A Novel Helical Thin-Film Flow Diverter: Design, Fabrication, and Computational Assessment of Hemodynamic Performance

Abstract

Flow diversion has become a key treatment modality for selected intracranial aneurysms, relying on the principle that a dense mesh of stent wires disrupts blood flow into the aneurysm sac, promoting thrombosis and vessel reconstruction. Despite its clinical success, a subset of patients experiences incomplete occlusion or complications. This study investigates innovative helical thin-film implants (HTFIs), aiming to evaluate their flow-diverting efficacy. Highly resolved computational fluid dynamics simulations were performed on two representative patient-specific aneurysm models. Two HTFI design variants were tested at various configurations (two rolling angles and three deployment positions). A total of 28 unsteady hemodynamic simulations were performed, comparing six hemodynamically relevant parameters against the pre-interventional state and a conventional braided flow diverter. The HTFIs induced significant changes in intra-aneurysmal flow. Both designs performed similarly overall, with the shorter configurations (smaller rolling angle) demonstrating superior efficacy. These achieved average hemodynamic reductions of 52.2% and 58.4%, outperforming the benchmark braided flow diverter device (47.4%). Sensitivity to positioning was modest, with the best configuration showing an average variation of only 5.3%, suggesting good robustness despite the helical design's heterogeneous porosity. These findings indicate that HTFIs offer promising flow-diverting capabilities. With further refinement in design and hemodynamic optimization, these implants hold potential as a next-generation alternative for the endovascular treatment of intracranial aneurysms, especially in applications requiring compatibility with smaller delivery systems.