放射性肝损伤的动物实验研究

目的 探讨放射性肝损伤的生化指标、CT影像及病理学特点。方法 20只新西兰白兔随机分为4组:对照组,半肝放疗10、15和20 Gy组,放疗后3个月内监测肝功能、凝血功能,放疗后第3个月观察肝脏CT影像及病理变化特点。结果 20 Gy 组死亡3只,余组无死亡;10和15 Gy 组谷草转氨酶(AST)、总胆红素(TBIL)、直接胆红素(DBIL)于放疗后1个月起明显升高,碱性磷酸酶(ALP)放疗后下降,纤维蛋白原(FbgC)、凝血酶时间(TT)于放疗后1周升高显著,2周恢复至正常;CT增强扫描动脉期无强化,静脉期全肝广泛强化,肝内静脉显影不清,延迟期造影剂消退快;病理表现为随放疗剂量加大,肝静脉闭塞征、肝纤维化和胆管损伤表现越明显,同一放疗后肝脏照射区损伤较非照射区略重。结论 半肝放疗20 Gy死亡率明显增高,10和15 Gy后可引起肝功能改变及凝血功能一过性改变;CT表现为增强扫描显示强化减弱,肝静脉显影不清;随放疗剂量加大放射性肝纤维化、肝静脉闭塞征等表现加重。

Experimental study of biochemistry, CT images and pathologic changes in radiation induced liver injury

Objective To explore the appearance of radiation induced liver disease (RILD) on biochemical indicator, computer tomography(CT) and pathology. Methods Twenty rabbits were randomly divided into 4 groups as control group, 10, 15 and 20 Gy groups administered with semi-liver radiotherapy at different doses. Hepatic function and blood coagulation function indicators were monitored for 3 months after radiation. The appearance of CT images and pathology were observed 3 months post irradiation. Results After irradiation,20 Gy group had 3 rabbits died(3/5), while the other groups had no death. AST, TBIL and DBIL of groups B and C were increased at 1 month post irradiation, while ALP decreased. FbgC and TT were increased at 1 week post irradiation, then decreased to the normal level at 2 week. The CT image appearances were similar among 4 groups ,including no enhancement in artery phase, enhancement of whole liver in portal phase, the veins of liver unclear, and little enhancement in prolonged phase. The pathologic bases of RILD were VOD, collagen fiber aggradation and bile duct inflammation. The changes above-mentioned were more obvious when the radiation dose increased. Conclusions The death rate goes up apparently at the dose of 20 Gy for semi-liver radiotherapy. The doses of 10 and 15 Gy could induce hypohepatia and blood coagulation function to temporarily change. Appearances of CT are weakly enhanced and the veins of liver unclear. When the radiation dose increases, VOD and liver fibrosis become more serious.