Understanding and Characterization of Hemodynamics in Non-Stented and Stented Cerebral Aneurysms

在美国，每年有28000人因颅内动脉瘤破裂而中风。其中近一半的人会死亡，更多的人会有严重的神经缺陷，需要长期的护理机构护理。在横跨动脉瘤孔的大脑动脉中放置支架有可能改变血流动力学，从而在动脉瘤囊内诱导自身血栓形成，阻止其进一步生长并防止其破裂。因此，支架植入术可能提供一种新的微创治疗模式。这个项目的目标是获得一个定量的理解和表征的血液动力学环境的改变在囊状脑动脉瘤内引起的放置腔内支架，一个微型网状管植入动脉。在一些临床病例中，单独支架植入导致动脉瘤愈合，但在其他病例中，支架植入会产生不良反应，导致动脉瘤破裂。该研究将量化支架的关键参数，如孔隙度、网格设计、支撑厚度和血管几何形状如何影响流动条件。计算流体动力学（CFD）和立体粒子图像测速（SPIV）将用于评估关键的通用动脉瘤几何形状和支架几何形状替代品，以及选择现实的患者特定动脉瘤几何形状。结果将确定开发有效和新型颅内支架所需的理想特性。

0302389MengAnnually, 28,000 people in the United States suffer strokes from ruptured intracranial aneurysms. Nearly half of these people will die and many more will have severe neurological deficits requiring long term nursing facility care. The placement of a stent in a cerebral artery across the orifice of an aneurysm has the potential to alter the hemodynamics in such a way as to induce self-thrombosis within the aneurysm sac, stopping its further growth and preventing its rupture. Thus stenting might offer a new, minimally invasive treatment paradigm. The goal of this project is to obtain a quantitative understanding and characterization of the alterations of the hemodynamic environment within a saccular cerebral aneurysm caused by the placement of an endoluminal stent, a miniature mesh tube implanted in an artery. In some clinical cases, stenting alone has led to the healing of the aneurysms, but in other cases stenting has generated adverse effects resulting in the rupture of the aneurysms. The research will quantify how key parameters of a stent such as porosity, mesh design, and strut thickness and vessel geometry affect the flow conditions. Computational Fluid Dynamics (CFD) and Stereoscopic Particle Image Velocimetry (SPIV) will be used to evaluate key generic aneurysm geometries and stent geometry alternatives and selected realistic patient specific aneurysm geometries. Results will identify the desirable properties necessary for the development of effective and novel intracranial stents.