摘要目的 观察锂-匹罗卡品诱导大鼠癫痫模型的急性期MRI表现,探讨癫痫急性期的病理生理变化.方法 22只雄性SD大鼠按照随机数字表法分为对照组(n=9)和模型组(n=13),模型组大鼠腹腔注射氯化锂及匹罗卡品造模,对照组大鼠腹腔注射等体积生理盐水.采用MRI平扫及扩散加权成像(DWI)观察2组大鼠双侧海马、梨状皮层、内嗅皮层、感觉皮层的表现并比较表观扩散系数(ADC)差异.结果 4只模型组大鼠在常规T2WI序列上信号增高,6只在DWI上信号增高.与T2WI相比,DWI图像显示范围更广,信号增高区域主要分布于感觉皮层、梨状皮层+内嗅皮层.与对照组大鼠比较,模型组大鼠双侧梨状皮层+内嗅皮层、感觉皮层的ADC值均明显降低,差异均有统计学意义(P<0.05).2组大鼠双侧海马的ADC值差异均无统计学意义(P>0.05).结论 MRI检查可以反映癫痫大鼠急性期的脑组织改变,表现为多个脑区信号异常,其中感觉皮层、梨状皮层和内嗅皮层的改变可能早于海马.

abstractsObjective To investigate the MR imaging findings of Li-pilocarpine-induced acute epilepsy rats and explore the pathophysiological changes of acute epilepsy rats.Methods Twenty-two SD rats were randomly divided into control group (n=9) and model group (n=13). Rats in the model group were intraperitoneally injected with lithium chloride and pilocarpine, while rats in the control group were given equal volume normal saline. All rats were given MR imaging plain scan and diffusion weighted imaging (DWI). The images of rats of the two groups were compared, and the differences of apparent diffusion coefficient (ADC) of the hippocampus, piriform cortex, entorhinal cortex and sensory cortex were compared.Results Four rats in the model group show hyperintensity in T2 weighted imaging and 6 rats in the model group showed hyperintensity in DWI; as compared with T2 weighted imaging, DWI has wider display ranges, mainly distributed in the sensory cortex, and piriform cortex+entorhinal cortex. As compared with those in the control group, the ADC values in sensory cortex and piriform cortex+entorhinal cortex of model group significantly decreased (P<0.05). There were no statistical differences of ADC values in the hippocampus between two groups (P>0.05).Conclusion Multiple regions are involved in acute epilepsy rats, which maybe shown by MR imaging; changes in the somatosensory cortex and piriform cortex+entorhinal cortex may occur before those in the hippocampus.