摘要
目的应用多模式MR成像观察兔蛛网膜下腔出血(SAH)后急性期是否存在脑梗死或一过性缺血性脑卒中(损伤)的影像学表现,探讨SAH后急性期是否存在脑损伤及其可能的发病机制,为诊断和治疗SAH提供理论依据。方法应用前交叉池注血法制作兔SAH模型。8只新西兰大白兔随机分为2组:A组(模型组,n=4),B组(对照组,n=4)。使用常规MRI序列、3D TOF MRA及DWI,获取兔脑T1WI、T2WI、FLAIR及颅内大血管序列图像,分析模型组和对照组动物术前及术后5 min、30 min、45 min、60 min、90 min时大脑皮层及基底核区ADC图及水分子弥散受限动态变化曲线,测量ADC值及血管直径。结果模型组注血后5～60 min ADC下降脑区范围逐渐扩大,跨血管分布,双侧大脑皮层ADC值均明显低于正常,90 min有所回升,ADC值差异有统计学意义(P<0.05)。双侧基底核区ADC值与正常无明显差异(P>0.05)。对照组动物各观察时间点与术前相比,双侧大脑皮层及基底核区ADC值差异无统计学意义(P>0.05)。MRA可以显示颈部大动脉的形态学改变,但未能显示颅内动脉主干。结论 SAH后急性期大脑皮层存在脑损伤,这种损伤并非为急性脑梗死,血液及其崩解代谢产物的直接细胞毒作用或一过性缺血性脑卒中造成皮层组织细胞的代谢紊乱,尚需进一步实验研究证实。
Objective To investigate the cerebral injury at the acute stage after the subarachnoid hemorrhage（SAH） and its possible mechanism in rabbits with multi-mode MRI techniques and provide the theoretical basis for therapy and prevention beforehand by observing the dynamic alterations of water diffusion before and after SAH.Methods Rabbit SAH model was established by blood injection into the pre-chiasmatic cistern.Eight adult New-Zealand rabbits were randomly assigned into 2 groups： A group（model group,n=4） and B group（control group,n=4）.At 5min,30min,45min,60min and 90min before and after operation,T1WI、T2WI、FLAIR、3D-TOF MRA and MR diffusion weighted imaging（MR DWI） series were individually performed between model group and control group.The ADC maps and the dynamic alteration change curves were obtained,and the related parameters were calculated in cerebral and basal ganglia.All data was analyzed by SPSS 11.0 statistical software package.One-way ANOVA were performed among groups.Differences with P〈0.05 were considered significant.Results In model group,the abnormal diffusion area spread gradually and bestrode blood vessel from 5min to 60min after blood injection,and the ADC values in bilateral cerebral cortex were obviously lower than those in normal before operation,which was recovered but still lower than the normal at 90min.ADC values in bilateral cerebral cortex had significantly difference from the normal（P〈0.05）,which were on the contrary in bilateral basal ganglia（P〉0.05）.In control group,no significant differences were demonstrated compared with normal before operation in bilateral cerebral cortex and basal ganglia at the same observing time point（P〉0.05）.The main trunk of the intracal artery wasn＇t observed with MRA,which were on the contrary in the main artery of neck.Conclusion There is cerebral injury at acute stage after SAH,which cannot be correlated with the decrease of cerebral microcirculation＇s hemodynamic parameters.The toxic effect of blood clots di
出处
《安徽医学》
2011年第1期76-79,共4页
Anhui Medical Journal
关键词
蛛网膜下腔出血
脑血管痉挛
磁共振成像
弥散加权成像
Subarachnoid haemorrhage
Cerebral vasospasm
Magnetic resonance imaging
Diffusion weighted imaging
