Abstract TP214: In-Silico versus In-Vitro Evaluation of a New Stent-Retriever Design: A Novel Approach to Pre-Clinical Device Development

Abstract

Introduction: In-vitro evaluation (analysis in a bench top flow model) is the gold standard for pre-clinical investigation of devices being developed for endovascular thrombectomy (EVT). In-silico evaluation (computer simulated analysis in a virtual stroke model) has the potential to test and optimize large number of stent-retriever design variations in a relatively time and cost-effective manner. We aim to validate the utility of in-silico evaluation when compared with in-vitro evaluation for the SuperNova Stent-retriever. Methods: In-silico analysis was performed using a virtual thrombectomy model, built using data from a fine-grained finite-element model, to estimate the probability of successful recanalization. Neurovascular anatomy of the virtual model was built based on digital subtraction angiography of an in-vitro model (Sim Agility, Mentice, Inc). Gravity Medical Technology’s SuperNova Stent-retriever was the device under investigation. Multiple thrombectomy scenarios were defined and validation analysis was performed. Results: We defined multiple thrombectomy scenarios including 1 cm red blood clot in M1 artery, 2 cm bifurcation M1-M2 red blood clot (Y-shaped clot), 1 cm white blood clot in M1 artery, and 1 cm white blood clot in superior M2 artery. The figure below demonstrates a pictorial representation of the first scenario- 1 cm red blood clot in M1 artery followed by mechanical thrombectomy simulation using the SuperNova stent-retriever. Per our in-vitro analysis (10 thrombectomy experiments), the rate of first pass effect and the rate of complete recanalization after a maximum of 3 passes using SuperNova stent-retriever was 50% and 90%, respectively. Preliminary data suggests 97% concordance. Conclusion: In-silico analysis has the potential to improve and expedite pre-clinical thrombectomy device development. Further studies are required to better understand the scope and potential of this technology.