【摘要】 目的 研究脑梗死病灶在DWI及T2WI上的变化规律，并探讨DWI的应用价值。方法 采集48例脑梗死患者MRI(包括DWI)信息，测量rADC、rSIDWI、rSIT2WI及SDWI/ST2WI值，绘出它们随时间变化的直方图。结果 急性脑梗死发病后rADC降低，之后逐步升高并超过对侧。早期脑梗死病变rSIDWI值较高，至晚期则降低，而rSIT2WI则升高。DWI及T2WI上对面积测量的比值在各个时期间无明显统计学差异。结论 脑梗死病灶在DWI及T2WI上有一定的变化规律，DWI能快速、准确地诊断急性、亚急性脑梗死。

    【关键词】 脑梗死；弥散加权成像；磁共振成像

    Evalution of apparent diffusion coefficient,diffusion-weighted and T2-weighted signal intensity of cerebral infarction

    XU Ji-feng,ZHAN Song-hua,ZHANG An-jun,et al.Department of Radiology,Shuguang Hospital,Shanghai 200020，China

    【Abstract】 Objective To study the regularities of cerebral infarction lesions on DWI and T2WI,and evaluate the role of DWI.Methods To get the MRI(include DWI) information of 48 patients with cerebral infarction,rADC、rSIDWI、rSIT2WI and SDWI/ST2WI were measured and time-intensity map was drawn.Results The value of rADC decreased in acute cerebral infarction,then it increased step by step and was higher than the value of rADC in the other side. The value of rSIDWI was higher in early stage,and it decreased thereafter.On the other hand,the value of rSIT2WI increased. The infarct areas were measured on DWI and T2WI,their rates were not statically different among every stage.Conclusion Cerebral infarction lesions have specific evolution on DWI and T2WI,DWI can diagnose acute and subacute stage cerebral infarction quickly and accurately. ......