大鼠放射性肾损伤模型制作及影像学评价

目的 研究大鼠放射性肾损伤影像学模型制作方法,研究早期放射性肾损伤病理改变及早期的CT、MRI特征。方法 48只SD大鼠随机分为对照组4组每组6只,照射组4组每组6只,左肾单次分割20 Gy电子线照射。照射后第4、12、24、36周分别行CT、MRI检测,观察影像学及病理改变。结果 CT、MRI均显示大鼠肾脏体积缩小,肾实质变薄等改变,MRI可显示皮髓质分界不清。病理检查显示4周后出现肾小球及肾小管损伤,并随时间逐渐加重。结论 SD大鼠单侧肾单次照射20 Gy可以制作放射性肾损伤模型并发生明显病理变化。CT、MRI均可作为诊断放射性肾损伤的方法,MRI优于CT检查。

Setting-up of Radiation-Induced Kidney Injury in Rat Model and Evaluation of Image Manifestations

Objective To study the setting-up methods of radiation-induced kidney injury in rat model, the pathological changes of in the early phase of radiation-induced kidney injury, and assess the diagnostic value of CT and MRI in the early phase of radiation-induced kidney injury. Methods Forty-eight Sprague Dawley rats were randomly divided into one normal control group and two experimental groups, and the experimental groups received a single dose of 20 Gy to the left kidney. Images of CT and MRI were obtained and pathological observation on the kidneys at 4, 12, 24, 36 weeks. Results CT、MRI findings including kidney atrophy and the thin of kidney parenchyma and the loss of corticomedullary differentiation were observed at the scheduled study. Radiation nephropathy was detected earlier with MRI than CT, and the sensitivity of MRI was higher than that of CT (P < 0.05). Pathological observation showed the morphological changes at 4 weeks after irradiation,including glomerular and tubular injury. An improvement in glomerular and tubular lesions was observed by 12、24、36 weeks after irradiation. Conclusion The radiation-induced kindey injury model can be setting up with the exposure of a single dose of 15 Gy radiation to the unilateral kidney of sprague dawley rats and morphological changes was observed. Early diagnosis of radiation-induced kidney injury can be performed with MRI scanning better than CT.