Particle Image Velocimetry (PIV) Flow Measurements of Carotid Artery Bifurcation with Application to a Novel Covered Carotid Stent Design

Abstract

Stenosed carotid artery is responsible for 60% of strokes in the United States and is the third major cause of death. Recently, there is an increasing interest in carotid artery stenting for treatment of cervical carotid artery bifurcation atherosclerotic disease. The ultimate goal of this study is to develop, prototype, test, and optimize a novel design of a covered carotid stent, in order to achieve emboli prevention and at the same time maintain the external carotid artery (ECA) branch flow. For this purpose, in the first stage, true-to-scale silicon replicas of anatomically realistic geometries of carotid arteries are fabricated and the flow field in the carotid bifurcation region is measured, utilizing particle image velocimetry (PIV) technique. These data are also used to validate the concurrent computational simulation results and fluid-structure interaction (FSI) analyses of the designed covered stents in the carotid artery models. Then, in the next stage, the stent prototypes will be deployed in the silicon models, and PIV flow measurements will be conducted to investigate the influence of each stent design on the flow behavior and the flow division between the internal and external carotid artery branches. Moreover, the capability of each covered stent design model in confining the atherosclerotic plaque fragments (emboli) will be evaluated experimentally. The preliminary stage of this study has demonstrated that the PIV and FSI computational simulations can complement each other to investigate the carotid flow towards our goal of determining the superior covered stent design that can bring about better emboli prevention and maintain the ECA branch vessel flow.