The influence of flow diverter's angle of curvature across the aneurysm neck on its haemodynamics

Flow diverter stents have provided a new method of endovascular reconstruction for large and complex aneurysms. Understanding the impact of the flow diverters angle of curvature across the neck and its metal coverage rate on the haemodynamics of aneurysm is crucial to maximize the mass flow reduction inside the aneurysm, post-deployment. The aim of this study is to understand the correlation between the angle of curvature of flow diverter across the aneurysm neck and the metal coverage rate, and the aneurysms haemodynamics, using computational fluid dynamics. Varying the flow diverter angle resulted in varying metal coverage rate across the aneurysm neck for two patient vessel geometries, A (straight artery) and B (curved artery) with aspect ratios of 3.1 and 2.9, respectively. The results indicate that there exists a relationship between the aneurysms haemodynamics and the flow diverters angle of curvature across its neck. Moreover, the calculations indicated that cases with a moderately curved flow diverter, with an associated metal coverage rate of 50%-60%, achieve maximum flow reduction inside the aneurysm due to a stable flow resistance in the direction normal to the blood flow.