The Hemodynamic Effect of Flow Diverter Treatment of Intracranial Bifurcation Aneurysms

Abstract

Flow diverter (FD) is a novel technique used for intracranial aneurysms, but the hemodynamic changes caused by FD implantation in bifurcation aneurysms (BAs) are still undefined. Computational fluid dynamics (CFD) were applied to analyze the hemodynamic parameters in a patient-specific basilar artery tip aneurysmal model, which include blood flow velocity, wall shear stress (WSS), aneurysmal wall pressure and branch vessel flow rate. The porous media model was used to simulate three different FD implantation strategies: single FD in a larger branch, single FD in a smaller branch and Y-shaped FD into bilateral branches. The flow velocity inside the aneurysmal sac was decreased by 70.99%, 76.13%, and 69.30% in strategies 1, 2 and 3, respectively. The mean WSS was decreased by 71.9% in Strategy 1, 73.9% in Strategy 2 and 76.1% in Strategy 3. The aneurismal wall pressure was dropped by 8.2% and 7.9% in Strategies 2 and 3, while the pressure was increased by 14.2% in Strategy 1. The velocity of the two small covered branches was dropped by 99.3% and 99.1% in Strategy 1, 10.3% and 7.5% in Strategy 2, and 15.2% and 6.3% in Strategy 3. The porous media model was considered feasible to simulate the implantation strategies of FD in BAs. The reduction velocity and WSS were observed in all FD implantation strategies, indicating the effectiveness of FD treatment in BAs. The blood flow of small covered branch vessels was decreased after FD implantation, suggesting potential risk of occlusion.