【摘要】 目的　分析新陈腔隙性脑白质梗死的T2 WI、扩散加权成像 (DWI)信号特点 ,比较两种梗死的病灶与脑白质、病灶与脑脊液对比度及表观扩散系数 (ADC) ,评价DWI在鉴别新陈腔隙性脑白质梗死方面的作用。方法　急性期腔隙性脑白质梗死患者 2 7例 ,选择 4 3例陈旧腔隙性脑白质梗死患者作对照。测量病灶、正常脑白质、脑脊液信号强度 ,计算病灶与脑白质、病灶与脑脊液的对比度。测量病灶、正常脑组织、脑脊液的ADC值并比较。结果　 (1)急性脑白质腔隙性梗死DWI呈高信号 ,ADC图呈等或低信号。DWI的病灶与脑白质、病灶与脑脊液对比度均优于T2 WI。 (2 )陈旧脑白质腔隙性梗死DWI呈等信号 ,ADC图呈高信号。DWI的病灶与脑白质对比度不如T2WI。 (3)DWI图像上 ,急性腔隙性脑白质梗死病灶与脑白质、病灶与脑脊液对比度明显高于陈旧病灶 ,ADC则明显低于陈旧病灶 ,有助于区分新陈腔隙性梗死。结论　DWI的检查时间短 ,诊断和鉴别意义大 ,建议在可能的情况下 ,将DWI作为急性卒中样发作患者的常规检查序列。更多还原

【Abstract】 Objective To analyze MRI T 2 WI and DWI signal features of acute and old cerebral lacunar infarcts,and to compare lesion vs. white matter contrast,lesion vs. CSF contrast and apparent diffusion coefficient (ADC) between the two types of infarcts. To evaluate the applicability of DWI in distinguishing recent lacunar infarcts from old lesions. Methods We prospectively studied 27 patients presenting with acute lacunar infarcts and compared them with 43 cases with classic old lacunar infarcts. We measured signal intensities of lesions,white matter and CSF from trace DWI images,and ADC from ADC maps. Results (1) Acute infarcts showed high intensity on DWI images,iso-intensity or hypo-intensity on ADC maps. Lesion vs white matter contrast of DWI was superior to T 2 WI. (2) Old infarcts showed iso-intensity or hypo-intensity on DWI images,and high intensity on ADC maps. Lesion vs. white matter contrast of DWI was inferior to T 2 WI. (3) Lesion vs. white matter and lesion vs. CSF contrast of acute infarct were superior to those of old infarcts on DWI,and the ADC of acute infarct lesions were much lower than that of old lesions. Conclusion Being an useful and time economic protocol,diffusion-weighted MRI might be considered as a routine protocol in the examination of stroke patients.更多还原