FLAIR和SWI序列评估缺血性脑卒中二级侧支循环

Assessment on the second-level collateral circulation inischemic stroke using FLAIR and SWI sequences

目的:探讨液体衰减反转恢复(FLAIR)序列上显著高信号血管(HSV)征与磁敏感加权成像(SWI)上明显不对称多发低信号血管(MLSV)征的相关性及两者对缺血性脑卒中的诊断及预后评估价值。方法:回顾性分析2016年7月-2017年12月经MRA或CTA证实为大脑中动脉M1段完全闭塞的72例缺血性脑卒中患者的临床和MRI资料。以美国国立卫生研究院卒中量表(NIH Stroke Scale,NIHSS)来评估患者脑梗死临床表现的严重程度,并根据出院NIHSS评分将患者分为预后较好(<13分)和预后差(13~38分)两组。对FLAIR图像上HSV征和SWI上MLSV征的严重程度评分(取值范围分别为0~8分和0~12分)进行Spearman相关性分析。采用卡方检验比较两个预后组之间性别、疾病史、HSV征分级(高:HSV评分≥7、中等:HSV评分5~6、低:HSV评分≤4)和MLSV分级(高:MLSV评分>4;低:MLSV评分≤4)的差异,采用非参数检验比较年龄、入院NIHSS评分和入院DWI上梗死灶体积评分(取值范围为0~10分)的差异。比较高、低MLSV分级组及高、低HSV分级组(分别为评分>4和≤4)之间性别、疾病史、年龄、入院NIHSS评分和入院DWI上梗死灶体积评分(取值范围为0~10分)的差异。采用Logistic回归分析对出院NIHSS评分与入院NIHSS评分、DWI梗死灶体积评分、HSV和MLSV分级之间的相关性进行评估。结果:72例中,FLAIR序列上HSV严重程度评分与SWI序列上MLSV严重程度评分之间呈中度正相关(r=0.452,P=0.010)。Logistic回归分析结果显示,入院NIHSS评分越高则出院NIHSS评分越高(OR=1.493,P=0.001),相应预后越差;HSV严重程度分级越高(OR=0.513,P=0.010)或MLSV严重程度分级越高(OR=0.199,P=0.041),出院NIHSS评分越低,提示相应预后越好。明显不对称MLSV征与入院时NIHSS评分及入院DWI上梗死灶体积评分之间均无显著相关性(P>0.05)。HSV分级高的患者有较低的入院NIHSS评分(P=0.022)和较低的入院DWI上梗死灶体积评分(P=0.042)。结论:对FLAIR序列上高信号血管征和SWI序列上不对称多发低信号血管征的严重程度进行评分,有助于缺血性脑卒中患者的预后评估,并可为临床治疗提供有价值的信息。

Objective:To investigate the correlation between the substantial high signal vessel(HSV)sign on fluid-attenuated inversion recovery(FLAIR)and prominent asymmetric multiple low signal vessel(MLSV)sign on susceptibility-weighted imaging(SWI)and their value in providing independent diagnostic and prognostic information in patients with ischemic stroke.Methods:The clinical and MRI data of 72 patients with ischemic stroke due to occlusion of M1 segment of the middle cerebral artery(MCA)confirmed by MRA or CTA from July 2016 to December 2017 were analyzed retrospectively.The clinical severity of stroke were assessed using National Institute of Health Stroke Scale(NIHSS),and then the patients were divided into two groups according to the NIHSS score at admission time(NIHSS AT):good prognosis group(NIHSS AT<13)and poor prognosis group(13≤NIHSS AT≤38).The correlation of the severity score(ranged from 0 to 8)of HSV sign on T 2-FLAIR and that(ranged from 0 to 12)of MLSV sign on SWI was evaluated using Spearman correlation analysis.Theχ2-test was used to compare the differences of the gender,diseases history,HSV sign severity grades(high:HSV score≥7;medium:HSV score 5~6;low:HSV scroe≤4)and MLSV sign severity grades(high:MLSV score>4;low:MLSV score≤4)between the two prognosis groups.The diffe-rences of age,admission NIHSS score and admission lesion volume score(AVS,ranged from 0 to 10)on DWI were analyzed using the Mann-Whitney U test.Subsequently,the differences of the gender,diseases history,age,admission NIHSS score and AVS were further compared between the MLSV high-and low-grade groups,and the HSV high-and low-grade groups(HSV score>4 and≤4),respectively.The Logistic regression analysis was used to evaluate the correlation between discharge NIHSS score and admission NIHSS score,admission lesion volume score,HSV grade and MLSV grade,respectively.Results:Among the 72 patients,there was a moderate correlation between HSV severity score on FLAIR and MLSV severity score on SWI(r=0.452,P=0.010).The Logistic regression analysis showed that the higher the admission NIHSS score,the higher the discharge NIHSS score(OR=1.493,P=0.001)which meant the worse the corresponding prognosis.The higher the HSV severity score(OR=0.513,P=0.010)or the higher MLSV severity score(OR=0.199,P=0.041),the lower discharge NIHSS score which meant the better the corresponding prognosis.The grade of asymmetric MLSV sign on SWI had no correlation with the admission NIHSS score and the admission lesion volume score on DWI(P>0.05).The patients with higher HSV severity grade had lower admission NIHSS score(P=0.022)and higher lesion volume score on DWI(P=0.042).Conclusion:The HSV sign severity score on FLAIR and MLSV sign severity score on SWI are helpful to evaluate the prognosis of patients with ischemic stroke,and can provide valuable information to guide clinical treatment.