Translational Research in Action: Development of Training Phantoms for Cerebrovascular Simulation

By May 16, 2019 Health, MedEd

Jonathan J. Stone, MD, MSe (left)
Assistant Professor of Neurosurgery at the University of Rochester Medical Center (URMC)
CEO of Simulated Inanimate Models (SIM), LLC

Michael P. Wilson, PhD (right)
Research Scientist and the COO of Simulated Inanimate Models (SIM), LLC

Many neurosurgical training programs are increasingly incorporating simulation to enhance resident and attending education. Several factors have led to this change in surgical education and training:

  • Work-hour restrictions decrease residents’ exposure to surgical cases;
  • A nationwide focus on the quality of health care delivery; and  
  • Societal expectations for surgical trainees to practice and learn in a manner that limits risk to the patient.

The need for safe, effective training tools is especially evident for new technologies, such as minimally invasive cranial neurosurgery. Many new minimal-access, image-guided methods may benefit from realistic simulation; this can allow not only risk-free training but also may provide a novel means for efficacy assessment of new devices.

There has been a surge of novel devices for the treatment of intracranial cerebral hemorrhage (ICH). These devices were borne out of the need to combat the historically poor clinical outcomes of ICH. While improvements in patient length of stay or other particular measures have been demonstrated, questions about the efficacy of the overall approach remain, and adoption rates of this technology remain low. Not unexpectedly, more recent evidence suggests that for minimally invasive ICH evacuation, clinical outcomes appear to correlate with surgeon experience. Realistic simulation, including lifelike physical phantoms, has the potential to increase surgeon competency and directly improve patient outcomes.

While surgical phantom-based simulation is a logical education method, there are no readily available training platforms for neurosurgery. Using advances in 3D printing and polymer chemistry, our lab developed technology at the University of Rochester Medical Center to create full procedural hydrogel training phantoms with realistic material properties.

Our lab began to collaborate with Dr. Tarun Bhalla, the Director of Stroke and Cerebrovascular Services, in efforts to construct a physical training phantom that enabled lifelike simulation of ICH evacuation. Materials research and an iterative creative process allowed for the creation of synthetic materials that not only resembled crosslinked blood clot but behaved as such when evacuated with traditional and minimally invasive aspiration devices. Our lab focused on enabling full procedural simulation by including as many realistic features as possible, including dura mater, venous sinuses, synthetic bone that handles a perforator drill bit, accurate CT imaging, and an exterior scalp that can be registered to image guidance. The resulting physical phantom can simulate the operative procedure, including all pre-operative planning, stereotactic navigation, initial approach, ICH evacuation, and complication management.

For an educational tool to be effective, the trainee must have their mindset as close as possible to a real-life scenario not only to mimic the sequential decision making but also create an element of familiarity for troubleshooting while still in a zero-risk scenario.

These phantoms were initially tested within URMC with the goal of providing effective training for minimally invasive techniques for both residents and experienced surgeons. In order to translate this technology and make it available to surgeons throughout the country, the technology was licensed to a small business that could scale manufacturing of these models. In collaboration with Dr. Christopher Kellner from Mount Sinai Health System, several training workshops have been held, and feedback from other surgeons has been positive, with most clinicians agreeing the phantoms provided a realistic training experience and lifelike demonstration. The ICH phantoms were recently featured at a Technology Innovation Showcase at the AANS/CNS Joint Cerebrovascular Section Annual Meeting. This event demonstrated the power of surgical phantoms to permit live demonstration of several different medical devices, highlighting function, value and safe use.

Not resting on the achievements above we are working on expanding the set of training tools to create physical models for other cerebrovascular neurosurgery procedures. Our lab is currently creating simulations for aneurysm clipping, direct bypass, endovascular embolization, and embolectomy. Continued innovation in cerebrovascular surgical simulations is needed in order shift the learning curve for new devices and techniques so that both novice and experienced trainees can learn on validated, realistic models and ultimately improve patient outcomes.

Editor’s Note:  Dr. Jonathan J. Stone and Dr. Michael P. Wilson hold equity in Simulated Inanimate Models LLC

We encourage everyone to join the conversation online by using the hashtag #VascularNeurosurgery.

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