Effect of VER on Blood Flow Velocity in Intracranial Aneurysms Treated by Coil Embolization using CFD

In coil embolization of intracranial aneurysms, the volume embolization rate (VER) of coils is commonly regarded as a predictor of aneurysm recanalization. However, there is limited research investigating the correlation between VER and hemodynamics across a diverse patient population using computational fluid dynamics (CFD). In this study, we assessed the impact of VER on the blood velocity in aneurysms using CFD analysis with varying VER. We included 31 cases of basilar-tip aneurysms treated with coil embolization. By employing a porous media model to simulate the embolized coil mass, CFD analysis was conducted with varying the simulated VER from 5% to 40% in 5% increments. The reduction ratio of velocity (RRV) in the aneurysm due to coil deployment was calculated. Our findings indicated that RRV exhibited a monotonically increasing trend with escalating VER, particularly showing a rapid ascent up to 90%. In most cases, a VER of 20-25% sufficed to achieve a 90% RRV; however, some cases demonstrated 90% RRV with exceptionally high or low VER. Basilar-tip aneurysms with a larger diameter of the PCA suggested the need for a higher VER to achieve sufficient blood flow reduction.