目的 基于高分辨率磁共振血管壁成像和计算流体动力学技术,探讨大脑中动脉(MCA)粥样硬化性狭窄处斑块陡度与血流动力学的关系.方法 收集80例缺血性脑卒中、短暂性脑缺血发作且单侧动脉粥样硬化性MCA狭窄的患者(50％～99％)进行进行常规磁共振扫描及大脑中动脉狭窄处血管壁扫描.获得斑块、血管壁、血管壁剪切力比(WSSR)、狭窄处血管壁剪切力(WSS)的数值.根据有无缺血性脑卒中将患者分为有症状组和无症状组.比较两组在斑块、血管壁和血流动力学方面的差异.计算斑块陡度与血流动力学之间的相关性.结果 80例患者中症状组31例,无症状组49例.症状组较无症状组狭窄处管腔面积(LA)较小(2.33±1.12 VS 2.94±1.06,P=0.024),斑块面积(PA)较大(4.36.±2.13 VS 2.87±1.38,P=0.001),重构指数较大(1.13±0.21 VS 0.92±0.19,P=0.001),WSSR(9.93,8.42 VS 5.75,3.68,P=0.009)和WSS(52.41±16.92 VS 38.37±17.26,P=0.018)较高,斑块陡度(1.24,1.17 VS 0.94,0.91,P=0.014)较大.与无症状组相比,症状组有更多的强化斑块(24 vs 13,P=0.03),正性重构(23 vs 20,P=0.001).斑块陡度与WSSR呈正相关(r=0.879,P＜0.001).结论 斑块陡度是MCA粥样硬化斑块的一个重要特征,在以往的研究中未引起足够的重视.大的斑块陡度更容易引起脑卒中.
Plaque Steepness Is Associated with Hemodynamics in Patients with Atherosclerotic Middle Cerebral Artery Stenosis
Objective To evaluate the relationship between plaque steepness and hemodynamics in middle cerebral artery(MCA)stenosis based on high-resolution magnetic resonance imaging and computational fluid dynamics.Methods Eighty consecutive patients with recent ischemic stroke,transient ischemic attack who accompanying with unilateral atherosclerotic MCA stenosis(50％-99％)were prospectively recruited.All patients underwent cross-sectional scan of the stenotic MCA vessel wall.The parameters and features of the plaque,vessel wall,translesional wall shear stress ratio(WSSR),wall shear stress in stenosis(WSS)were obtained.The patients were divided into symptomatic group and asymptomatic group.The differences in plaque,vessel wall,and hemodynamics were compared between two groups.Correlations between the plaque steepness and hemodynamics were calculated.Results Of the 80 patients,31 were divided to symptomatic group,the other 49 belonged to asymptomatic group.The symptomatic group had a smaller lumen area(2.33+1.12 VS 2.94±1.06,P=0.024),larger plaque area(4.36.±2.13 VS 2.87±1.38,P=0.001),larger remodeling index(1.13±0.21 VS 0.92±0.19,P=0.001),higher WSSR(9.93,8.42 VS 5.75,3.68,P=0.009)and WSS(52.41±16.92 VS 38.37±17.26,P=0.018),larger the radio of height/width(1.24,1.17 VS 0.94,0.91,P=0.014)at the most stenotic site.The symptomatic group had more enhanced plaques(24 vs 13,P=0.03),positive remodeling patients(23 vs 20,P＜0.001)than the asymptomatic group.The ratio of height/width(r=0.879,P＜0.001)showed positive correlation with WSSR,respectively.Conclusion Steepness is an important feature of atherosclerotic plaques,which doesn't get enough attention in past researches.Individuals with steep plaque might be more prone to stroke.
万方数据
维普
