(A954) Type I First Branchial Cleft Abnormality with Aural Atresia: Undetected External Auditory Canal

Introduction: We present a case of Type I FBCA associated with microtia and aural atresia that exhibited no canal presence on MRI but subsequent discovering of an external auditory canal on endoscopy.

Methods: This is a case report conducted in 2024-01/2025. The subject was a 5-year-old male who was initially diagnosed with a type I first branchial cleft abnormality with microtia and aural atresia and underwent a canaloplasty after discovering of an external auditory canal at Arkansas Children's Hospital. Creating a functional canal improved sound recognition on the affected side but due to hypoplastic ossicles and tympanic membrane, complete resolution of conductive hearing loss is not possible.

Results: Creating a functional canal improved sound recognition on the affected side but due to hypoplastic ossicles and tympanic membrane, complete resolution of conductive hearing loss is not possible. Postoperative audiometric testing showed a slight improvement in the conductive hearing loss along with a type B tympanogram in left ear. The patient’s conductive hearing loss is being successfully managed with a bone-conduction hearing aid attached to a flexible headband.

Conclusions: This patient was initially diagnosis with a type I first branchial cleft abnormality with microtia and aural atresia with no presence of external auditory canal on MRI but an additional endoscopic exploration led to the discovery of an EAC. This case is one of few documented FBCA with presence of a cartilaginous EAC adding to the vast presentations that FBCA can have.