Abstract: Objective　To investigate the correlation between unilateral middle cerebral artery (MCA) M1 segment occlusion and the unilateral advantages of anterior cerebral artery (ACA) indicated by magnetic resonance angiography (MRA) and posterior cerebral artery (PCA) indicated by 3-dimentional arterial spin labeling (3D ASL). Methods　From January 2018 to July 2021, 60 patients with unilateral MCA M1 segment occlusion indicated by MRA were collected, induding 34 males and 26 females, who were 33-78(51.2±7.6)years old. According to whether there was ACA or PCA unilateral advantages, they were divided into a unilateral advantage group and a control group. Through 3D ASL imaging sequence, the differences between the two groups in intra-arterial high signal display were compared. At the same time, the cerebral blood flow (CBF) of MCA supply area was measured, and the infarct area was calculated according to the DWI sequence. t and χ² tests were used. Results　Among the 60 patients, 87.9% (29/33) of the patients in the lateral dominant group and 48.1% (13/27) of the patients in the control group showed intra-arterial high signal, with a statistical difference (χ²=11.162, P<0.001). The CBF value of the middle cerebral artery blood supply area of the partial advantage group was (56.43±11.65) ml/100 g×min, which was higher than that of the control group [(42.58±14.52) ml/100 g×min], with a statistical difference (t=4.101, P<0.001). Meanwhile, the infarct area of the partial advantage group was smaller than that of the control group [(262.25±86.52) mm² vs. (768.54±168.65) mm²], with a statistical difference (t=-15.017, P<0.001). Conclusions　Both the advantage of cerebral artery lateralization and the high signal in the artery can indicate the establishment of collateral circulation after unilateral MCA M1 occlusion, but the high signal in the artery is more sensitive and accurate. The establishment of collateral circulation has positive significance for the selection of a treatment plan and for the patients' clinical prognosis.

Key words: Leptomeningeal anastomosis, Collateral pathway, Middle cerebral artery, Arterial spin labeling

摘要： 目的　探讨单侧大脑中动脉（MCA）M1段闭塞后，磁共振血管成像（MRA）提示同侧大脑前动脉（ACA）及大脑后动脉（PCA）偏侧优势与三维动脉自旋标记（3D ASL）成像提示动脉内高信号之间的相关性。方法　收集2018年1月至2021年7月经MRA提示单侧MCA M1段闭塞患者60例，男34例，女26例，年龄33～78（51.2±7.6）岁。依据有无ACA、PCA偏侧优势分为偏侧优势组和对照组，通过3D ASL成像序列，对比两组动脉内高信号显示差异。同时测量患侧MCA供血区脑血流量（CBF）值，并依据DWI序列统计梗死区面积。采用t检验、χ²检验。结果　60例患者中，偏侧优势组出现动脉内高信号为87.9%（29/33），对照组为48.1%（13/27），两组比较差异有统计学意义（χ²=11.162，P<0.001）。偏侧优势组MCA供血区CBF值为（56.43±11.65）ml/100 g×min，高于对照组的（42.58±14.52）ml/100 g×min，同时偏侧优势组梗死区面积小于对照组［（262.25±86.52）mm²比（768.54±168.65）mm²］，差异均有统计学意义（t=4.101、-15.017，均P<0.001）。结论　大脑动脉偏侧优势及动脉内高信号均可提示单侧MCA M1段闭塞后软脑膜侧支循环建立状态，但动脉内高信号更为敏感和准确，侧支循环的建立对于患者治疗方案的选择及临床预后均具有积极意义。

关键词: 软脑膜动脉, 侧支循环, 大脑中动脉, 动脉自旋标记