Axonal regeneration rate through cross-face nerve grafts.

The disfigurement of irreversible unilateral facial paralysis can be corrected by cross-face nerve grafting in conjunction with muscle transplantation. A total of 33 patients underwent cross-face nerve grafting using the sural nerve prior to undergoing the second stage of the procedure. Before a muscle transplant can be successfully connected to the distal end of the cross-face nerve graft, the regenerating axons need to have grown from the contralateral facial nerve to the distal end of the nerve graft. This can be tested by the Tinel sign. A retrospective study was performed to determine the rate of growth of regenerating axons through the cross-face nerve graft. A rate of axon growth of 1.8 mm/day was found, and also an inverse relationship between the age of the patient and the regeneration rate. These results can be used as a guide in planning patients' treatment.