Although endosaccular coiling of aneurysms has been shown to be effective and has arguably replaced surgery for the treatment of most aneurysms it has significant limitations in achieving durable occlusion of many large and giant aneurysms because of a propensity for recanalization. For this reason flow diverting stents are increasingly been considered as a therapeutic alternative to surgical clipping and endovascular coiling. The aim of flow diverting stents is to create a stable hemodynamic environment within the aneurysm favorable for thrombosis and aneurysm occlusion, while maintaining the patency of any side branch that may be crossed by the device. The hemodynamic performance of these devices and the outcome of the procedures depend on their porosity and geometric characteristics [1]. However, the local porosity and stent cell geometry after implantation into a given artery depends on the choice of the stent diameter. Typically, stents are oversized to achieve a good wall apposition. Thus, the goal of this study was to investigate the effect of stent oversizing on its hemodynamic performance.