Influence of Shape on Saccular Aneurysm Hemodynamics and Risk of Rupture

Although the mechanisms of the formation, growth and rupture of aneurysms are not fully understood, hemodynamic forces play an important role. Computational fluid dynamics (CFD) software can be used to determine velocity and pressure fields within saccular aneurysms; such information is not possible to obtain in vivo. To analyze the influence of shape on aneurysm hemodynamics, nine aneurysm geometries are created and examined using CFD-ACE+. Characteristics of the aneurysm geometry are evaluated using quantitative indices previously developed by Ma et al [1]. Velocity fields calculated in all aneurysm geometries show multiple recirculation zones. The wall shear stresses acting at the fundi of the aneurysms are recorded over a complete cardiac cycle and compared. Some trends are suggested by this preliminary study.