神经保护剂干预实验性缺血半暗带演变规律的磁共振动态观察  

Application of Magnetic Resonance Imaging on Ischemic Penumbra of Rats Controlled by Neuroprotective Additive

作　　者：张雪君[1] 孙志华[2] 姜琳[1] 张云亭[2] 

机构地区：[1]天津医科大学医学影像学院,天津300203 [2]天津医科大学总医院,天津300052

出　　处：《中国医学影像学杂志》2011年第7期489-494,共6页Chinese Journal of Medical Imaging

基　　金：天津市自然科学基金(09JCYB-JC11600);图家自然科学基金(30370434)资助

摘　　要：目的研究大鼠急性脑缺血模型缺血半暗带(IP)的扩散加权成像(DWI)和扩散张量成像(DTI)演变规律。材料与方法制作大鼠大脑中动脉闭塞(MCAO)缺血模型。分为应用神经保护剂组及对照组。在0.5～48h内行T2WI(T2WI)、DWI及DTI检查,测定缺血灶不同部位的表观弥散系数(ADC)、平均弥散系数(DCavg)、部分各向异性(FA)值,计算病侧与对侧正常组织的相对值rADC、rDCavg、rFA值。结果神经保护剂组与对照组的相对(r)ADC值、rDCavg值、rFA值,2h以内组间各ROI间差异均无统计学意义(P>0.05)。3～6h以后,两组间差异有统计学意义(P<0.01)。24h、48h两组间差异无统计学意义(P>0.05)。结论大鼠MCAO模型缺血灶ADC、DCavg、FA值具有特征性演变规律;IP存在的时间窗为9～12h,应用神经保护剂后IP存在时间可延长至24h。Purpose To study the evolution of ischemic penumbra（IP） on diffusion weighted imaging（DWI） and diffusion tensor imaging（DTI） in a rat model of acute cerebral ischemia.Materials and Methods Rats were operated to develop middle cerebral artery occlusion model and were divided into a permanent ischemia group and a neuroprotective additive-treated group.T2WI,DWI and DTI were performed within 0.5 ～ 48 hours.The values of apparent diffusion coeff icient（ADC）,average diffusion coefficient（DCavg） and fractional anisotropy（FA） in different areas of ischemic region were measured,and the ratios of lesion to contralateral region were calculated as rADC,rDCavg,rFA.Results Between the permanent ischemia group and the neuroprotective additive-treated group,there was no significant difference of rADC,rDCavg,and rFA in all ROIs within 2 hours（P 〉0.05）.After 3 to 6 hours,there was significant difference of the parameters between the two groups（P 〈 0.01）.No significance of the parameters was seen at 24h and 48h between the two groups（P 〉 0.05）.Conclusions It had characteristic evolution of ADC,DCavg and FA in the rat model of acute cerebral ischemia.The present time window of ischemia penumbra may be 9 ～ 12h.After treated with neuroprotectiveadditive,the time window of IP may last to 24h.

关 键 词：脑缺血 磁共振成像 神经保护药 

分 类 号：R743.9[医药卫生—神经病学与精神病学]