In vitro assessment of vascular injury following stent retriever retraction in clinically-relevant endothelialized silicone models.

Mechanical thrombectomy devices have potential to injure the vessel during treatment of acute ischemic stroke. The goal of the current work was to tailor in vitro endothelialized silicone models for stent retriever assessment and to evaluate endothelial injury following treatment by various stent retriever designs and sizes. Clinically-relevant neurovascular geometries were first modeled out of silicone, then sterilized, coated with fibronectin, placed in bioreactors, seeded with human endothelial cells, and cultivated under flow. Several sizes of two different commercially available stent retrievers were then deployed in, and retracted through, vessels. Vessels were immediately harvested and stained. Endothelial injury, identified as denudation, was quantified using ImageJ. Results illustrated that endothelial injury ranged from 16-18% in wire/microcatheter-only treated vessels, 37-61% in 1-pass treatments, and 52-70% in 2-pass treatments. Overall this work showcases an in vitro approach for early stage assessment of the extent and location of vascular injury following stent retriever retraction.