犬同种异体颜面复合组织移植模型的建立及面神经再生的初步研究

The Mode Building of Dog Facial Composite Tissue Allograft and the Preliminary Study of Facial Nerve Regeneration

目的建立犬同种异体颜面复合组织移植的动物模型,观察移植后面神经的再生情况。方法 (1)模型建立:取杂种犬3只进行头颈部(主要是血管系统和面神经颅外段)的解剖研究。明确血管蒂所能营养组织块的最大范围,寻求最合适的血管蒂进行复合组织瓣移植。(2)移植后面神经再生的观察:以2只Beagle犬分别作为供/受体,建立实验动物模型后,环孢素A与皮质激素联合应用作为免疫抑制治疗方案。术后60,100 d分别行面神经肌电图检测,术后100 d取移植面神经吻合口标本行病理观察,分析移植后面神经的再生情况。结果 (1)犬头颈部血管和面神经颅外段的分支及走向与人类似,面神经颊支粗大且走向恒定,可作为移植神经。进行犬半侧颜面组织瓣移植最合适的血管蒂应是颈外静脉和颈外动脉。(2)移植术后60 d神经肌电图检测指标潜伏期较正常明显延长,波幅明显减小,100 d时潜伏期与波幅均较前明显恢复改善。神经吻合口的组织学结构接近正常。结论建立包含面神经的犬同种异体颜面复合组织移植动物模型具有可行性,可作为长期观察的动物模型。移植后面神经的再生是个较为缓慢的过程,移植100 d神经吻合口远端可出现组织结构上较为成熟的再生神经纤维,但要达到功能上的恢复尚需更长的时间。

Objective To establish an animal model of facial composite tissue allograft transplantation and do a preliminary study on facial nerve regeneration.Methods（1）Mode building： take 3 hybrid dogs to do the head and neck anatomy（mainly on vascular system and extra-cranial segment of facial nerves）,and clarify the maximum extent of tissue block supply of each vessel pedicle,and find the most proper and reliable vessel pedicle,which could be used to do the transplant of composite flap.（2）Observation of nerve regeneration after transplantation： Take 2 Beagle dogs as donor and acceptor to build an experimental model of facial composite tissue allograft transplantation.Cyclosporine A is combined with corticosteroids as immunosuppressive treatment.A facial nerve test will be taken by electro-radiogram after operation both in 60 days and 100 days.Take facial nerve anatomist＇s specimens of transplantation after 100 days＇ operation to do the H-E stain light microscopy and transmission electron microscopy observation to analyze the facial nerve regeneration condition.Results（1）The blood vessels branch of dog neck and facial nerves are similar to the human.The buccal branches of facial nerve are coarse and constant that can be used as transplant nerve.The best suitable vessel pedicle used to do hemifacial tissue transplantation is external jugular vein and carotid artery.（2）Latency of EMG detection index was significantly longer than normal,and the amplitude was significantly reduced after 60 days＇ transplantation.The amplitude and latency was getting improved after 100 days.The nerve anastomosis was almost normal in histological structure after 100 days.Conclusion The Beagle dog model established in the experiment included facial composite tissue allograft transplantation is feasible and can be used as a long term observation model.The regeneration of facial nerve transplantation is slow and has to go through a series of pathological and physiological processes.More mature regeneration nerve fibers will occur on nerve anastomosis after 100 days＇ transplantation and it takes more time to reach functional recovery.