大脑中动脉粥样硬化斑块的特征及意义

Characteristics and significance of atherosclerotic plaque in the middle cerebral artery

目的 通过高分辨磁共振成像(HR-MRI)技术评估大脑中动脉(MCA)粥样硬化患者的斑块特征与发生缺血性症状的关系。方法 回顾性分析97例HR-MRI检查的MCA粥样硬化M1段狭窄患者的临床资料,根据动脉斑块是否导致缺血性症状的情况分为症状组和无症状组,比较两组的动脉粥样硬化危险因素、管腔狭窄程度、斑块特征。结果 97例患者中症状组62例,无症状组35例。症状组患者管腔重度狭窄比例(66.1%)高于无症状组(34.3%),差异有统计学意义(P<0.05)。两组斑块主要分布于腹壁、上壁(75.3%)及M1段近端(80.4%)。症状组斑块上壁分布比例(43.5%)高于无症状组(22.9%),差异有统计学意义(P<0.05)。症状组斑块明显强化比例(61.2%)、斑块负荷(81.2±11.1)均高于无症状组(25.7%,57.2±8.1),差异有统计学意义(P均<0.01)。结论 MCA粥样硬化患者斑块多分布于腹壁、上壁、M1段近端;强化程度、斑块负荷与是否发生缺血性症状具有相关性。

Objective To evaluate the relationship between plaque characteristics and ischemic symptoms in patients with middle cerebral artery(MCA) atherosclerosis by high-resolution magnetic resonance imaging(HR-MRI).Methods The clinical data of 97 patients with atherosclerotic stenosis in MCA M1 segment examined by HR-MRI were analyzed retrospectively.Patients were divided into symptomatic and asymptomatic groups according to whether the arterial plaque caused ischemic symptoms.The risk factors for atherosclerosis,the degree of lumen stenosis,and the characteristics of plaque were compared between the two groups.Results Among the 97 patients,there were 62 patients in the symptomatic group and35 patients in the asymptomatic group.The proportion of patients with severe lumen stenosis in the symptomatic group was significantly higher than that in the asymptomatic group(66.1% vs 34.3%,P<0.05).Plaques were mainly distributed in the ventral wall,superior wall(75.3%),and proximal M1 segment(80.4%) in the two groups.The proportion of plaques distributed in the superior wall in the symptom group was significantly higher than that in the asymptomatic group(43.5% vs22.9%,P<0.05).The plaque enhancement ratio and plaque burden in the symptomatic group were significantly higher than those in the asymptomatic group(61.2%/81.2±11.1 vs 25.7%/57.2±8.1,both P<0.01).Conclusions Plaques in patients with MCA atherosclerosis are mostly distributed in the ventral wall,superior wall,and proximal M1 segment.The degree of enhancement and plaque burden are related to the occurrence of ischemic symptoms.