早期脑梗死的临床与磁共振弥散加权成像

Clinicals and diffusion weighted imagine in acute cerebral in farction patient

目的 从临床角度探讨磁共振弥散加权成像(diffusion weighted imagine ,DWI)对早期脑梗死的诊断价值和确定DWI在区分常规MRI上所示的多发梗死灶中急性和非急性梗死方面的能力。方法 60例脑梗死均进行MRI常规程序及DWI程序检查，并由4位经验丰富的医师在不了解患者临床体征的情况下进行阅片、记录出病变所在的详细的神经解剖部位，对同一层面所有的磁共振像进行比较，重点分析信号强度和病灶大小。数据经统计学分析。结果 DWI对超急性及急性期脑梗死可显示T2加权像不能显示的病灶，并随时间延长显影范围逐渐增大。在T2加权像上可显示的病灶中，DWI可更清楚、更全面地显示病灶，大于T2病灶。在急性后期，常规MRI及DWI均有较清晰的影像学改变。恢复期及慢性期，DWI影像学逐渐改变变成等信号、杂信号，部分为囊性信号，且不易显示病灶。结论 DWI能非常可靠地显示超急性及急性脑梗死，而在急性后期及慢性期不如T2WI。其具有区分急性和非急性脑梗死的能力。

Objective To probe into the clinical value of diffusion weighted imagine (DWI) in diagnosing the early cerebral infarction and determine its capability in differenting the acute and un-acute lesions which were showed in routine MRI. Meanwhile, have a try to study the ischemic penumbr a. Method 60 patients with cerebral infarction underwent routine MRI sequence and DWI sequence.Readings were performed jointly by 4 wellexperienced neuroradiologists who were unfamiliar with the cases. The neuroanato mically relevant lesions were identified.All images within one slice were compared, especially the signal intensity and the lesion areas. Result Ultra-acute and acute infarction could be showed on DWI which may not be showed on T2 weighted imaging and the volume increases with increasing symptom duration. The lesions that had showed on T2 image is clearly shown on DWI, and was larger than that on T2 image. At late stage, routine MRI and DWI clearly demo nstrated the ischemic abnormalitis. During recovery stage and chronic stage, the l esions on DWI change to equal or complex signal, partly cyst signal. Conclusion DWI is reliable in diagnosis ultra acute or a cute infarction but during recovery and chronic stage, DWI is less sensitive tha n T2 image. It can differ acute infarction from un-acute infarction.