A Method to Evaluate Vessel Deviation during Withdrawal of a Stent Retriever Using a Silicon Vascular Model

Objective: Catastrophic complications may develop because of vessel deviation during device delivery into intracranial vessels for neurointerventions. We report a novel method using a silicon model capable of evaluating vessel deviation as a numerical value. Methods: In all, 10 tiny markers, each with a pitch of approximately 5 mm, were attached to the vessel model along the long axis. We used a high-resolution camera to record movies of the deviation of the vessel model while employing different stent retrievers. The movies were reviewed to determine the maximum deviation of each marker on the vessel model. Results: As expected, stent retrievers of the same type exhibited more vessel shifts when they had a larger diameter and longer length. On the other hand, stents with a segmental structure demonstrated less vessel deviation than those with a tubular structure, regardless of the large lumen and long length. Conclusion: If the degree of vessel stress can be represented by a numerical value, areas where the careful use of different devices for neurointerventions is required may be able to be identified. Moreover, this method may be useful for training.