Suppression of Wall Shear Stress inside Intracranial Aneurysms by Simple Stents

Abstract

The effect of a simple bare-metal stent on suppression of wall shear stress inside a spherical intracranial aneurysm model was experimentally examined by two dimensional particle image velocimetry in vitro. The flow model simulated an intracranial aneurysm induced both at the side wall and at the apex of bifurcation in the cerebral arteries. In order to assess the simple bare metal stent characteristics, the variation of wall shear stress was examined using both stented and non-stented models. The flow behavior inside the stented aneurysm was not smooth and wall shear stress was significantly smaller inside the aneurysm. For both models, the maximum and the temporal and spatial averaged wall shear stress in the stented model is reduced by at least 50 % smaller than those in the non-stented models. Stent deployment effectively suppresses the temporal and spatial variations, and the magnitude of wall shear stress. Consequently, even simple stent might be an effective treatment to retard the progress of cerebral aneurysms.