大脑中动脉狭窄形态学与血流动力学的数值模拟相关性分析

Correlation analysis between morphology of middle cerebral artery stenosis and hemodynamics based on numerical simulation

目的探讨大脑中动脉狭窄形态学指标与血流动力学参数的内在联系。方法选取2019年7月至2022年3月牡丹江医学院附属红旗医院影像科诊断为大脑中动脉M1段(MCA-M1)狭窄的21例患者颅脑CT血管造影图像进行3D模型重建,模型光滑后测量形态学数据及划分网格计算血流动力学,结果可视化后进行采点及统计学分析。结果MCA-M1段狭窄区域壁面剪切力(WSS)明显升高,狭窄两端震荡剪切指数(OSI)升高;狭窄率、狭窄体积与OSI无明显直线相关,狭窄长度与OSI、WSS均无明显直线相关;不同狭窄率、狭窄体积WSS存在差异,狭窄率增高,WSS增大,呈正相关(r_(s)=0.788,P=0.000),狭窄体积减小,WSS增大,呈负相关(r_(s)=-0.769,P=0.000)。结论大脑中动脉狭窄时血流动力学发生改变,狭窄率、狭窄体积与WSS关系密切,可作为了解动脉粥样硬化血流动力学改变的重要窗口。

Objective To explore the internal relationship between morphological indexes of middle cerebral artery stenosis and hemodynamic parameters.Methods A total of 21 patients diagnosed with middle cerebral artery M1 segment(MCA-M1)stenosis in the Imaging Department of Hongqi Hospital Affiliated to Mudanjiang Medical University from July 2019 to March 2022 were selected.Three-dimensional model reconstruction was performed on the cerebral CT angiogram images.After model smoothing,the morphological data were measured and meshed for calculation of hemodynamic parameters.Sampling points and statistical analysis were performed after result visualization.Results Wall shear stress(WSS)of stenosis region in MCA-M1 increased obviously,and oscillatory shear index(OSI)of both ends of stenosis increased.There was no significant linear correlation between stenosis rate or stenosis volume and OSI,while there was no significant linear correlation between stenosis length and OSI or WSS.There were differences in WSS with different stenosis rates and stenosis volumes.WSS increased with the increase of stenosis rate,showing a positive correlation(r_(s)=0.788,P=0.000),and increased with the decrease of stenosis volume,showing a negative correlation(r_(s)=-0.769,P=0.000).Conclusion Hemodynamic parameters will change during the middle cerebral artery stenosis.The stenosis rate and stenosis volume are closely related to WSS,which can be used as an important window to understand hemodynamic changes in atherosclerosis patients.