磁共振弥散加权成像诊断急性脑梗死的价值

目的：评价弥散加权成像（DWI）在急性脑梗死诊断中的应用价值。方法：22例脑梗死患者（超急性2例，急性期12例，亚急性期8例）经DWI成像、T1WI、T2WI及FLAIR检查，比较不同序列间病灶的信号强度表现及病灶数目。结果：单纯脑梗死DWI均表现为高信号，伴有出血时表现为混杂信号；而T2WI/FLAIR检查中2例超急性患者未显著责任病灶，急性期内仅2例表现为高信号，其余表现为略高信号或等信号。综合比较三种检查中病灶与对侧相应部位信号强度，DWI组与FLAIR组及T2WI组间差别均有显著意义（方差分析PFLAR=0.001，PT2WI=0.038），DWI优于FLAIR及T2WI。本组共有9例于T2WI显示为多处病灶，而DWI均为单发病灶，且单发病灶部位与患者的症状及体征相符。结论：DWI对于急性脑梗死比T2WI及FLAIR具有更高的敏感性；有助于多次梗死患者急性责任病灶的检出；有助于诊断出血性脑梗死。

The Value of MR Diffusion-Weighted Imaging in Diagnosing Acute Cerebral Infarction

Objective To evaluate diffusion-weighted imaging(DWI) in the diagnosis of acute cerebral infarction.Methods DWI features in 22 patients with cerebral infarctions(2 superacute, 12 acute, 8 subacute) were compared with FSE T2WI and FLAIR.Results Cerebral infarction all showed hyper-intensity on DWI,and showed hetero-intensity in case of hemorrhage.Two superacute patients showed nothing related on T2WI/FLAIR. In acute cases , except 2 patents showed hyper-intensity, all showed lower-high intensity or equal intensity.By comprehensive contrasts on the ratios of lesions and the counterparts based on three different means, DWI is prior to T2WI and FLAIR (ANOVA P FLAIR=0.001,P T2WI=0.038).9 patients who appeared as multi-lesions by T2WI just showed one high lesion by DWI, which related to the acute symptom strongly.Conclusion Due to its highest sensitivity for acute cerebral infarction, DWI is helpful in differentiating acute lesion from chronic infarction, and in the diagnosis of hemorrhagic infarctions as well.