目的 调查急性缺血性卒中(AIS) 头颅核磁DWI-FLAIR不匹配与侧枝循环的 相关性。方法 前瞻性收集AIS患者，发 病24小时内完成多序列头颅MR检查，部分 患者亦接受DSA检查。若DWI阳性而FLAIR 阴性，判为“DWI-FLAIR”不匹配；若二 者均阳性，则判为“DWI-FLAIR”匹配。 FLAIR像上大血管远端脑表面点状、管状 或曲线样血管高信号影判读为“远端血 管高信号征(FHV)阳性”。美国介入和治 疗神经放射学学会DSA评估系统对缺血区 灌注进行分级，0-2级为灌注不良，3-4级 为灌注良好。结果 共43例患者入组。其 中17例亦接受了DSA检查。FHV预测大动脉 闭塞或重度狭窄敏感性62%(95% 可信区间 41%-79%)，特异性88%(62%-98%)，阳性预 测值89%(64%-98%)，阴性预测值60%(39%- 78%)。在DWI-FLAIR不匹配与匹配组间除 了发病至行MR时间外，其他临床特征无显 著区别。DSA显示两组间侧枝循环灌注级 别无显著差异(卡方确切检验p=0.644， n=17)。结论 FHV可预测近端大动脉闭塞 或狭窄。DWI-FLAIR不匹配不足以预测侧 枝循环的代偿程度

Objective To investigate the correlation between the DWI-FLAIR mismatch and collateral circulation. Methods AIS patients were recruited prospectively to undergo multimodal MR within 24 hours after onset.Some cases also underwent angiography. DWI-FLAIR mismatch is defined as DWI-positive and FLAIR-negative, DWI-FLAIR match as both positive.FLAIR hyperintense vessles signs (FHV) is described as focal, tubular, or serpentine hyperintensities in the distal of large arteries in the subarachnoid space.Collateral perfusion was graded by the American Society of Interventional and Therapeutic Neuroradiology criteria, 0~2 was graded as poor,3~4 was graded as good. Results 43 patients were included.17 patients also underwent angiography.DWI was 100% positive,FLAIR was 30.2% positive. FHV identified patients with proximal large artery occlusion or severe stenosis with 62%(95% CI 41%~79%)sensitivity，88%(62%~98%) specificity,89%(64%~98%)positive predictive value，60%(39%~78%)negative predictive value.There was no significant difference of FHV presence (p=0.925) and collateral perfusion grade (Fisher's exact test p=0.644) between the two groups. Conclusions FHV can help to identify proximal large artery occlusion or severe stenosis in AIS.DWI-FLAIR mismatch is insufficient to predict collateral circulation