兔喉部^(125)I粒子植入术后周围辐射剂量的实验研究

The surrounding radiation dose of iodine-125 seeds on normal larynx tissue in rabbits

目的:监测放射性^(125)I粒子植入家兔正常喉组织后不同时间周围辐射剂量的变化,从辐射防护角度探讨其临床应用的安全性。方法:健康雄性普通级新西兰家兔60只,重2.15~2.30kg,随机分为7d组、1个月组、2个月组、4个月组及对照组,每组12只。分别将3粒活度为0.8mCi/粒、半衰期60.2d的放射性^(125)I粒子植入实验组家兔右侧第一气管环旁。测量实验组4个月亚组植入粒子后不同时间、不同距离的周围辐射剂量,对结果进行统计学处理。结果:随着与粒源距离的增加及植入后时间的延长,周围辐射剂量减少,且随着距离的增加,周围辐射剂量下降缓慢,在距离粒源1m处,测得剂量为室内天然本底辐射剂量。结论:放射性^(125)I粒子组织间植入治疗临床应用易于防护,其周围密切接触者是安全的。

Objective：To monitor the change of the radiation dose of the rabbits which were implanted rasioac- rive ^125I seed into the normal laryngeal tiseue at different time,and to evaluate the safety of radiation protection. Method： Sixty New Zwaland rabbits, weighing 2.15-- 2.30 kg, were randomly divided into 5 groups ： 7 d, 1month, 2 month,4 month group and the control group, 12 rabbits in each group Iodine-125 of 0.8 mCi were implanted into the right side of the first trachea ring. At the different time and different distance, the surrounding radiation dose was measured after 4 months of implanting. The results were analyzed in statistics. Result：With the increase of the distance and the prolong of the time, the radiation dose was decreasing, and with the increase of distance, the radia- tion dose decreased slowly. At the site of 1 meter from the seeds, the detected dose is close to the natural back- ground radiation dose. Conclusion：The clinical application of radioactive ^125I seed interstitial implant is easy to pro- tected,the surrounding close contacts is satety.