射频热凝家兔肝组织的热效应观察

The thermal effect of cool-tip radiofrequency generator on liver tissue of rabbit

目的研究射频热凝家兔肝组织的热效应范围,并观察肝细胞、肝内动脉、静脉及胆管组织的损伤情况。方法将40只家兔随机分为2组(实验组与对照组,每组20只),均分别剖腹暴露肝脏,于实验组家兔肝膈面插入射频针并给予射频热凝处理,对照组家兔手术操作与实验组相同,但不给予射频热凝处理。2组家兔分别于术后1,5,10,15d各处死5只,取肝脏不同部位进行常规切片染色,观察肝细胞、动脉、静脉及胆管组织的损伤情况。采用TUNEL法检测肝细胞、胆管上皮细胞的凋亡率,并测定家兔术前、术后血清GPT、T-BIL及D-BIL水平。结果通过组织学观察,发现该射频热凝治疗仪(单电极)对家兔肝组织的最大热效应损伤半径为2.5cm,在坏死区域内可见肝细胞、血管及胆管等均有程度不一的损伤。距凝固坏死区外边缘2.0cm范围内的肝细胞、胆管上皮细胞的凋亡指数均高于对照组相应部位细胞,差异有统计学意义(P<0.01);另外还发现实验组家兔肝细胞的凋亡指数也高于同区域胆管上皮细胞凋亡指数(P<0.01)。结论对射频热效应耐受性由高至低排列依次为:胆管>动脉>静脉>肝细胞,正常家兔肝细胞对射频热效应的敏感性大于胆管上皮细胞,细胞凋亡可能与射频热效应相关,即射频热凝能引发肝细胞、胆管上皮细胞凋亡。

Objective To investigate the ablation range of Cool-tip radiofrequency generator and its thermal effect on liver ceils, intrahepatic artery, vein and biliary duct. Methods Forty healthy New Zealand rabbits were divided into an experimental group and a control group. The rabbits of the experimental group were treated with one session of radio-frequency delivered by Cool-tip radio-frequency generator and killed at 1,5,10, 15 days after the treatment. Histologic manifestations of the liver ceils, intrahepatic artery, vein and biliary duct were characterized under light microscope. Apoptosis detected by TUNEL served as the index of thermosensitivity. GPT,T-BIL, D-BIL level were also tested before and after the treatment. Results The ablation radius of the Cool-tip radio-frequency lesion generator was 2.5 cm. There were lesions of different degrees in liver cells, intrahepatic artery, vein and biliary duct. The apoptosis index of hepatocytes and biliary epithelial cells within 2 cm to the edge of coagulated region in the experimental group was higher than those in the control group（P 〈 0.01 ）. As well, the poptosis index of hepatocytes was also higher than that of biliary epithelial cells（P 〈 0.01 ）. Conclusion The tolerance to radio-frequency ablation of various tissues from high to low was as bile duct 〉 artery 〉 vein 〉 liver ceils. The thermosensitivity of the normal rabbit hepatocyte was higher than that of biliary epithelial ceils to radiofrequency ablation. Apoptosis was correlated to the thermal effect induced by RFA.