103Pd放射性支架持续照射犬胆管的放射性损伤的实验研究

目的　寻找动物胆管金属内支架植入方法 ,观察动物胆管植入1 0 3 Pd放射性支架 ,胆管腔内照射的放射性损伤。方法　实验动物为雄性健康杂种犬 ,体重 1 5～ 2 0kg。麻醉下经手术植入1 0 3 Pd放射性金属支架于犬的胆管腔内 ,1 0 3 Pd的放射性活度分别为 1 2 5× 1 0 4kBq、1 6 6× 1 0 4kBq、2 2 2× 1 0 4kBq、2 5 9× 1 0 4kBq、2 9 6× 1 0 4kBq和 3 7× 1 0 5kBq ,植入后 30d取出1 0 3 Pd放射性金属支架和胆管 ,后者经组织切片HE染色 ,光镜下进行放射性损伤的评价。结果　放射性活度为 1 2 5× 1 0 4kBq ,光镜下可观察到黏膜损伤 ;放射性活度为 2 2 2× 1 0 4kBq时胆管放射性损伤达肌层 ;放射性活度为3 7× 1 0 5kBq时放射性损伤达胆管壁外膜 ,出现胆管穿孔。根据不同放射性活度照射后 ,胆管的放射性损伤的放射性活度效应曲线得出 ,ED50 为 2 8 2× 1 0 4kBq。结论　1 0 3 Pd金属支架胆管腔内近距离照射有明显的剂量 效应关系 ,为该放射性支架应用于临床治疗胆管良、恶性狭窄提供重要的实验依据

Radiation injury of canine bile duct induced by 103Pd metal stent

Objective To assess radiation injury of dog bile duct induced by ¹⁰³Pd metal stent. Methods Hybrid dogs with body weight form 15 to 20 kg were used. ¹⁰³Pd metal stent was implanted into the common bile duct under anaesthesia, and the irradiation doses by ¹⁰³Pd were 12.5×10⁴kBq, 16.6×10⁴kBq, 22.2×10⁴kBq, 25. 9×10⁴kBq, 29.6×10⁴kBq and 3.7×10⁵kBq, respectively. Results Radiation injury on the mucosa of the bili duct was observed in 12.5×10⁴kBq group, and the damage extended to the muscular layer in 22.2×10⁴kBq group.Perforation of the bile duct was observed in 3.7×10⁵kBq group.The dose-response curve of radiation injury at different doses of intra-biliary metal stent ¹⁰³Pd showed the effective dose (ED₅₀) to be 28.2×10⁴kBq. Conclusion There is an obvious dose response relationship for in the ¹⁰³Pd metal stent.our result is unimportant theoretical basis for application of ¹⁰³Pd metal stent to clinical treatment of biliary cancer.