基于多孔阶跃面技术的颅内动脉瘤数值模拟方法研究

Study on numerical simulation method of intracranial aneurysms based on porous jump

目的 研究基于多孔阶跃面技术模拟构建的血流导向装置(FD)在颅内动脉瘤数值模拟方面的可行性及可靠性,为临床治疗颅内动脉瘤在支架选择方面提供理论支持。方法 纳入兰州大学第二医院神经外科一例颅内动脉瘤患者动脉瘤体数字减影血管造影(DSA)造影图像数据,通过Mimics等软件构建其基本几何模型并进行FD模型的置入,再进一步对所建模型进行网格划分和求解计算,以获得该模型血流动力学指标分布情况。结果 观测血流动力学指标,与置入前比较,发现模拟置入FD后动脉瘤体整体压力显著下降;瘤体平均壁面剪切力(WSS)整体下降,且动脉瘤体高WSS区域明显减少;另外FD置入对动脉瘤内部的涡量产生有较大影响,极大地降低了动脉瘤瘤体内部的血液流动速度。结论 对比既往大量研究数据,发现通过多孔阶跃面技术进行数值模拟所得结果与其保持一致,提示本研究方法行之有效,且较之其他方法更加快速、准确,在临床诊疗活动中有较大的应用前景。

Objective To study the feasibility and reliability of the flow diverter(FD)constructed based on the simulation of porous jump technology in the numerical simulation of intracranial aneurysm,and to provide theoretical support for stent selection in the clinical treatment of intracranial aneurysms.Methods A digital subtraction angiography(DSA)image of an intracranial aneurysm patient in the Department of Neurosurgery of the Second Hospital of Lanzhou University was included,and the basic geometric model was constructed by Mimics and other software and the FD model was inserted,and the model was further meshed and solved to obtain the distribution of the hemodynamic indexes.Results The hemodynamic indexes were observed and compared with the situation before placement,and it was found that the overall pressure of the aneurysm decreased significantly after the simulated placement of the flow-guiding device;the mean wall shear stress(WSS)of the aneurysm decreased overall,and the high WSS area of the aneurysm decreased significantly;in addition,the FD placement had a significant effect on the generation of vortex volume inside the aneurysm,which greatly reduced the blood flow velocity inside the aneurysm.Conclusion Comparing the data from a large number of previous studies,the results of the numerical simulation of intracranial aneurysm based on the porous jump are consistent with a large number of studies,indicating that the method is valid and feasible,and is faster and more accurate compared with other modeling methods,making it more promising to be applied to clinical treatment activities.