Facial nerve morbidity after retrograde nerve dissection in parotid surgery for benign disease: a 10-year prospective observational study of 136 cases.

We evaluated the facial nerve function in 136 patients who had had retrograde nerve dissection during parotidectomy for benign disease. One week after the operation 90 patients (66%) had some weakness of the facial nerve. After 1 month 52 (38%) had facial nerve paresis. After 3 months 114 (84%) had recovered fully and 21 (16%) had minor nerve paresis. After 6 months 135 (99%) had normal nerve function. One patient had persistent marginal mandibular nerve paresis.