缺血性脑卒中早期脑血清酶及MR T_2 WI动态改变的实验研究  

Experimental Study on the Dynamic Variations of Cerebral Serumal Enzymes and MR T_2 WI during Early Ischemic Stroke

作　　者：朱晓黎[1] 丁乙[1] 刘一之[1] 倪才方[1] 

机构地区：[1]苏州医学院附属第一医院影像中心,215006

出　　处：《临床放射学杂志》2000年第9期588-592,共5页Journal of Clinical Radiology

摘　　要：目的　通过建立兔缺血性脑卒中模型研究早期脑缺血后脑血清肌酸磷酸激酶 (CPK)、乳酸脱氢酶 (LDH)、门冬氨酸转氨酶(AST)活性与MRT2 WI动态改变及其相关性。材料与方法　 5 2只兔分 3组 :缺血组 ( 3 8只 ) ,对照组 ( 6只 ) ,病理观察组 ( 8只 )。通过建立改进的自体血凝块栓塞法兔缺血模型 ,分别测定不同时间点脑血清CPK、LDH、AST的活性改变以及MRT2 WI信号强度改变 ,计算结果并进行统计学处理。结果　缺血组脑血清CPK于缺血后 2h即开始升高 ,而LDH、AST则在缺血后 4h开始升高 ,并均于2 4h达到高峰 ,分别为 5 2 98.0± 810 .0IU/L、3 2 8.7± 5 7.4IU/L、5 9.7± 10 .6IU/L ,48、72h后逐渐下降 ,但仍较正常高 (P <0 .0 1)。MRT2 WI则在 4h时可清楚显示缺血区高信号改变 ,其SI增强百分比为 16.8± 2 .72 % ,较栓塞前 ( 10 .2 6± 3 .84% )及对照组 ( 10 .68±2 .5 7% )为高 (P <0 .0 1) ,且在 2 4h时达到高峰。在 48、72hSI信号强度百分比较 2 4h已有下降 ,但仍呈高信号改变。缺血区SI增强百分比与脑血清CPK、LDH、AST动态改变呈明显正相关 (r为 0 .90、0 .93、0 .94)。结论　研究脑血清CPK、LDH、AST酶活性的动态改变及MRT2 WI缺血灶SI信号改变有助于缺血性脑卒中的早期诊断 。Objective To investigate the dynamic variations and the relationship between the enzyme activity (CPK, LDH, AST) in cerebral serum and MR T 2WI of the early ischemic stroke with cerebral ischemic model on rabbit.Materials and Methods Fifty two rabbits were divided into 3 groups: inschemic group (n=38), control group (n=6) and histopathologic group (n=8). Ischemic cerebral stroke rabbit model was established with auto coagulated clot, cerebral serumal enzymes activity of CPK, LDH and AST were estimated at different time point and the dynamic variations of the signal intensity on MR T 2WI were observed, the results were statistically analyzed.Results CPK in ischemia group began to increase as early as 2 hours after ischemic ictus, while LDH and AST began to increase in 4 hours. The values were 5298.0±810.0 IU/L, 328.5± 57.4 IU/L and 59.7±10.6 IU/L, respectively. They began to decrease at 48 and 72 hours after ischemic ictus, though still higher than those of normal group (P<0.01). The high signal intensity of ischemic foci was clearly delineated on MR T 2WI at 4 hours, with the SI enhancement percentage of 16.09 ±6.72%, which was higher than 10.26±3.84% of pre embolization and 10.68±2.57% of control group (P<0.01). SI enhancement percentage reached its peak value at 24 hours. At 48 and 72 hours the SI enhancement percentage became lower than that of 24 hours, though still remained high signal contrast foci. SI enhancement percentage bore a significant positive relationship to the dynamic variations of cerebral serumal enzymes of CPK, LDH and AST, with r of 0.90, 0.93 and 0.94, respectively.Conclusion The investigation of the dynamic variations of cerebral serumal enzymes activity of CPK, LDH, AST and SI signal changes of ischemia foci is helpful for the diagnosis of early ischemic cerebral stroke, beside it provides objective index for judging the therapeutic effect of thrombolysis therapy and cerebral protective agent.

关 键 词：缺血性脑卒中 脑血清酶 磁共振成像 CPK LDH 

分 类 号：R446.1[医药卫生—诊断学]