(012) Acquired Ear Canal Atresia: Causes, Repair Techniques, and Outcomes

Introduction: Acquired external auditory canal (EAC) atresia is a rare pathology with possible etiologies including traumatic, inflammatory, post-surgical, and neoplastic. There is limited literature on surgical technique and outcomes, particularly pre- and post-op audiometric data.

Methods: This is a retrospective case series examining patients who underwent surgery for acquired EAC atresia at three hospitals in New Orleans, LA, from 2018-2023. Etiology, type of surgery, the thickness of the fibrotic plug, presence of cholesteatoma, the status of the tympanic membrane (TM), subjective improvement of hearing, and follow-up period were recorded. When available, change in the air and bone pure tone average (PTA) and word recognition score (WRS) pre- and post-op were examined.

Results: Thirteen patients (Male=8), with a mean age of 50yrs (17-75yrs), underwent surgery. The majority (n=7) developed atresia due to chronic otitis; others were related to trauma. The average thickness of the plug in the axial plane was 8mm (4-12.5mm) in ten patients. Cholesteatoma (actively desquamating epithelium trapped medial to the plug) was identified in six (46%) patients. The TM was damaged, perforated, or adhered to the fibrotic plug in seven (54%) patients, requiring a tympanoplasty. The EAC skin was reconstructed with a split-thickness skin graft (STSG) in ten (80%) patients. Donor sites included the auricle (n=6, 60%) and leg (n=4, 40%). Thus far, the follow-up period ranges from 1 week to 4 years. Every patient has reported improved hearing. Atresia has not recurred for any patient. Four patients had available pre- and post-op PTA data. There was an average improvement of 21dB, measured on average four months post-op. Three patients had available pre- and post-op WRS data. Two patients remained at 96% and 100%, and the other improved by 16% at seven months post-op.

Conclusions: Cholesteatoma medial to the atretic segment was identified in nearly half of the patients. Surgical repair is possible and requires skin grafting and/or tympanoplasty. Regardless of etiology or grafting technique, hearing improved and atresia did not recur.