shunt surgeries in children – a case series	Apinderpreet Singh	India
PP-039	Neuroendoscopy	Technical Considerations in Flexible Endoscopic Biopsy of Pediatric Brain Tumors	Carolyn S Quinsey	United States
PP-040	Neuroendoscopy	Use of GOLD Laser in Endoscopic Third Ventriculostomies: Report of 30 Cases	David F Jimenez Md, Facs, Faans.	United States
PP-041	Neuroendoscopy	Complete monoportal fully endoscopic resection of pineal region tumour via the transchoroid approach	David Rowland	United Kingdom
PP-042	Neuroendoscopy	The role of CSF dynamics in the early morphological changes after endoscopy and helmet therapy for scaphocephaly	Federico Di Rocco	France
PP-043	Neuroendoscopy	Intracranial Neuroendoscopy in Children and Adults: A Comparative Analysis	Jehuda Soleman	Switzerland
PP-044	Neuroendoscopy	Trans Nasal Endoscopy in Paediatric Sella – Suprasellar Lesions – A Citadel for Varied Spectra Of Lesions, An Institutional Experience	Gowtham Matham	India
PP-045	Neuroendoscopy	Flexible endoscope assisted suture release (FEASR) and barrel stave osteotomy for the correction of sagittal synostosis	Jason Labuschagne	South Africa
PP-046	Neuroendoscopy	Endoscopic transorbital resection of a rare orbital alveolar soft part sarcoma in a 3-year old: a mimicker of haemangioma	Joyce Shuk Wan Chow	Hong Kong
PP-047	Neuroendoscopy	Neuroendoscopy in the Management of Pineal Region Tumours in Children	Chandrashekhar. E. Deopujari	India
PP-048	Neuroendoscopy	Neuroendoscopy and management of ruptured intracranial Sylvian arachnoid cysts	Luca Massimi	Italy
PP-049	Neuroendoscopy	Endoscopic Management of Lateral Ventricle Arachnoid Cysts – Case Series with Proposed Classification	Manas Panigrahi	India
PP-050	Neuroendoscopy	Ventricular Catheter Delivery Device in endoscopic procedures	Manas Panigrahi	India
PP-051	Neuro-Oncology	Pediatric oncology neurosurgery, four years after centralization in the Princess Máxima Center	Kirsten Van Baarsen	Netherlands
PP-052	Neuro-Oncology	Delay in the Diagnosis of Childhood Brain Tumours: Contributing Factors and Outcome A Systematic Review of the Literature	Kristy Kehoe	United Kingdom
PP-053	Neuro-Oncology	Case Report: Childhood Intracranial Lesion Associated with Tonsoku-like DNA repair protein (TONSL) Mutation - A novel finding	Kristy Kehoe	United Kingdom
PP-054	Neuro-Oncology	Paediatric Primary CNS Inflammatory Myofibroblastic Tumour: Two Cases of A Rare Paediatric Tumour	Lin Wei Ooi	Malaysia
PP-055	Neuro-Oncology	Primary leptomeningeal medulloblastoma: a case-based review	Maria Rosaria Scala	Italy
PP-056	Neuro-Oncology	Atypical ATRT With multiple Difusse lesions in posterior fossa and left Trigone	Mayra Arce Lozoya	Mexico
PP-057	Neuro-Oncology	Papillary craniopharyngioma in an 8-year-old girl with BRAF V600E mutation	Nivedh Dinesh	Singapore
PP-058	Neuro-Oncology	Management and outcomes of paediatric craniopharyngioma: A 15-year experience in Singapore	Rambert Wee	Singapore
PP-059	Neuro-Oncology	The COMBAT Project - Core post operative morbidity set for paediatric brain tumours	Sandhya Trichinopoly Krishna	United Kingdom
PP-060	Neuro-Oncology	Giant and rare cranial tumors in pediatrics – tips and tricks for successful Neurosurgical outcome	Saraj Kumar Singh	India
PP-061	Neuro-Oncology	Application of neuroendoscopy in surgery for prepontine epidermoid cyst of children	Sheng Che Chou	Taiwan
PP-062	Neuro-Oncology	Infantile Brainstem High Grade Glioma: A Case Report and Literature Review	Shi Hui Ong	Singapore
PP-063	Neuro-Oncology	The outcome of children with craniopharyngioma treated in multidisciplinary team	Sławomir Blamek	Poland
PP-064	Neuro-Oncology	Intraoperative MRI to improve accuracy of frameless biopsies in the pons	Sonia Tejada	Spain
PP-065	Neuro-Oncology	Predictive factors for the occurrence of peri-surgical complications in pediatric posterior fossa tumors	Stephanie Anetsberger	Switzerland
PP-066	Neuro-Oncology	Diffuse Leptomeningeal Glioneuronal Tumor of Childhood	Tatiana Protzenko	Brazil
PP-067	Neuro-Oncology	Intraspinal cervical chondromesenchymal hamartoma as a presentation of DICER1 Syndrome in a newborn	Victor Javier Fernández Cornejo	Spain
PP-068	Neuro-Oncology	Biopsy of paediatric brainstem intrinsic tumours: 10- year experience from a Singapore children’s hospital	Yuan Guang Lim	Singapore
PP-069	Neuro-Oncology	Extracranial metastases from high-grade gliomas	Yu-Cheng Chou	Taiwan
PP-070	Neurotrauma/Critical Care	Incidence of Shaken Baby Syndrome in Brazil public health over the last 6 years	Carolina Carmona Pinheiro Machado	Brazil
PP-071	Neurotrauma/Critical Care	Protocolized management of isolated linear skull fractures at a Level 1 pediatric trauma center	Christopher M Bonfield	United States
PP-072	Neurotrauma/Critical Care	Low Velocity Penetrating Injury Of The Central Nervous System in Children: A Report of Two Unusual Cases	Debajyoti Datta	India
PP-073	Neurotrauma/Critical Care	Epidemiology Of Pediatric Traumatic Brain Injuries - Our institutional experience, Andhra medical college, Visakhapatnam,India	Hema Swaroop Kurumella	India
PP-074	Neurotrauma/Critical Care	Global Epidemiology of Pediatric Traumatic Spinal Cord Injury: A Systematic Review and Meta-Analysis	Joseline Haizel Cobbina	United States
PP-075	Neurotrauma/Critical Care	The Role of Virtual Planning and Modified CAD/CAM Implants in Cranioplasty	Malte Ottenhausen	Germany
PP-076	Neurotrauma/Critical Care	Metabolic and microstructural changes in children with severe TBI. DTI and 1H MRS study	Maxim Ublinskiy	Russia
PP-077	Neurotrauma/Critical Care	Growing Skull Fractures - An Uncommon Cause of Seizures	Merry Francis Kallely	India
PP-078	Neurotrauma/Critical Care	Single Burr Hole Evacuation of Extradural Hematoma in Pediatric Population: An Experience from the biggest Children Hospital of Pakistan	Mian Awais	Pakistan
PP-079	Neurotrauma/Critical Care	Long term outcomes in pediatric cranioplasty post decompressive craniectomy	Tarunesh Sharma	India
PP-080	Neurotrauma/Critical Care	Pediatric retroclival hematomas: case series, systematic review, and a proposed novel approach for drainage	Yahya H. Khormi	Saudi Arabia
PP-081	Other	Knowledge, Attitude and Practices Related to Craniosynostosis Among Physicians in Saudi Arabia: "A Cross-Sectional Study"	Abdulrazaq Abdulmohsen Alojan	Saudi Arabia
PP-082	Other	Neurosurgical Management of Hydrocephalus and Cerebellar Tonsillar Herniation in the Megalencephaly-Capillary Malformation-Polymicrogyria Syndrome	Alon Kashanian	United States
PP-083	Other	Single Institution Feasibility Trial: Incorporating Pediatric Patient Reported Outcome Scales into Clinic Workflows	Ben S Succop Jr	United States
PP-084	Other	Development of pediatric neurosurgery in Mongolia	Byambatsend Byambaa Dorjsuren	Mongolia
PP-085	Other	Frontal Sinus Hypoplasia in Unoperated Older Patients with Craniosynostosis: A Pilot Study	Chris Bonfield	United States
PP-086	Other	Evaluating Caregiver Stress in Craniosynostosis Patients	Christopher M Bonfield	United States
PP-087	Other	Simple vaccum extractor treatment for ping pong skull depressed fractures	Mauricio Daniel Puch	Bolivia
PP-088	Other	Intraoperative Monitoring in Pygopagus Separation: What We Have Learned So Far	Nadya Zaragita	Indonesia
PP-089	Other	Imaging of Encephaloceles	Peter Kalina	United States
PP-090	Other	5 Years Follow up of Successful Craniopagus Separation	Setyo Budi Premiaji Widodo	Indonesia
PP-091	Other	A Case of Encephalocele which Developed Hydrocephalus After the First Surgical Repairment	Taekyun Kim	Japan
PP-092	Other	Muenke Syndrome - Unusual presentation	Tatiana Protzenko	Brazil
PP-094	Peripheral nerve	Dynamic Reanimation of Facial Paralysis in Children by using Masseteric Nerve	Anh Mai Bui	Vietnam
PP-095	Vascular	Our experience with pediatric vascular malformations	Dan Aurel Nica	Romania
PP-096	Vascular	De-novo Arteriovanous malformation in a 8 year old and Neurosurgical implication: Case report and literature review	Ieva Sataite	United Kingdom
PP-097	Vascular	Right side posterior interhemispheric transfalcine retrosplenial transprecuneus approach for the resection of bilateral periatrial cavernous malformation	Jose Ascencion Arenas Ruiz	Mexico
PP-098	Vascular	Arare case of mirror arteriovenous malformation	Suchanda Bhattacharjee	India
PP-099	Vascular	Ruptured ACA aneurysm in an infant with poor prognosis: case report and reviews of the literature	You Nam Chung	South Korea

Poster Session 2: Friday, December 9, 2022

Poster Number	Topic	Title	Presenter	Country
PP-100	Hydrocephalus	Treatment of myelomeningocele in Japan: Analysis of the medical claims database in Japan	Masahiro Nonaka	Japan
PP-101	Antenatal diagnosis and treatment	Developmental outcomes and peri-natal diagnosis of agenesis of the corpus callosum	Fareha Khalil	Ireland
PP-102	Antenatal diagnosis and treatment	Proposal of a protocol for assessment of motor development of children submitted to antenatal myelomeningocele repair	Renata Viana Brigido De Moura Jucá	Brazil
PP-103	Dysraphism	Neural Tube Defects cases in an Indonesian Industrial Area Referral Hospital during Covid-19 Pandemic	Andi Nugraha Sendjaja	Indonesia
PP-104	Dysraphism	Early Experience during COVID 19 Pandemic: Multidiciplinary Management of Lipomyelomeningocele	Astri Avianti	Indonesia
PP-105	Dysraphism	Congenital Midline Spinal Hamartoma in a 5-month-old Infant	Elric Brahm Malelak	Indonesia
PP-106	Dysraphism	New mutation in hereditary Dandy-Walker with occipital cephalocele	Frank Van Calenbergh	Belgium
PP-107	Dysraphism	Epidemiology of myelomeningocele- North coastal Andhra, India Genetic, Social,Economic,Environmental Factors affecting the occurrence	Hema Swaroop Kurumella	India
PP-108	Dysraphism	Preventive Strategy For Spinal Dysraphism - Pilot Project In North Andhra, India, Salt Fortification With Folic Acid	Hema Swaroop Kurumella	India
PP-109	Dysraphism	Supratentorial Anomalies in Spina Bifida	Ibrahim Alatas	Türkiye
PP-110	Dysraphism	Multidisciplinary Clinic for Closed Spinal Dysraphisms	Laura Grazia Valentini	Italy
PP-111	Dysraphism	Delayed Diagnosis of Cervical Dermal Sinus Tract in an Infant with Meningitis and Hydrocephalus	Mary Angeline Luz Ubias Hernandez	Philippines
PP-112	Dysraphism	The challenging treatment of a giant anterior meningoencephalocele in the newborn: About one case	Nabila Tighilt	Algeria
PP-113	Dysraphism	Surgical treatment of split cord malformation type I with scoliosis	Olga M Sergeenko	Russia
PP-114	Dysraphism	Fronto-ethmoido-nasal cephalocele in Bamako what surgical approach	Oumar Diallo	Mali
PP-115	Dysraphism	Spinal dysraphism:A way forward from our own experiences in treatment and prevention in LMIC’s	Prashanth Thalluri	India
PP-116	Dysraphism	Are prophylactic surgeries for lipomyelomeningoceles really prophylactic? A case of an asymptomatic lipomyelomeningocele with contradictory neurophysiology findings	Raenette David	United Kingdom
PP-117	Dysraphism	Incidence of neural tube defects in Bahrain	Taha Ali Alderazi	Bahrain
PP-118	Epilepsy	An ex vivo model to study fast ripple high-frequency oscillations detected by SEEG using dedicated surgical specimens from pediatric focal epilepsy patients	Adriano Cattani	Canada
PP-119	Epilepsy	Transitional Care for Epilepsy: A Systematic Review	Sandi Lam	United States
PP-120	Epilepsy	Seizure control after surgery of temporal lobe pathology: An Institutional experience	Suchanda Bhattacharjee	India
PP-121	Functional	Patient and Caregiver Reported Outcome Measures after Single-Level Selective Dorsal Rhizotomy in Pediatric Patients with Spastic Cerebral Palsy	Jehuda Soleman	Switzerland
PP-122	Functional	Microsurgical DREZotomy in spastic cerebral palsy: For a child with a little, a little is a lot	Nishant Goyal	India
PP-123	Germ Cell Tumors	Congenital intraventricular tumors: illustrative case and systematic review	Manilyn Ann Hong	Philippines
PP-124	Germ Cell Tumors	Porencephaly with Suprasellar Dermoid Cyst- A Novel Illustrative Report	Mitesh Karn	Nepal
PP-125	Germ Cell Tumors	A rare recurrent intramedullary immature teratoma, diagnostic and management dilemma: A case report and literature review	Tarunesh Sharma	India
PP-126	Global Pediatric Neurosurgery	High definition 2-D VITOM (Video Telescope Operating Monitor) assisted brain and spinal surgery in paediatrics: Is it an acceptable substitute for microscopic surgery?	Anand Kumar Das	India
PP-127	Global Pediatric Neurosurgery	Infantile macrocephaly: Complicated familial benign enlargement of subarachnoid space (BESS) in twins of suspected nonaccidental injury	Azam Ali Baig	United Kingdom
PP-128	Global Pediatric Neurosurgery	Craniosynostosis: A comparative analysis between surgical and clinical incidence in public health in Brazil	Carolina Carmona Pinheiro Machado	Brazil
PP-129	Global Pediatric Neurosurgery	Neurologist and Neurosurgeon: a ‘sine qua non’ in paediatric intracranial pathology management	Chandrasekaran Kaliaperumal	United Kingdom
PP-130	Global Pediatric Neurosurgery	Incidental Intracranial arachnoid cysts in the paediatric population- An institutional longitudinal review	Chandrasekhar Kaliaperumal	United Kingdom
PP-131	Global Pediatric Neurosurgery	Predictive outcome value of angular craniometry in surgical treatment of cerebellar tonsillar herniation	Federico Di Rocco	France
PP-132	Global Pediatric Neurosurgery	Transitional Care in Pediatric Brain Tumor Patients: A Systematic Literature Review	Jehuda Soleman	Switzerland
PP-133	Global Pediatric Neurosurgery	Vertebral and Costal Anomalies in Jarcho-Levin Syndrome: study of 121 cases	Ibrahim Alatas	Türkiye
PP-134	Global Pediatric Neurosurgery	Reddit users seek medical information for pediatric neurosurgery conditions online: a descriptive study	Jeffrey Steven Raskin	United States
PP-135	Global Pediatric Neurosurgery	Arachnoid cyst complicated by bleeding - case study	Magdalena Zgoda Aleksandrowicz	Poland
PP-136	Global Pediatric Neurosurgery	Negative pressure epidural syndrom,Causes of hemodynamic instability in children after Applying Negative Pressure to epidural Draining catheter after Craniotomy	Mohammad Sadegh Masoudi	Iran
PP-137	Global Pediatric Neurosurgery	Safety and Clinical Utility of Intraoperative cerebral angiography during surgery for paediatric arteriovenous malformations	Natasha Aziz	United Kingdom
PP-138	Global Pediatric Neurosurgery	Brain imaging to identify possible resectable brain lesion is vital when dealing with drug resistant epilepsy: incidental finding of a right peri-rolandic mass in a 15 years old boy with failed medical seizure treatment for years	Tee Tau Eric Nyam	Taiwan
PP-139	Infection	The Impact of Shunt Protocol on Reducing the Infection Rate Following Shunt Placement: "A Single Institutional Experience in Saudi Arabia"	Abdulrazaq Abdulmohsen Alojan	Saudi Arabia
PP-140	Infection	The Association Between Procalcitonin Level In Children With Ventriculitis In Rural Hospital In Medan Year 2020-2021	Abdurrahman Mouza	Indonesia
PP-141	Infection	Use of non enhanced MRI for follow up of intracranial infections using diffusion weighted sequence	Alya Hasan	Kuwait
PP-142	Infection	Causal Inference of Infectious Diseases on Hydrocephalus	Andrew T Hale	United States
PP-143	Infection	Intracranial empyemas in the COVID-19 era: a new pandemic? A paediatric case series and review of the literature	Benjamin J. Hall	United Kingdom
PP-144	Infection	Global Epidemiology of Central Nervous System Infections in Pediatric Patients: A Systematic Review and Meta-Analysis	Joseline Haizel Cobbina	United States
PP-145	Infection	Comparison of Outcome in Neurosurgically Treated Pediatric Subdural Empyema with or without Simultaneous Source Control Surgery	Ladina Greuter	United Kingdom
PP-146	Infection	Management of subdural empyemas	Rajeev Kariyattil	Oman
PP-147	Neuroendoscopy	Pure endoscopic treatment for Sylvian arachnoid cysts	Oscar Garcia González	Mexico
PP-148	Neuroendoscopy	Endoscopic third ventriculostomy with choroid plexus cauterization in treating infantile hydrocephalus: an experience from Mali	Oumar Diallo	Mali
PP-149	Neuroendoscopy	Endoscopic ultrasonic aspiration as alternative to more invasive surgery in initial management of optic pathway gliomas in children	Maria Rosaria Scala	Italy
PP-150	Neuro-Oncology	Frameless stereotactic biopsy for Midline lesions of the brain in Pediatric population	Abhinith Shashidhar	India
PP-151	Neuro-Oncology	The elusive clinical behavior of low grade glioneural tumors	Adrian Caceres	Costa Rica
PP-152	Neuro-Oncology	Cranial vault pediatric tumors: different technique to ensure total removal	Cecilia Casali	Italy
PP-153	Neuro-Oncology	Posterior fossa pilocytic astrocytoma contributing to paedaitric obstructive sleep apnoea: A case report and review of literature	Chandrasekaran Kaliaperuma	United Kingdom
PP-154	Neuro-Oncology	A 5-year outcome of Propranolol for the treatment of paediatric intracranial cavernoma: Case report and a review of the literature	Chandrasekaran Kaliaperumal	United Kingdom
PP-155	Neuro-Oncology	Survival Outcomes of Primary CNS Brain Tumours in Children: a single-centred retrospective observational study	Chandrasekaran Kaliaperumal	United Kingdom
PP-156	Neuro-Oncology	A rare presentation of a bilateral intracranial Parameningeal Embryonal Rhabdomyosarcoma in a 2-year-old child which mimicked Vestibular Schwannoma: a case report	Chandrasekaran Kaliaperumal	United Kingdom
PP-157	Neuro-Oncology	Pediatric Brain Tumour: A Study of One-year Data from a Tertiary Neurosurgical Centre, Myanmar	Ei Ei Khaing	Myanmar
PP-158	Neuro-Oncology	Case report of EBV associated smooth muscle intracranial tumour in a child	Felicia Hui Zhuang Chua	Singapore
PP-159	Neuro-Oncology	Choroid plexus papillomas in the first year of life: The value of pre-operative embolization and the interpretation of leptomeningeal enhancement in atypical tumors	Franceso Sala	Italy
PP-160	Neuro-Oncology	Trends in Pediatric Brain Tumor Incidence in Dr. Sardjito General Hospital, Yogyakarta, Indonesia, from 2020 – 2022	Handoyo Pramusinto	Indonesia
PP-161	Neuro-Oncology	Outcomes in surgical management of Craniopharyngiomas in pediatric age group at a high volume tertiary referral centre in India	Harshal Nandlal Agrawal	India
PP-162	Neuro-Oncology	Second-look surgery for pineal region tumors	Hideki Ogiwara	Japan
PP-163	Neuro-Oncology	Comparison of clinical features and treatment outcomes of pilocytic astrocytoma in pediatric and adult patients	Joo Whan Kim	South Korea
PP-164	Neuro-Oncology	Central Nervous System Tumor in Children. The Cuban Experience	Julio S. Brossard Alejo	Cuba
PP-165	Neuro-Oncology	Intratumoral bleed in pediatric primary spinal intradural Ewing’s sarcoma presenting with acute neurological decline	Karthigeyan Madhivanan	India
PP-166	Neuro-Oncology	Place of neo/adjuvant chemotherapy and limited surgery in the treatment of non-metastatic childhood medulloblastoma	Kévin Beccaria	France
PP-167	Occult tethered cord	Tethered cord diagnosis by MRI in supine and prone children positioning	Cordula Scherer	Switzerland
PP-168	Occult tethered cord	Posttubercular Arachnoid Cyst and Syringomyelia with Severe Spastic Paraplegia: case report and review of literature	Hsin Hung Chen	Taiwan
PP-169	Occult tethered cord	Elucidate surgical treatment criterias in tethered cord syndrome in patients with myelomeningocele	Ibrahim Alatas	Turkey
PP-170	Occult tethered cord	Sudden deterioration in previously undiagnosed occult dysraphism	Luca Massimi	Italy
PP-171	Occult tethered cord	Cervical spine dermal sinus tract in children	Pi Doanh Ngoc Nguyen	Vietnam
PP-172	Other	Squamosal Suture Synostosis and Hydrocephalus: A Minor Suture with Major Implications	Daphne Li	United States
PP-173	Other	Early Bone Reformation after Cranial Vault Remodelling for Sagittal Craniosynostosis	Elie Hammam	Australia
PP-174	Other	Surgical Drain Induced Subgaleal Hematomas and Skin Necrosis in Pediatrics: a Case Report	Gigih Aditya Wardana	Indonesia
PP-175	Other	A pediatric case of an intradiploic epidermoid cyst with cranial bone invasion	Hema Swaroop Kurumella	India
PP-176	Other	Pragmatism in Pediatric Neurosurgery: A Systematic Literature Review and Analysis	Jochem Spoor	Netherlands
PP-177	Other	Long-term results of minimally invasive strip craniectomy without helmet therapy for scaphocephaly - a single-center experience	Katharina Lutz	Switzerland
PP-178	Other	Skull Base and Craniocervical Junction Abnormalities in Patients with Crouzon Syndrome	Kerrin Sunshine	United States
PP-179	Other	Neurosurgical Treatment and Outcome of Pediatric Skull Base Lesions: A Case Series and Systematic Review of the Literature	Ladina Greuter	Switzerland
PP-180	Other	Craniosynostosis in primary metabolic bone disorders: a 10-year single institution experience	Maria A. Punchak	United States
PP-181	Other	Clinical variety and prognosis of arachnoid cysts in children	Martina Messing Jünger	Germany
PP-182	Other	MR exams under drug-free sedation with fixation device	Masahiro Kameda	Japan
PP-183	Spine	Laminotomy in Pediatric Spinal Surgery	Abraham Ibarra De La Torre	Mexico
PP-184	Spine	Transverse Split Laminoplasty: A Novel Anatomy Preserving Technique with Long Term Follow-Up	Daphne Li	United States
PP-185	Spine	Assesment of Vertebral Anomalies in Spina Bifida Patients: study of 422 cases	Ibrahim Alatas	Türkiye
PP-186	Spine	Split laminotomy approach for multilevel spinal cord tumors	Jose Ascencion Arenas Ruiz	Mexico
PP-187	Spine	Posterior ‘hemi-arch’ synchondral fracture of the atlas following penetrating neck injury in a child	Karthigeyan Madhivanan	India
PP-188	Spine	Clear cell meningioma of the cauda equina in a pediatric patient: a case report	Llex Chong Soriano	Philippines
PP-189	Spine	Surgical tactics in rare forms of aneurysmal bone cysts spine and skull bones in children	Pavel Lobankin	Russia
PP-190	Spine	Children with idiopathic syringomyelia presenting with back pain treated with lumbar punctures, a review of the last 11 years	Stuart Sinclair Stokes	United Kingdom
PP-191	Spine	Chronic recurrent multifocal osteomyelitis - a challenging diagnosis	Tatiana Protzenko	Brazil
PP-192	Spine	EOS Modulable Halo Brace: the present of Halo Vest	Timothée De Saint Denis	France
PP-193	Spine	Pediatric Tuberculous Spondylitis Surgery Using Adult Cervical Spine System In Limited Resources	Vira Dwi Nisrina	Indonesia