兔面神经延长的实验研究

目的 :研究扩张延长周围面神经的水囊合理注水量与延长值。方法 :使用组织扩张器对3组 (每组 1 0只 )兔面神经行一次性扩张延长 ,水囊注水量分别为 4、6和 8ml,注水后保持 5 min。注水前后分别进行肌电测定 ;并在光镜、透射电镜下进行组织学观察。结果 :3组延长值分别为9.2 2 %、1 5 .0 0 %和 2 2 .1 0 %。前两组的神经传导速度 ,神经扩张前后相比无明显差别 ,第 3组则比延长前明显减慢。前两组轴突密度扩张部与正常神经相比无明显差别 ,第 3组密度明显降低。前两组神经形态学及超微结构正常 ,髓鞘为圆形 ,排列规则 ,第 3组束膜间有血管扩张、间质水肿、出血及脱髓鞘变化。结论 :兔面神经一次扩张延长的水囊合理注水量为 6ml,延长值为 1 5 .0 0 %。

Experimental Study on Lengthening of Facial Nerve in Rabbits

Objective: To investigate the infusion volume and relevant lengthening value of expansion for peripheral facial nerve. Methods: Tissue expander was applied in three groups of rabbits (10 rabbits in each group) to lengthen the facial nerve in one step by infusion of 4, 6 and 8 ml water respectively. Electromyographic testing was carried out before infusion and 5 min after infusion. Histological examination under light microscope and electron microscope were also done. Results: The lengthening value was 9.22%, 15.00% and 22.10% in three group, respectively. There was no significant difference of motor nerve conduction velocity before and after nerve expansion in the first 2 groups. In the third group, however, motor nerve conduction velocity was slower after nerve expansion. In the first 2 groups, the axon density, the structure and ultrastructure of the lengthened nerve were almost normal, while decreased axon density, interfascicular vessel dilation, interstitial edema and hemorrhage, demyelination, and shrinkage of myelin sheath were observed in the nerve of the third group. Conclusion: The optimal infusion volume for one stage rabbit facial nerve expansion was 6 ml and the nerve lengthening value was 15.00%.