Two-Dimensional Optimization of a Stent for an Aneurysm

Abstract

This work attempts to optimize stents that are implanted at the neck of coronary or cerebral aneurysms to effect a flow diversion. A two-dimensional version of the stent, which is a series of struts and gaps placed at the neck, is considered as the first step. Optimization is carried out based on the principles of exploration of design space using reductions in velocity and vorticity in the aneurysm dome as the objective functions. Latin hypercube sampling first develops 30–60 samples of a strut-gap arrangement. Flow past an aneurysm with each of these samples is computed using the commercial software FLUENT and the objective functions evaluated. This is followed by a Kriging procedure that identifies the nondominated solutions to the system, which are the optimized candidates. Three different cases of stents with rectangular or circular struts are considered. It is found that placing struts in the proximal region of the neck gives the best flow diversion.