The Experimental Study Of Double-Bridging Of Facial Nerve Defect In Rabbits By Chitolsan-Collagen Chambers

Objective To evaluate the feasibility and the superiority of repairing the longer defects in rabbits by double-bridging technique and chitosan-collagen chambers, and to find a new simple, effective method for treatment of long nerve defect which would be widely used by grass-roots surgeons. Methods 15mm defects in right facial nerve of rabbits were repaired dividly in four groups: double-bridging with little gap, double-bridging without gap, nerve autografts, and normal control. General observation, electrophysiological study, histological study and image analysis were performed 12 weeks postoperatively . All results were used to evaluate the nerve regeneration. Results (1)chitosan-collagen chambers were obviously degraded 12 weeks postoperatively and there was no foreign bodyreaction at this stage. They also restrain the formation of neuroma and provided a good microcircumambience for nerve regeneration . (2) The recovery of nerve regeneration was good in double-bridging groups. There was no significant difference between the double-bridging groups and nerve autografts, but they all did not recover to normal level. (3) There was no significant difference between double-bridging groups and nerve autografts group in the rate of regeneration of myelinated axoh. The double-bridging groups were a little lower than the nerve autografts group in the recovery rate and the maturity degree of myelinated axon. Conclusion (1) double-bridging technique is a simply method for treatment of long nerve defect and its effect is certain . (2)chitosan-collage chambers is suited to implant into body in order to repair of a nerve defect with excellent biocompatibility . (3)There was no significant difference between the double-bridging with little gap group and double-bridging without gap group. They all promoted the nerve regeneration.