Visualization of Flow Changes in Side Wall Aneurysm Models Subsequent to Stenting Using Laser Induced Fluorescence

Use of non-invasive diagnostic techniques (e.g. CT, MRI) reveal a large number of asymptomatic cerebral aneurysms. Current studies suggest that unruptured asymptomatic aneurysms are in various stages of development and most may progress to rupture. The morphology of the aneurysm and pulsatile flow conditions are determinant factors in aneurysm growth which may lead to rupture with high mortality and morbidity. This study investigates the changes of flow patterns in an experimental 2-D side wall aneurysm model before and after placement of a stent in the parent vessel transversing the ostium of the aneurysm. Implantation of a stent, which covers the aneurysmal ostium, alters local hemodynamics. By reducing the flow into the aneurysm a thrombo-occlusion of the aneurysmal pouch can be achieved. Preliminary studies (Wakhloo et al, 1994) have shown that stents were able to permanently occlude experimental side wall aneurysms of the canine carotid artery. Furthermore, stents induce endothelialization of the stented vessel lumen. However, stent mechanical properties, geometry, and local hemodyamics determine the long term biocompatibility and patency of the implant. (Wakhloo et al, 1995).