Trigeminal neo-neurotization of the paralyzed face.

Sporadic reports throughout the literature have documented the spontaneous return of facial function following deliberate intraoperative sacrifice of the facial nerve. Trigeminal reinnervation of the facial muscles has been suggested as one possible mechanism for this occurrence. Evidence for the phenomenon of trigeminal neo-neurotization has been documented experimentally. The case of a 62-year-old woman who underwent total left parotidectomy with transection of a large facial nerve segment is presented in order to provide further clinical evidence supporting trigeminal neo-neurotization of the facial nerve. Despite the lack of any efforts to reinnervate the patient or graft the facial nerve defect, the patient spontaneously developed return of facial function. Postoperative clinical and electrical testing in this case supports trigeminal-facial reinnervation as the cause for return of facial function. The case report is summarized with a brief discussion, and the relevant literature is thoroughly reviewed.