【作者】 沈钧康； 蒋震； 周剑影； 赵培峰； 张彩元； 陆雪官； 田野；

【机构】 苏州大学附属第二医院放射科；

【摘要】 目的探讨急性初期肝放射性损伤的MRI菲立磁增强表现及其病理基础。方法6只家兔经40Gy单次X射线半肝照射后第3天行肝区MRI T2WI平扫及T2WI菲立磁增强扫描,摘取受照区与非受照区肝组织,常规切片HE染色后光镜下观察组织学结构。选取1例再在电镜下观察细胞超微结构。对照分析MRI表现与上述组织学检查结果。结果所有家兔肝组织信号强度在平扫时均未发现变化;在菲立磁增强扫描时受照区与非受照区均较平扫时降低,但受照区信号强度均高于非受照区,两者间见明显分界线。家兔受照区与非受照区肝组织光镜下均未发现水肿、纤维化及炎症细胞浸润等异常改变,但受照区肝组织单位面积内含超顺磁性氧化铁(SPIO)颗粒的Kupffet‘细胞数明显减少。电镜下受照区肝组织却发现亚细胞水平变化;肝细胞、Kupffer细胞内线粒体明显肿胀及局部胞浆内空泡样变。结论T2WI菲立磁增强扫描在照射后短时间内(照射后第3天)即可检出肝放射性损伤改变,并能提供直观、精确的影像学依据,对放射性肝损伤的早期发现具有重要的临床意义。更多还原

【Abstract】 Objective To evaluate the relationship between the early histopathologic findings of radiation on liver and superparamagnetic iron oxide (SPIO) contrast-enhanced MR imaging. Methods The left sides of the livers of 6 anesthetized rabbits were irradiated with X-rays(40Gy). On the 3rd days postirradiation, conventional MR imaging (TSE-T2WI) and SPIO contrast-enhanced MR imaging (TSE-T2WI) were performed and specimens were obtained. Results The signal intensity of both irradiated and non-irradiated liver were normal and uniform on T2WI imaging without SPIO. On SPIO-enhanced T2WI imaging, both portions of liver decreased in signal intensity. However, the signal intensity of the irradiated portion of the liver were higher than the non-irradiated portion, and the margins of the irradiated portion were demarcated. All specimens seemed to be normal, and no evidence of edema, fibrosis, congestion, infiltration of inflammatory cells was found by light microscopy. Nevertheless, the number of Kupffer cells containing stained iron particles was less in the irradiated liver than in the non-irradiated liver. Furthermore, the swelling of mitochondria and vacuolization in the hypatocytes and Kupffer cells of the irradiated liver were found by the electron microscopy. Conclusion MRI SPIO-en-hanced T2WI can detect the early effects of radiation on the liver after irradiation very shot time (3 days).更多还原