【摘要】 目的探讨颅内顶端动脉瘤的血流动力学特点,分析动脉瘤生长、破裂的机制。方法选取5只兔颈动脉顶端动脉瘤模型,结合医学影像学资料,采用计算流体力学(CFD)有限元方法的软件,对兔颈动脉顶端动脉瘤的血流动力学行数值模拟,并对瘤颈、瘤壁等部位切应力大小随时间变化情况及分布进行分析。结果顶端动脉瘤在整个心动周期里切应力几乎都在迅速变化,变化时程与血流速度的变化时程一致,切应力主要存在于瘤颈,动脉瘤颈入口边界切应力0.21T达峰值,为0.83Pa;出口边界切应力0.32T达峰值,为0.38Pa;动脉瘤壁切应力接近于0。结论顶端动脉瘤瘤壁切应力是促进动脉瘤生长、扩大的可能原因之一。CFD数值模拟是一种反映动脉瘤血流动力学较好的方法。更多还原

【Abstract】 Objective To investigate the hemodynamic shear stress on carotid artery terminal aneurysms and the possible mechanism of growth and rupture of aneurysms. Methods Taking an experimental aneurysm in rabbits for example, hemodynamic numerical simulation were processed with the computational fluid dynamics (CFD). Results The wall shear stress was more prominent at the neck than the wall and other areas of aneurysm. Its direction changes all the time, and the timing of the changes is coincident with the velocity of blood flow. The peak of shear stress at 0.21 T reached to 0.83 Pa,and the shear stress on the aneurismal wall is nearly 0. Conclusion The wall shear stress is formed by the impact of blood flow and changed by the velocity of blood flow. Wall shear stress is an important risk factor to cause endothelial damages of the neck of aneurysm and enlargement of the aneurysm. CFD simulation can provide important informations about the pathophysiological mechanisms of intracranial aneurysms and may be helpful for management.更多还原