Thin-Film Patient-Specific Flow Diverter Stents for the Treatment of Intracranial Aneurysms

Abstract

Intracranial aneurysm treatment based on blood flow reduction with braided flow diverters (FDs) has become highly relevant. However, FDs have several limitations, e.g., sudden torsional collapse, variable porosity, and possible side branch occlusions. Thin-film FD stents can overcome these limitations by offering high design freedom to produce patient-specific implants. Here a workflow to design, fabricate, and characterize novel thin-film FDs that can be individualized to meet patient-specific needs is demonstrated. FD design is virtually optimized to achieve the best flow reduction and the lowest crimping resistance. Then, the optimal design is fabricated using state-of-the-art thin-film technology. The thin-film FD is characterized for mechanical and flow behavior and is compared to a braided FD (Derivo; FD0). The thin-film FD and FD0 show similar radial forces in the diameter range 2.6–4.5 mm, and the former exhibits no sudden torsional collapse. The flow analysis using MRI reveals that both FDs reduce the flow into the aneurysm. However, only the thin-film FD maintains adequate flow into all the side branches. A thin-film FD that overcomes braided FDs limitations while offering similar performance has been developed. The proposed framework is a pilot study for fabricating on-demand patient-specific thin-film FD stents.