3.0T MR高分辨增强扫描对缺血性脑卒中颅内动脉粥样硬化斑块的诊断价值

Diagnostic value of 3.0T MR high resolution enhanced scan in intracranial atherosclerotic plaque in patients with ischemic stroke

目的使用高分辨MR成像确定颅内梗塞区域血管是否存在增强的动脉粥样硬化斑块,同时分析斑块强化程度随时间的变化趋势。方法回顾性分析2016年8月?2017年9月入住我院神经内科的缺血性卒中患者32例的临床资料及梗塞区域斑块的位置及强化特征;以垂体增强度为参考标准,来判断斑块的强化程度,分3组:明显强化、轻度强化和无强化,根据头颅MR平扫(DWI高信号)至高分辨MR检查时间间隔分为早期组(小于4周)、中期组(4?12周)和晚期组(大于12周),分析斑块强化随时间变化趋势。根据SPSS 20.0统计软件进行数据处理,采用Kruskal-Wallis H检验分析3组间斑块的强化度随时间变化关系,采用Spearman相关系数量化关联强度。结果 32例患者中,27例呈偏心性斑块,5例呈向心性强化;19例位于大脑中动脉M1段,11例位于基底动脉,2例位于椎动脉颅内段;早期组15例、中期组11例和晚期组6例;早期组患者中,明显强化12例,轻度强化2例,无强化1例,中期组明显、轻度及无强化分别为5、4、2例,晚期组分别为1、2、3例;3组间强化程度差异具有统计学意义(P<0.05),随时间不断增加,强化程度有减弱趋势。结论在缺血后4周内脑卒中区域斑块多数呈明显强化;相对于早期卒中强化表现,中期及晚期斑块强化减弱或消失。颅内动脉粥样硬化斑块强化与急性缺血性脑卒中的发生有密切联系,颅内斑块强化可能是斑块炎症的标志物。

Objective To determine whether the blood vessels in the intracranial infarction area enhance atherosclerotic plaques using high resolution MR imaging and to analyze the degree of plaque enhancement with time. Methods The clinical data of 32 patients with ischemic stroke in our hospital from Aug 2016 to Sep 2017 were analyzed retrospectively. The location, morphology and enhancement of plaque in infarcted area were analyzed. According to the first MR level scan（DWI high signal） to high resolution MR examination the time interval was divided into early group（less than 4 weeks）,middle group（4？12 weeks） and later group（more than 12 weeks）,the trend of plaque enhancement with time was analyzed. Data were processed according to SPSS 20.0 statistical software. Kruskal-Wallis H test was used to analyze the relationship between the intensities of patches in the three groups with time. Spearman correlation coefficient was used to quantify the correlation intensity. Results Of the 32 patients,27 patients had eccentric plaques and 5 patients had concentric enhancement. 19 cases were located in the middle cerebral artery M1 segment,11 cases were in the basilar artery and 2 cases were in the intracranial segment of the vertebral artery.15 cases were in early group,11 cases in middle group and 6 cases in later group. Early group of patients, significantly enhanced were 12 cases, mild enhancement were 2 cases,no enhancement was 1 case.The intensity of the three groups was statistically significant（P〈0.05）. Conclusion In patients treated 4 weeks after ischemia, most of the stroke plaques were significantly enhanced. Compared with early stroke enhancement, the middle and late stage the plaque intensification weakened or disappeared. The results show that intracranial atherosclerotic plaque enhancement and acute ischemic stroke are closely linked, intracranial plaque enhancement may be a marker of plaque inflammation.