Laryngeal Reinnervation For Vocal Cord Paralysis

PART 1Delayed laryngeal Restoration:AComparison of Nerve Suturewith Neuromuscular Pedicle Transfer and Nerve Implantation Objective: To determine which method was the best for reinnervating the laryngeal adductormuscles by comparing nerve suture, nerve implantation, and nerve muscular pedicle transfer, as wellas the lengthy of time that could elapse after denervation and still allow for successful reinnervationwith the ansa cervicalis. Methods: Forty one dogs were divided into four groups to undergo nervesuture, nerve implantation, neuromuscular pedicle transfer or control experiments respectively.Three groups were reinnervated at the time of denervation and six-, eight-, ten-, twelve- andeighteen-month following denervation via nerve suture, nerve implantation or neuromuscular pedicletransfer for restoration of the vocal cord adductors. Results: Some recovery of adduction was notedin the cases for nerve suture within ten-month interval and for nerve implantation or neuromuscularpedicle within eight-month interval transfer. Laryngeal electromyography, tension measurement andhistochemical studies of the adductor muscles were correlated with the recovery of adduction.Although adduction didn't recover after the intervals, the bulk and strength of the adductor muscleswere still regained partially. Nerve suture was superior to nerve implantation and nerve musclepedicle technique in the three procedures of reinnervation. Little difference was noted in thefunctional recovery, electrophysiological activity and muscle strength between nerve implantation andnerve muscle pedicle transfer. Conclusions: Nerve suture was superior to nerve implantation andnerve muscle pedicle technique. Variable return of adduction could be achieved in the cases operatedbefore a 10-month interval for reinnervation with nerve suture and an 8-month interval with nerveimplatation and nerve muscle pedicle transfer.