MR T1加权像大脑中动脉高信号血管征在急性及亚急性脑梗死中的意义

目的 探讨急性及亚急性脑梗死患者MR T₁WI大脑中动脉高信号血管征(HVS)的临床意义。方法 回顾性分析2013年1月—2015年3月安徽医科大学第一附属医院收治的92例急性及亚急性大脑中动脉供血区脑梗死患者(脑梗死组)的临床及影像学资料,其中男54例、女38例,年龄41～94岁、平均(66.0±13.9)岁;收集同期非脑梗死脑部疾病患者及健康成人34例影像资料为对照组。所有研究对象行MRI平扫,其中脑梗死患者有68例行头颅3D时间飞跃法MRA(3D-TOF MRA)和/或CTA检查。观察所有研究对象MRI T₁WI大脑中动脉HVS,对比HVS阳性组与HVS阴性组患者脑梗死范围、血管病变程度、DWI-Alberta中风早期CT评分(DWI-ASPETS)以及临床表现。结果 对照组34例研究对象T₁WI均未出现HVS。92例脑梗死患者中有43例存在HVS(HVS阳性组),49例无HVS(HVS阴性组);两组间年龄、性别构成及合并基础疾病等一般临床情况比较,差异均无统计学意义(P值均>0.05);但入院时,HVS阳性组患者肌力低于HVS阴性组,差异有统计学意义(Z=1.978,P=0.048)。HVS阳性组平均梗死范围为(4.0±1.1)个脑叶、DWI-ASPETS中评分≤6分者占83.7% (36/43),HVS阴性组平均梗死范围为(2.5±0.9)个脑叶、DWI-ASPETS中评分≤6分占26.5% (13/49),两组比较差异均有统计学意义(P值均<0.01)。68例行MRA和/或CTA检查中,HMCA阳性组35例,其中动脉闭塞占71.4%(25/35),动脉狭窄占28.6%(10/35);HMCA阴性组33例,其中动脉闭塞占45.5%(15/33),动脉狭窄占39.4%(13/33),未见异常占15.1%(5/33);两组间差异有统计学意义(χ²=5.724,P＜0.05)。结论 急性及亚急性脑梗死患者MR T₁WI大脑中动脉HVS征提示动脉闭塞或严重狭窄,该征象可作为患者预后差的指标之一;认识HVS的意义,有助于理解梗死的发病原因,指导临床治疗以及判断预后。

The significance of the hyperintense middle cerebral artery sign on MR T1WI in acute and subacute cerebral infarction

Objective To explore the clinical significance of the hyperintense vessel sign(HVS) of middle cerebral artery on T₁-weighted images in acute and subacute cerebral infarction.Methods In this retrospective study, 92 patients [54 males, 38 females, aged 41-94 years, mean age (66.0±13.9) years] with acute and subacute cerebral infarction in middle cerebral artery territory in the First Affiliated Hospital of Anhui Medical University were enrolled from January 2013 to March 2015. Thirty-four subjects included the patients with other brain disease and normal subjects were enrolled to observe whether HVS appeared in normal brains or other diseases in the same period. All of them were undergone conventional MRI, 68 patients with cerebral infarction were undergone 3D-TOF MRA and/or CTA. HVS sign was observed on T₁WI. The extent of cerebral infarction, the degree of vascular lesion, DWI-Alberta stroke program early computed tomographic score (DWI-ASPETS scores) and the clinical manifestations were compared.Results HVS did not appear in 34 patients without cerebral infarction. It was observed in 43 of 92 patients with cerebral infarction. There were no significant differences in general clinical situation (age, with underlying diseases) between positive HVS group and negative HVS group (all P values>0.05). The mean infarction size was (4.0±1.1) lobes in positive HVS group and (2.5±0.9) lobes in negative HVS group. The scores less than or equal to 6 were found in 36 patients (83.7%, 36/43)in positive HVS group and in 13 patients (26.5%, 13/49) in negative HVS group based on DWI-ASPETS. It was significantly different between two groups (all P values<0.01). The muscle strength of patients was lower in positive HVS group than that in negative HVS group at admission (Z=1.978, P=0.048). MRA and /or CTA found 71.4%(25/35) patients had arterial occlusion and 28.6%(10/35) patients had arterial stenosis in positive HVS group, which was 45.5%(15/33) and 39.4%(13/33) in negative HVS group. It was significantly different between two groups (χ²=5.724, P＜0.05).Conclusions T₁WI HVS indicate arterial occlusion or severe stenosis, which can be used as an indicator of poor prognosis and is helpful to understand the cause of infarction, guide clinical treatment and judge prognosis.