摘要
目的 :用改良的线栓法大脑中动脉阻塞 (MCAO)模型 ,探讨急性脑缺血及再灌注的表观扩散系数 (ADC)成像特点。方法 :2 0只SD大白鼠 ,分为 4组 :A组 ( 8只 ) ,非再通组 ,B、C、D组 (各 4只 ) ,分别于MCAO 3 0min、1h、2h后再通 ,于不同时间点作ADC成像和T2 WI ,并测量感兴趣区的ADC、相对ADC (rADC)。结果 :MCAO后 15min即出现缺血区ADC下降 ,而T2 WI最早在栓塞后 2h出现异常。 6h内缺血区ADC及rADC呈不断下降趋势 ;MCAO 3 0min及 1h后再通 ,DWI上缺血区高信号完全或部分恢复正常 ,而MCAO 2h再通者 ,缺血区均无缩小 ;再通后可恢复正常的缺血组织的rADC明显低于未能恢复的核心区的rADC(P =0 .0 19)。结论 :ADC成像对急性脑缺血非常敏感 ,为研究脑缺血及再灌注提供定量的。
Objective:To assess acute cerebral ischemia and reperfusion with apparent diffusion coefficient (ADC) in a modified model of occlusion of middle cerebral artery (MCAO). Methods:20 rats were divided into 4 groups:group A (n=8), non-reperfusion;group B,C,D (n=4 for each),reperfusion at 30m,1h,2h following MCAO.All rats were examined with diffusion imaging and T 2WI at varying time point.ADC,relative ADC (rADC) were measured.Results:ADC decreased in the ipsilateral MCA territory at 15 minutes of MCAO,while hyperintensity was found on T 2WI as early as 2h after MCAO.ADC and rADC of abnormal area continuously declined within 6 hours after MCAO.After reperfusion,abnormal area on DWI recovered entirely or partially in group B and C,but not in group D.The rADCs of the area which could be recovered by reperfusion were significantly lower than those which not be salvaged by reperfusion.Conclusions:ADC imaging is highly sensitive to acute cerebral ischemia and serves as a quantitative,non-invasive imaging modality for evaluating acute cerebral ischemia and reperfusion.
出处
《放射学实践》
2000年第2期101-104,共4页
Radiologic Practice
关键词
急性脑缺血
磁共振成像
扩散研究
实验研究
Acute cerebral ischemia Magnetic resonance imaging Diffusion study Experimental study
