高分辨率MR管壁成像评估缺血性脑卒中患者血管斑块稳定性

High-resolution MR wall imaging for evaluation on stability of vascular plaque in ischemic stroke patients

目的分析高分辨率MR管壁成像(HR-VWI)评估不同亚型缺血性脑卒中患者血管斑块稳定性的价值。方法回顾性分析43例临床诊断缺血性脑卒中患者的MR HR-VWI资料,包括15例载体动脉(斑块或血栓)阻塞穿支(PAOPA)(PAOPA组),22例动脉到动脉栓塞(ATAE)(ATAE组),3例低灌注/栓子清除下降(HP/IEC)及3例混合机制(MM)。比较PAOPA组与ATAE组责任斑块形态、分布、位置及管腔表现的差异。结果PAOPA组与ATAE组间责任斑块分布差异无统计学意义(χ^(2)=12.16,P>0.05)。ATAE组责任斑块表面不规则发生率(63.64%)及斑块负荷[(70.39±11.27)%]均高于PAOPA组[26.67%,(63.11±10.57)%,χ^(2)=8.87,t=4.02,P=0.04、0.03]。ATAE组斑块2级强化发生率(81.82%)高于PAOPA组(26.67%,χ^(2)=7.51,P=0.03),斑块0级强化发生率(9.09%)低于PAOPA组(46.67%,χ^(2)=8.02,P=0.03);2组斑块偏心性分布发生率、斑块内T1高信号发生率、斑块厚度、责任斑块处管腔狭窄率及血管重构方式差异均无统计学意义(P均>0.05)。结论HR-VWI对鉴别不同亚型缺血性脑卒中血管斑块的稳定性具有一定价值;相比PAOPA,ATAE斑块HR-VWI更多表现出不稳定特征。

Objective To analyze the value of high resolution MR vessel wall imaging(HR-VWI)for evaluation on the stability of vascular plaques in different subtypes of ischemic stroke.Methods Data of 43 patients with clinically diagnosed ischemic stroke were retrospectively analyzed.Among 43 patients,15 patients were found with parent artery(plaque or thrombus)occluding penetrating artery(PAOPA)(PAOPA group),22 with artery-to-artery embolism(ATAE)(ATAE group),3 with hypoperfusion/impaired emboli clearance(HP/IEC)and 3 with multiple mechanism(MM).The morphology,distribution,location and luminal manifestations of responsible plaques were observed and compared between PAOPA group and ATAE group.Results There was no significant difference of the distribution of responsible plaques between PAOPA group and ATAE group(χ^(2)=12.16,P>0.05).The incidence of plaque surface irregularity(63.64%)and plaque load of responsible plaques([70.39±11.27]%)in ATAE group were higher than those in PAOPA group(26.67%,[63.11±10.57]%,χ^(2)=8.87,t=4.02,P=0.04,0.03).The incidence of plaque grade 2 enhancement in ATAE group(81.82%)was higher than that in PAOPA group(26.67%,χ^(2)=7.51,P=0.03),and the incidence of plaque grade 0 enhancement in PAOPA group(9.09%)was lower than that in PAOPA group(46.67%,χ^(2)=8.02,P=0.03).There was no significant difference of the incidence of eccentric distribution of plaque,the incidence of T1 high signal in the plaque,the plaque thickness,the degree of lumen stenosis at the location of the responsible plaque nor the vascular remodeling methods between the 2 groups(all P>0.05).Conclusion HR-VWI had certain value in evaluating vascular plaque stability of different subtypes of ischemic stroke.Compared with PAOPA,ATAE plaques showed more unstable characteristics on HR-VWI.