磁共振弥散加权成像对急性脑梗死的诊断价值

目的：探讨磁共振弥散加权成像(DWI)在急性脑梗死中临床诊断价值和区分多发梗死灶中急性和非急性方面的能力。方法：对56例脑梗死发病时间不同的病例行常规MR及DWI程序检查，对同一层面所有的磁共振成像进行比较，重点分析信号强度及病灶大小，数据做统计分析。结果：DWI对超急性及急性脑梗死可显示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，表现弥散系数(ADC值)明显下降。急性后期DWI显示病灶不如T2加权像，ADC值接近或高于正常。结论：脑梗死的DWI信号和ADC值变化具有特征性的时间演变规律，DWI能非常可靠地显示超急性和急性脑梗死，具有区分急性和非急性脑梗死的临床诊断价值。

A Clinical Study of Diffusion Weighted Imagine In Diagnosis of Acute Cerebral Infarction

objective: To explore the clinical value of diffusion weighted imagine (DWI) in diagnosis of the acute cerebral infarction.Methods:Fifty-six patients with cerebral infarction underwent routine MRI sequence and DWI sequence.The neuroanatomically relevant lesions were identified.All images within one slice were compared,especially the signal intensity and the lesion areas.Results:Ultra-acute and acute infarction could be showed on DWI which may not be showed on T2 weighted imaging and the volume increaseed with increases of symptom duration.At late stage,the lesions showed on DWI were less sensitive than T2 image, ADC was near or higher than normal.Conclusion:The specific time course of signal intensity changes and the ADC abnormality after cerebral infarction on DWI,DWI is reliable in diagnosis of ultra-cute or acute infarction.It can differ acute infarction from unacute infarction.