生物型神经导管桥接兔面神经缺损

Effects of biotype nerve conduit on bridging rabbit facial nerve defects

目的:评价生物型神经导管在桥接兔面神经缺损中的作用.方法:选择健康成年新西兰大白兔48只,随机分为A,B两组,A组为自体腓神经移植组,B组为神经导管组,各组24只,每组内设3小组,每小组8只.术后观察动物面部胡须及肌肉运动情况并进行评分,第4,8,16周时行神经电生理检查,后处死动物取标本行组织HE及神经纤维染色.结果:术后早期各组动物患侧面瘫表现,上唇运动明显减弱,患侧胡须由水平垂向后下方,2 wk左右患侧面部轻度萎缩,但自8wk后A组及B组动物上唇及胡须运动部分有改善,至16 wk时两组动物患侧的上唇胡须运动幅度、节律及肌萎缩现象基本恢复.两组面部胡须运动功能评分在第10,12,14周有统计学差异(P<0.05).大体解剖发现B组术后8 wk神经导管部分吸收,与周围粘连不明显,术后16 wk神经导管大部分吸收,可见新生神经纤维.术后电生理检测结果显示16 wk时两组神经传导速度比较有统计学差异(P<0.05),A,B组随时间延长神经传导速度及有髓神经纤维数目均逐渐增加,且两组变化趋势不同,A组增长趋势较快.HE染色及神经纤维染色显示随着时间的推移,B组再生神经纤维逐渐趋于成熟,结果稍逊于A组.有髓神经纤维计数结果显示各组随着时间的推移神经纤维数目逐步增加,在8,16 wk时A组神经纤维数目高于B组,均有统计学差异(P<0.05).结论:生物型神经导管对面神经短距离缺损能起到一定的修复作用,有可能引导和促进神经再生.

AIM： To evaluate the effect of biotype nerve conduit on bridging rabbit facial nerve defects. METHODS： Forty-eight healthy adult New-Zealand rabbits were divided into 2 groups： Auto-personal nerve group （ A ） and nerve conduit group （ B ）. Each group was then subdivided into 3 groups, with 8 rabbits in each one. After operation, rabbits＇ behaviors including whiskers movement and lips sucking were observed. Nerve electrophysiological examination and histology study were performed on 4th, 8th and 16th week postoperatively. RESULTS ： After operation, facial paralysis was observed in the injured side of rabbits in each group and slight atrophy was seen at 2nd week. At 8th week, whiskers movement and lips sucking improved in both group A and group B, and at 16th week, whiskers movement and lips sucking almost recovered in both groups. The score of whiskers motor function in group A was higher than that in group B and the difference was statistically significant at 10th, 12th and 14th week （P 〈 0.05 ）. At 8th week, gross anatomy showed that nerve conduit in group B was partly absorbed with a little conglutination, but at 16th week most of it was absorbed and new nerve fibers appeared. Significant difference was found in the mean nerve conduction velocity between group B and group A at 16th week （ P 〈 0.05 ）. The histology study showed that the rabbit facial nerve regenerated with the passage of time. The regenerated nerve in group B was gradually mature, but not as good as that in group A. The number of myelinated fibers in group A and group B increased gradually as time went on, but the number in group A was higher than that in group B at 8th and 16th week（ P 〈0. 05）. CONCLUSION： The biotype nerve conduit may effectively repair rabbit facial nerve defect in a short distance, which may guide and promote nerve regeneration.