Surgical Treatment in Symptomatic Chiari Malformation Type I: A Series of 25 Adult Patients Treated with Cerebellar Tonsil Shrinkage

  • Alessandro Villa
  • Alessia Imperato
  • Rosario Maugeri
  • Massimiliano Visocchi
  • Domenico Gerardo Iacopino
  • Natale Francaviglia
Part of the Acta Neurochirurgica Supplement book series (NEUROCHIRURGICA, volume 125)


Background: The variety of symptoms and radiological findings in patients with Chiari malformation type I makes both the indication for surgery and the technical modality controversial. We report our 5-year experience, describing our technique and critically evaluating the clinical results.

Methods: Between 2012 and 2016, 25 patients (15 female and 10 male; mean age 39.2 years) underwent posterior fossa decompression for Chiari malformation type I. Their clinical complaints included headache, nuchalgia, upper limb weakness or numbness, instability, dizziness and diplopia. Syringomyelia was present in 12 patients (48%). Suboccipital craniectomy was completed in all cases with C1 laminectomy and shrinkage of the cerebellar tonsils by bipolar coagulation; duraplasty was performed with a suturable dura substitute.

Results: Gratifying results were observed in our series. Symptoms and signs were resolved in 52% of patients, and 20% of patients had an improvement in their preoperative deficits. The symptoms of six patients (24%) were essentially unchanged, and one patient (4%) deteriorated despite undergoing surgery. Generally, patients with syringomyelia on magnetic resonance imaging (MRI) showed less symptomatic improvement after surgery. The syrinx disappeared in seven of 12 patients, and complications occurred in three patients (12%).

Conclusion: Cerebellar tonsil reduction and restoration of cerebrospinal fluid (CSF) circulation provided clinical improvement and a stable reduction in the syrinx size in the vast majority of treated patients, with a low rate of complications.


Chiari malformation type I Posterior fossa decompression Cerebellar tonsil shrinkage Syringomyelia Duraplasty 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Alessandro Villa
    • 1
  • Alessia Imperato
    • 2
  • Rosario Maugeri
    • 3
  • Massimiliano Visocchi
    • 4
  • Domenico Gerardo Iacopino
    • 3
  • Natale Francaviglia
    • 1
  1. 1.Division of NeurosurgeryARNAS Civico HospitalPalermoItaly
  2. 2.Division of NeurosurgeryIRCCS NeuromedPozzilliItaly
  3. 3.Neurosurgical Clinic, Department of Experimental Biomedicine and Clinical Neurosciences, School of MedicineUniversity of PalermoPalermoItaly
  4. 4.Institute of NeurosurgeryCatholic University of RomeRomeItaly

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