Isolated congenital internal auditory canal atresia with normal facial nerve function

Area of Science:

• Otolaryngology
• Developmental Biology
• Neuroscience

Background:

• The internal auditory canal (IAC) forms from mesoderm surrounding the eighth cranial nerve during embryonic development.
• Atresia or stenosis of the IAC is theorized to stem from abnormal cochleovestibular nerve development.
• IAC anomalies often accompany other inner, middle, or external ear abnormalities, or systemic developmental issues.

Observation:

• This report presents a rare case of bilateral, congenital internal auditory canal atresia.
• The patient exhibited significant cochleovestibular deficits.
• Notably, facial nerve function was preserved in this individual.

Findings:

• The case highlights a rare instance of isolated bilateral IAC atresia.
• It underscores the potential for severe cochleovestibular impairment with intact facial nerve function.
• Literature review indicates such anomalies are infrequently isolated and often associated with systemic developmental issues.

Implications:

• This case expands the understanding of IAC atresia presentations.
• It emphasizes the need for comprehensive audiological and neurological assessment in affected individuals.
• Further research into the embryological mechanisms and management of IAC atresia is warranted for improved patient outcomes.