Iatrogenic facial nerve injuries during chronic otitis media surgery: a multicentre retrospective study.

OBJECTIVES: To give an insight into why, when and where iatrogenic facial nerve (FN) injuries may occur and to explain how to deal with them in an emergency setting. DESIGN AND SETTING: Multicentre retrospective study in eight tertiary referral hospitals over 17 years. PARTICIPANTS: Twenty patients with partial or total FN injury during surgery for chronic otitis media (COM) were revised. MAIN OUTCOME MEASURES: Indication and type of surgery, experience of the surgeon, intra- and postoperative findings, value of CT scanning, patient management and final FN outcome were recorded. RESULTS: In 12 cases, the nerve was completely transected, but the surgeon was unaware in 11 cases. A minority of cases occurred in academic teaching hospitals. Tympanic segment, second genu and proximal mastoid segments were the sites involved during injury. The FN was not deliberately identified in 18 patients at the time of injury, and nerve monitoring was only applied in one patient. Before revision surgery, CT scanning correctly identified the lesion site in 11 of 12 cases and depicted additional lesions such as damage to the lateral semicircular canal. A greater auricular nerve graft was interposed in 10 cases of total transection and in one partially lesioned nerve: seven of them resulted in an HB III functional outcome. In two of the transected nerves, rerouting and direct end-to-end anastomosis was applied. A simple FN decompression was used in four cases of superficially traumatised nerves. CONCLUSIONS: We suggest checklists for preoperative, intraoperative and postoperative management to prevent and treat iatrogenic FN injury during COM surgery.