联合磁共振弥散加权及灌注加权成像定量研究急性脑梗死可存活区  

The final survival area in acute cerebral infarction quantitated by diffusion-weighted imaging and perfusion-weighted imaging

作　　者：李欢欢[1] 黄丙仓[1,2] 弋春燕 武刚[1] 张宏艳[2] 蒋伟[2] 杨晓丹[2] 

机构地区：[1]复旦大学附属中山医院青浦分院(上海市青浦区中心医院)放射科,上海201700 [2]上海市浦东新区公利医院医学影像科,上海200135

出　　处：《肿瘤影像学》2013年第1期23-26,共4页Oncoradiology

基　　金：上海市科技发展基金(No:114119a9700);上海市浦东新区科技发展基金(No:PKJ2011-Y10)

摘　　要：目的探讨应用磁共振弥散加权和灌注加权成像(DWI和PWI)技术判断急性脑梗死后可存活脑组织的范围及特征,从而影像学定位脑梗死可存活区,确定适合溶栓治疗的患者,并预测可存活区域。方法对76例发病24 h以内的急性脑梗死患者行常规MRI、DWI、PWI,根据患者就诊治疗时间的不同分为3组(分别在发病3 h、6 h、24 h内就诊)。通过PWI与DWI不匹配区确定缺血半暗带(IP)区,追踪1个月后再次复查MRI常规、DWI。复查时T2高信号区定为最终梗死区,初检PWI异常区减去最终梗死区即为可存活区。确定可存活区的表观弥散系数(ADC)范围,及其与梗死中心区、IP区的关系。结果 6 h内就诊的患者普遍存在IP区(PWI>DWI),7~24 h就诊的患者大部分病灶PWI≤DWI,部分病灶依然存在IP区。可存活区与IP区ADC值差异无统计学意义;可存活面积大于IP区且与IP区面积呈正相关,可存活区面积随就诊时间延长而减小(差异有统计学意义)。结论 IP区存在的时间界限约为6 h,部分病例可延长至8~24h;在IP区存在的情况下,可存活区面积与IP区面积呈正相关,可存活区面积>IP区面积。Objective To evaluate the characteristics of the final survival area in cerebral infraction by diffusionweighted imaging(DWI) and perfusion-weighted imaging(PWI),and to locate the brain’s survival area.Thus the suitable patients for thrombolytic treatment can be determined.Methods Conventional MRI and PWI and MRS were performed in 76 patients clinically diagnosed with acute cerebral infarction within 24 h.The patients were divided into groups A,B and C according to the time from onset to being admitted to hospital within 3 h,6 h,and 24 h,respectively.The ischemic penumbra(IP) area was determined by PWI/DWI mismatch.All the patients were detected by conventional MRI and DWI a month later when a high signal density area on T2 was considered as final infarct area.The abnormal area on initial PWI minus the final infarct area was considered as the final survival area.According to these,the range of apparent diffusion coefficient(ADC) value in the survival area was determined and the relationship between the survival area and infarct center and ischemic penumbra area was showed.Results Most patients in groups A and B had ischemic penumbra area.A small part of the patients in group C had ischemic penumbra area and most lesions showed PWI≤DWI.There was no significant difference in ADC values between the final survival area and ischemic penumbra area.The survival area was larger than ischemic penumbra area,and was positively correlated with ischemic penumbra area.As time going on,the survival area became smaller(the difference was statistically significant).Conclusion The existence of ischemic penumbra area lasts 6 h or so.In some cases it can be extended to 8 h even 24 h.The survival area and ischemic penumbra area are positively correlated in the presence of ischemic penumbra area,and the survival area is larger than ischemic penumbra area.

关 键 词：磁共振成像 脑梗死 缺血半暗带 可存活区 

分 类 号：R445.2[医药卫生—影像医学与核医学] R743.3[医药卫生—诊断学]