3d 龄新生鼠缺氧缺血性脑损伤M RI 表现的实验研究

目的：研究新生大鼠缺氧缺血性脑损伤（HIBD）MR扩散加权成像（DWI）的变化，探讨其与TTC染色变化的关系。方法采用结扎大鼠左颈总动脉法，建立3组不同程度 HIBD动物模型；于不同时间点（6～12 h、12～24 h、3 d、7 d）行DWI扫描；另取各模型组新生鼠分别于12 h、24 h、3 d、7 d取新鲜脑组织行T TC染色，观察其与DWI的关系。结果3模型组病变部位主要分布在左侧皮层及皮层下区，随着缺氧时间的延长，左侧海马、侧脑室旁、丘脑也有不同程度受累，个别病例出现右侧皮层受累。T TC染色于3 d出现阳性结果，其失染区与DWI异常信号区基本一致。结论 DWI可早期评价 HIBD的病变范围；HIBD早期损伤部位主要分布在皮层及皮层下区。

The experimental study of 3-day-old newborn rats with hypoxic-ischemic brain damage in MRI

Objective To explore the changes of MR diffusion imaging (DWI) appearance in newborn rats with hypoxic‐ischemic brain damage(HIBD) ,and its relationship with the changes of Triphenyl tetrazolium chloride (TTC) staining .Methods Using liga‐tion of the left carotid artery method to establish three different degrees of HIBD animal models ;DWI was performed at each time point(6-12 h ,12-24 h ,3 d ,7 d);Fresh brain tissue taken from another model groups of newborn rats in 12 h ,24 h ,3 d ,7 d were staining in TTC ,then we observed its relationship with DWI .Results The lesion location of three model groups mainly distributed in the left side of cortex and subcortical region ,with prolonged hypoxia time ,hippocampus ,lateral side white matter ,thalamus were also have varying degrees of involvement .The right side of the cortex and subcortical in some cases involved .TTC staining showed posi‐tive results in 3 d ,its loss stained area were consistent with DWI abnormal signal area .Conclusion DWI can be evaluation of HIBD lesions early .The early lesions of HIBD mainly distributed in the left side of cortex and subcortical region .