Functional Recovery After Facial Nerve Cable Grafting in a Rodent Model

IMPORTANCE Cable grafting is widely considered to be the preferred alternative to primary repair of the injured facial nerve; however, quantitative comparison of the 2 techniques has not been previously undertaken in a rodent model. OBJECTIVE To establish functional recovery parameters after interposition autografting in a rodent facial nerve model. DESIGN, SETTING, AND PARTICIPANTS Prospective randomized animal study at a tertiary care facial nerve center using 16 female Wistar Hannover rats. INTERVENTION The experimental group received reversed autograft reconstruction of a 20-mm neural gap, and the control group received facial nerve transection and primary repair. MAIN OUTCOME AND MEASURE Whisker excursion was measured weekly for 70 postoperative days using laser micrometers. RESULTS The control group exhibited the most rapid recovery, with substantial return of whisker movement occurring during the third postoperative week. The experimental group demonstrated return of function beginning in the fourth postoperative week, eventually achieving a degree of function comparable to that of the control group by the sixth postoperative week (P = .68). CONCLUSIONS AND RELEVANCE Recovery of facial function after cable grafting seems to be slower than, but eventually similar to, recovery after primary neurorrhaphy in a rodent model. In the present study we have established a benchmark for recovery of whisker movement across a 20-mm rodent facial nerve gap, which will be used for comparison of different facial nerve gap bridging materials in future studies.