Nowadays approximately 3–6% of the population is estimated to have unruptured cerebral aneurysms. The rupture risk of aneurysms can be predicted by using computational tools and patient-specific models. As an ideal method, we can assess the risk factors by determining the blood tension and the material strength of the wall tissue in the aneurisms. Although it is hard to obtain aneurismal material strength without invasive measurement, it is possible to estimate the wall tension by numerical simulation [1].Copyright © 2009 by ASME