Autogenous inside-out versus standard vein and skeletal muscle-combined grafting for facial nerve repair

摘要

BACKGROUND:In the repair of nerve defects,collapse of the venous wall,as a result of vein grafting alone,could impede nerve regeneration.Therefore,vein lumens filled with muscle and nerve segments have been used to bridge nerve defects.OBJECTIVE:To compare the effects of autogenous,inside-out,vein-skeletal,muscle-combined grafting versus standard,vein-skeletal,muscle-combined grafting for the repair of facial nerve defects.DESIGN,TIME AND SETTING:A randomized,controlled,neuroanatomical,animal study was performed at the Animal Experimental Center and Laboratories of the Capital Medical University Xuanwu Hospital and the Peking Union Medical College Hospital from September 2007 to October 2008.MATERIALS:A total of 10 healthy,male,New Zealand rabbits,aged 6 months,were randomly assigned to inside-out,vein-skeletal,muscle-combined grafting and standard,vein-skeletal,muscle-combined grafting groups,with 5 rabbits in each group.METHODS:A 20-mm gap in the buccal branch of the right facial nerve was made in each animal,which was respectively repaired with inside-out,vein-skeletal,muscle-combined grafts or standard vein-skeletal muscle-combined grafts.MAIN OUTCOME MEASURES:At 6 months after implantation,evoked maximal compound muscle action potentials were recorded on bilateral facial nerves using electromyogram.Myelinated nerve fibers of the regenerating nerves were quantified using myelin sheath osmic acid staining.RESULTS:There was no significant difference between the groups in terms of ratios of bilateral amplitude and latency of compound muscle action potential(P>0.05).Moreover,morphology of regenerating nerves and quantity of myelinated nerve fibers were similar between the groups(P> 0.05).CONCLUTION:Compared with standard vein grafting,the inside-out vein grafting did not significantly improve nerve regeneration.Therefore,it is not necessary to utilize inside-out vein grafting for the repair of nerve defects,in particular with the combined use of autogenous vein and skeletal muscle grafts.