三维伪连续动脉自旋标记评价症状性大脑中动脉慢性闭塞后脑灌注状态的临床价值

目的探讨三维伪连续动脉自旋标记(3D-pCASL)在症状性大脑中动脉(MCA)慢性闭塞后脑灌注状态的评价价值。方法前瞻性选择收集我院2017年8月至2020年3月具有临床症状而就诊的MCA慢性闭塞患者42例,进行常规MRI、MRA及3D-pCASL检查,3D-pCASL采用两个标记延迟时间(PLD=1.5 s、2.5 s)。分别测量患侧、镜像侧MCA感兴趣区(ROI)脑白质血流量(CBF),并计算患侧与镜像侧比值,比较分析患侧与镜像侧双时相脑灌注CBF值的差异。结果 42例单侧MCA慢性狭窄患者,脑内DWI均未见扩散受限信号灶。患侧和镜像侧PLD=1.5 s时CBF为(32.94±9.99)/(41.72±8.46)],均较PLD 2.5 s(40.29±8.97)/(45.69±9.09)]降低,且患侧PLD较镜像侧降低更明显,差异有统计学意义(P0.05)。患侧CBF较镜像侧呈低灌注状态31例(73.81%),其中严重缺血后失代偿5例(11.90%),CBF正常灌注7例(16.67%),CBF高灌注4例(9.52%),患侧侧支循环完全代偿。结论全脑3D-pCASL评估症状性大脑中动脉慢性闭塞患者脑白质CBF可信度高,可作为常规序列,为临床诊疗提供量化依据。

Clinical value of three-dimensional pseudocontinuous artery spins labeling in evaluating cerebral perfusion after symptomatic chronic middle cerebral artery occlusion

Objective To investigate the value of three-dimensional pseudocontinuous artery spin labeling (3D-pCASL)in evaluating cerebral perfusion after symptomatic chronic middle cerebral artery(MCA) occlusion.Methods A total of 42 patients with chronic MCA occlusion who presented with clinical symptoms in our hospital from August 2017 to March 2020 were prospectively selected for conventional MRI,MRA and 3D-pCASL examinations.The delay time after the use of two markers for 3D-pCASL (PLD=1.5 s and 2.5 s) was analyzed.The cerebral white matter blood flow(CBF)in the region of interest (ROI) of the affected side and the mirrored side of the MCA was measured respectively,and the ratio of the affected side to the mirrored side was calculated.The CBF values of the bi-temporal cerebral perfusion on the affected side and the mirrored side were compared and analyzed.Results In 42 patients with unilateral MCA chronic stenosis,no diffusion-limited signal foci were found on DWI in the brain.The CBF values of the affected side and mirrored side with PLD of 1.5 s(32.94±9.99)/(41.72±8.46) was lower than that of PLD of 2.5 s (40.29±8.97)/(45.69±9.09),and the PLD on the affected side decreased more significantly than that of mirrored side(P<0.05).There were 31 cases (73.81%) with hypoperfusion on the affected side of CBF compared with the mirrored side,including 5 cases(11.90%) with severe ischemic decompensation,7 cases(16.67%) with normal CBF perfusion,and 4 cases(9.52%) with high CBF perfusion,with complete compensation of the collateral circulation on the affected side.Conclusion The whole-brain 3D-pCASL has high reliability in evaluating CBF of white matter in patients with symptomatic chronic MCA occlusion,and can be used as a conventional sequence to provide a quantitative basis for clinical diagnosis and treatment.