血流转向装置对动脉瘤血流动力学影响的数值模拟研究

目的 探讨低孔率血流转向装置对脑动脉瘤内血流动力学的影响及其临床应用的可行性.方法 应用绘图软件虚拟建立宽颈和窄颈的弯曲管侧壁型动脉瘤三维模型.采用脉动流对不同动脉瘤模型进行数值模拟研究,并虚拟植入血流转向装置于载瘤动脉内并覆盖瘤颈.应用Fluent软件计算,比较低孔率血流转向装置植入前后载瘤动脉及动脉瘤内瘤动力学变化.结果 血流转向装置植入后窄颈与宽颈动脉瘤内的血流动力学均发生显著变化.窄颈动脉瘤瘤颈远侧壁的速度峰值与壁面剪应力在血流转向装置植入后均有显著;宽颈动脉瘤中表现出同样的趋势,但下降幅度低于窄颈动脉瘤.结论 数值模拟研究证实低孔率血流转向装置显著改变动脉瘤内的血流动力学,对防止动脉瘤出血或再出血非常重要.

Effects of flow diverter with low porosity on cerebral aneurysms:a numerical simulative study

objective To examine the influence of flow diverter on the alterations of cerebral intraaneurysmal hemodynamics.Methods One wide-necked and one narrow-necked sidewall aneurysm in curved vessels were virtually reconstructed.Pulsatile computational fluid simulations were performed on each model for hemodynamic analysis.And the flow diverters were virtually deployed tO cover the aneurismal neck with parent vessels.The hemodynamic changes in parent vessels and aneurysms after a deployment of flow diverter devices with low porosity were studied by the Fluent software.Results After a deployment of flow diverter,the hemodynamics in aneurysm sac changed significantly.The peak velocity and wall stress strength in impingement zone of narrow-necked aneurysms decreased after the placement of a flow diverter.And similar change also occurred in wide-necked aneurysms,but with a less decreased span.Conclusion Numerical simulation confirms that a flow diverter with low porosity significantly may modify the hemodynamics in aneurysms.Which is important for prevention of blieding or rebleeding of intracranial aneurysm.