Simultaneous Repair of Isolated Bilateral Congenital External Auditory Canal Atresia: Case Report and Review of the Literature

Abstract

Congenital external auditory canal(EAC) atresia describes the condition of an embryologically malformed external auditory canal. The widely accepted incidence of aural atresia is one in 10,000 to 20,000 live births. The incidence of bilateral atresia is roughly five times less than unilateral atresia. EAC is closed with ectodermal plug in a 30 mm embryo. This plug re-canalizes after the 21st week. The problems in embryopathogenesis during this period cause isolated EAC stenosis. A 37-year-old female was admitted with bilateral hearing loss since her childhood. On examination of the case with no other complaint, the EACs were short and closed conically. There was a conductive type of hearing loss at 50 dB in the right ear (air bone gap 40 dB), and at 47 dB (air bone gap 37dB) in the left ear on the pure tone audiogram. On temporal bone CT, bilateral the EACs were observed to be obstructed with fibrous-osseous tissue density at the tympanic membrane level. Depending on the radiological findings, it received 9 points according to the Jahrsdoefer classification. Bilateral ear was operated simultaneously and the skinless part of the ear canal was grafted with the use of a split thickness skin graft. The case was followed-up one year. Otoscopic examination at the end of the first year was normal and air conduction threshold was 15 dB (air bone gap 7 dB) on the right, and 8 dB (no gap) on the left.