Structure of pulsatile flow in a model of elastic cerebral aneurysm

This study examines the effect of aneurysmal wall elasticity on the structure of flow within an elastic aneurysm during pulsatile flow. We visualized flow structure in a model of an elastic saccular aneurysm located at the bifurcation of the anterior cerebral artery and extending to the anterior communicating artery, and measured changes in the diameter of the aneurysm wall during pulsatile flow using particle imaging velocimetry (PIV). We similarly measured these features during steady flow by PIV and found that dilation of the aneurysmal wall absorbed the dynamic energy within the aneurysm. Accordingly, aneurysm wall elasticity functions as a biocompatible reaction that relieves wall shear stress acting on the vascular wall during pulsatile flow, and should thus inhibit the development and rupture of an aneurysm.