肝癌立体定向放射治疗后放射性肝损伤MRI表现的实验研究  

The Experimental Study on MR Imaging of Radiation-induced Hepatic Injuries After Stereotactic Radiotherapy in Hepatocellular Carcinoma

作　　者：吕国士[1] 许乙凯[1] 胡蓉 

机构地区：[1]广州市南方医院影像中心,广东广州510515 [2]北京空军总院

出　　处：《实用放射学杂志》2005年第4期343-346,共4页Journal of Practical Radiology

摘　　要：目的　评估肝癌立体定向放射治疗(SRT)后放射性肝损伤的动态影像学改变。方法　18只新西兰兔接种VX2 肉瘤后行40Gy的SRT,并随机分成3组:分别在放射治疗后3周、9周、20周行相同序列的常规和动态增强扫描。计算放射性肝损伤区域,正常肝组织平扫时T1WI、T2WI的信噪比(SNR),增强前后放射性肝损伤及正常肝组织强化率。结果　在T1WI和T2WI像上,放射性肝损伤区域SNR与正常肝组织SNR在SRT后3周对比无显著性差异, 9周与20周有显著性差异;SRT3周与9周、20周放射性肝损伤区域SNR相比有显著性差异, 9周和20周相比无显著性差异。放射性肝损伤区域强化率分别在动脉期3周组与20周相比有显著性差异, 9周和20周也有显著性差异。在静脉期和延迟期,强化率3周与9周、20周相比有显著性差异; 9周和20周无显著性差异。结论　MRI平扫和动态增强扫描可以准确反映放射性肝损伤各个阶段的病理变化。Objective To evaluate the dynamic imaging alteration of radiation-induced hepatic injuries after stereotactic radiotherapy (SRT) in hepatocellular carcinoma.Methods 18 healthy New Zealand white rabbits inoculated VX_2 carcinoma underwent 40 Gy SRT and divided into three groups randomly.The rabbits underwent identical plain and enhanced MR imaging after SRT 3 weeks,9 weeks and 20 weeks respectively. The signal-to-noise ratios of irradiation area and the surrounding normal liver on T_1WI and T_2WI imaging were calculated;The percentage enhancement of the hepatic injuried areas and the surrouding livers after Gd-DTPA enhanced was also calculated.Results After radiotherapy three weeks, the signal-to-noise ratios of irradiation areas on T_1WI and T_2WI were no difference between normal liver tissue and irradiation area; there were significant difference between normal liver tissues in radiotherapy nine weeks and twenty weeks; The difference in the signal-to-noise ratios of irradiation area were significant between after three weeks and nine weeks, twenty weeks. There were no difference in the signal-to-noise ratios of irradiation area between nine weeks and twenty weeks.The percentage enhancement of the hepatic injuries area have significant difference in arterial phase between three weeks and twenty weeks and between nine weeks and twenty weeks;The difference in portal and delay phase were significant between three weeks and nine weeks, twenty weeks, there were no difference between nine weeks and twenty weeks.Conclusion Dynamic enhanced and unenhanced MR imaging can reflect the pathological background of radiation-induced hepatic injuries in different phases.

关 键 词：放射性肝损伤 实验研究 磁共振成像 

分 类 号：R818.8[医药卫生—放射医学] R445.2[医药卫生—临床医学]