Surgical management of iatrogenic facial nerve injuries

Surgical management of an iatrogenic facial nerve injury represents a significant challenge for the otologic surgeon. The decision to perform facial nerve grafting is a difficult one and is based on the extent of injury to the nerve. We conducted a review of 22 patients who had sustained iatrogenic facial nerve injuries during otologic surgery that required surgical exploration. The facial nerve was transected more than half its diameter in 13 of the patients. All of these patients' nerves were repaired either with direct reanastomosis of the facial nerve or with a cable nerve graft. The transection was less than 50% in nine of the patients in the study group. Eight of these patients underwent only decompression of the facial nerve. No patient with a neural repair (direct anastomosis or cable graft) had better than a House grade III result. All of the patients undergoing direct anastomosis of the nerve obtained a House grade III result. The most common result in patients undergoing cable nerve grafting was a House grade IV. The only patients with normal or near-normal facial nerve function (House grade I or II) had only decompression of the facial nerve. Five of the eight patients undergoing decompression had results similar to those undergoing cable nerve grafts. We conclude that acceptable results can be obtained when the facial nerve is repaired by direct anastomosis or a cable nerve graft. These results are comparable with those of patients treated with decompression only. When in doubt as to the extent of injury, it is preferable to repair the facial nerve, because the extent of injury may be underestimated.