PWI和DWI对短暂性脑缺血发作的诊断价值

Perfusion and diffusion-weighted MR imaging of the transient ischemic attacks

目的观察弥散加权成像(DWI)、灌注加权成像(PWI)对短暂性脑缺血发作(TIA)的诊断价值。方法 34例TIA患者分别行常规头MRI(T1WI、T2WI)、DWI、PWI检查并进行分析。结果全部病例发现9例(26.5%)DWI异常,且T2WI与DWI均显示在同一部位;PWI显示23例(67.6%)异常;PWI异常率明显高于DWI异常(P=0.003);综合磁共振血管成像(MRA)、数字减影脑血管造影(DSA)及颈动脉超声联合经颅多普勒超声(TCD)(简称超声)检测判定责任血管病变:正常-轻度狭窄21例(61.8%),中重度狭窄13例(38.2%)。责任血管病变程度与PWI异常差异有统计学意义。结论大部分TIA间期的脑血流灌注异常,部分TIA已经发生脑梗死。应重视TIA的处理以防止TIA复发及脑缺血进展。

Objective To investigate the diagnostic values of DWI and PWI in patients with transient ischemic attack(TIA).Methods Thirty-four patients with internal carotid system TIAs were examined by MR(T1WI,T2WI),DWI,PWI.All the results of the above examinations were analyzed by SPSS version 11.5 software.Results Of 34 TIA patients,9 cases(26.5%)demonstrated neuroanatomically relevant focal abnormalities on DWI.They all did exhibit T2WI abnormalities in the same regions as DWI alterations.Abnormal perfusion rate of PWI were 63.5%.There was statistically difference between abnormal rate of PWI and DWI(P=0.003).MRA,DSA and TCD were applied to evaluate the cerebral feeding arterial lesions.Thirteen patients(38.2%) had intracranial arteries moderate-severe stenosis.Some 61.8%(21/34) of the cases had arteries mild stenosis or normal.There was significantly difference between abnormal perfusion rate of PWI and arteries stenosis.Conclusion A substantial proportion of patients with TIAs have reduction of regional cerebral blood flow in the intermittent phase.Some patients with TIAs experience cerebral infarction.The treatment of TIA should be emphasized in order to prevent TIA relapse and permanent ischemic injury.