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Silicone models as basic training and research aid in endovascular neurointervention—a single-center experience and review of the literature

Abstract

The rapid development and wider use of neurointerventional procedures have increased the demand for a comprehensive training program for the trainees, in order to safely and efficiently perform these procedures. Artificial vascular models are one of the dynamic ways to train the new generation of neurointerventionists to acquire the basic skills of material handling, tool manipulation through the vasculature, and development of hand-eye coordination. Herein, the authors present their experience regarding a long-established training program and review the available literature on the advantages and disadvantages of vascular silicone model training. Additionally, they present the current research applications of silicone replicas in the neurointerventional arena.

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The authors have no personal financial interest in any of the materials or devices described in this article.

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Correspondence to Gerasimos Baltsavias.

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Matthew Gounis, Worcester, USA

The article entitled “Silicone models as basic training and research aid in endovascular neurointervention—a single-center experience and review of the literature” by Srinivasan Paramasivam and colleagues describes the utility of silicone cerebrovascular replicas for training in endovascular techniques. Over the past decade, advances in 3D modeling and rapid prototyping have enabled a generation of anatomically accurate cerebrovascular models. This review is timely, as it emphasizes the need to develop solutions for comprehensive training as the dramatic increase in the availability of specialized interventional programs has subsequently decreased the volume available for endovascular training at academic medical centers [1]. The authors have trained an impressive 178 fellows in basic neurointerventional techniques using these silicone models. Moreover, the paper describes the necessity for advanced training of experienced interventionalists with new technology, namely, imaging systems and medical devices.

Numerous research studies that have advanced technology in neuroendovascular treatments using silicone vascular replicas are surveyed in this paper. The advantages of these models include reproducible engineering studies on hemodynamics and device characterization. Due to costs and societal sensitivities associated with animal experimentation, these models provide a viable alternative to address certain important questions in research of interventional neuroradiology. Researchers have seeded 3D vascular silicone models with endothelial cells [2], making a new generation of replicas that can serve as bioreactors. Yet other groups are working on new materials to generate vascular replicas that offer nearly identical tactile feedback with respect to the human cerebrovasculature. Advances in vascular replicas will continue to advance the discovery of improved technology for the treatment of cerebrovascular disease and offer enriching training programs for the foreseeable future.

Shahram Majidi, Washington, USA

This is an important study stressing the role of silicone models as a training aid in endovascular neurointerventional fellowship training. Paramasivam et al provided their experience in using silicone models as training tools in their endovascular neurointerventional fellowship program. The authors have more than 15 years of experience in training fellows in the field of endovascular surgical neurology and have trained more than 170 fellows. According to their experience, using silicone models has had significant impact on expanding fellows’ skills in handling and manipulating and navigating microcatheter and guidewire and also performing procedures such as coil embolization with or without stent assistance. As the authors nicely outlined, silicone models can be also used as valuable research tools. For instance, we can design and execute complex experiments investigating the hemodynamic changes within the aneurysm following stent deployment or compare different clot-retrieving devices in a safe in vitro setting without risk of harming the patient. These sorts of experiments are essential components of the field considering the fact that not all the hemodynamic and biophysical aspects of the devices are fully understood.

Current guidelines recommend minimum procedural volume requirements in order to reach acceptable operator experience and proficiency in performing endovascular procedures [3, 4]. For example, this number is 30 procedures for aneurysm coil embolization. There are very few teaching institutions in the USA which meet minimum requirements for all the procedures needed to reach adequate operator experience [5]. Therefore, it is essential to use adjunct training modalities such as silicone models or computer simulators in order to help the trainees obtain and maintain adequate procedural skills. Computer simulators have been used as a valuable adjunct training modality for endovascular procedure training with proven impact on trainees’ skill improvement [6]. Similarly, Dr. Paramasivam’s study is a successful example of necessity and value of using silicone models in neurointerventional fellowship training.

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4. Connors JJ, 3rd, Sacks D, Furlan AJ, et al. Training, competency, and credentialing standards for diagnostic cervicocerebral angiography, carotid stenting, and cerebrovascular intervention: a joint statement from the American Academy of Neurology, the American Association of Neurological Surgeons, the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, the Congress of Neurological Surgeons, the AANS/CNS Cerebrovascular Section, and the Society of Interventional Radiology. Journal of vascular and interventional radiology : JVIR. Jul 2009;20(7 Suppl):S292–301.

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Paramasivam, S., Baltsavias, G., Psatha, E. et al. Silicone models as basic training and research aid in endovascular neurointervention—a single-center experience and review of the literature. Neurosurg Rev 37, 331–337 (2014). https://doi.org/10.1007/s10143-014-0518-x

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  • DOI: https://doi.org/10.1007/s10143-014-0518-x

Keywords

  • Silicone models
  • Training
  • Research
  • Endovascular neurointervention