Surgery for necrotizing otitis externa-indications and surgical findings

Treatment for necrotizing otitis externa (NOE) includes long term antibiotic and surgery in selected cases. Indications and extent of surgery, however, are still not defined. The aims of this study were: (1) present our experience in surgery for NOE (2) compare high-resolution computer tomography and perioperative findings (3) suggest recommendations for indications and extent of surgery.

A retrospective case series study was conducted in a tertiary referral center. Patients hospitalized due to NOE between the years 1990-2015 and underwent surgery were included.

Twenty patients were included in the study. HRTBCT was performed in 17 patients. Most common radiological findings included mastoid fullness (n = 13, 76.4%) and edema of external ear canal (n = 12, 70.5%). Surgical indications included lack of response to treatment (n = 18) and facial nerve palsy (n = 2). Seven patients underwent local debridement. Most common operative findings included soft tissue necrosis (n = 4, 57.1%) and gross bony destruction of the external ear canal (n = 2, 28.5%). Thirteen patients underwent tympanomastoid surgery. Most common operative findings included granulation tissue in the mastoid (n = 7, 53.8%) and mastoid bony erosion (n = 4, 30.7%). Facial canal involvement was seen in four patients (30.7%).

This is the first study to describe a large group of surgically treated NOE. Initial surgical approach should be based on clinical and HRTBCT findings. Minimal HRTBCT findings may be addressed with local debridement. Severe HRTBCT findings should be addressed with canal wall up mastoidectomy as the minimal surgical procedure. Further extent should be decided based on perioperative findings.