Internal auditory canal exostosis: A technical case report

BACKGROUND: Exostoses of the internal auditory canal is a rare finding that may present with disabling symptoms of dizziness, hearing loss, and vestibular dysfunction based on the extent of cranial nerve compression. The purpose of this case report is to discuss the presentation and outcomes in a patient who presented with this disorder. CASE DESCRIPTION: A 19-year-old female presented to the neurotologist with left ear discomfort, pain with left lateral gaze, and dizziness. She underwent extensive evaluation including audiometric testing, videonystagmography, and neuroimaging, which confirmed left auditory and vestibular hypofunction and compression of the contents of the internal auditory canal from the exostosis. After extensive counseling, the patient elected to undergo a suboccipital craniectomy to remove the internal auditory canal exostosis. She experienced complete resolution of symptoms. CONCLUSIONS: Exostoses of the internal auditory canal, although rare, can present with severe symptoms of dizziness, hearing loss, and vestibular hypofunction based on the extent of cranial nerve compression. Imaging, particularly with thin-cut computed tomography, is invaluable in making the correct diagnosis. Severe cases can be treated successfully with surgery with minimal or no complications and excellent outcome.