Osteoma of the internal auditory canal.

Osteomas of the internal auditory canal, inaccesible to clinical examination, are rare lesions. There are only 14 cases of osteomas and exostoses of the internal auditory canal reported in the international medical literature. A patient with an osteoma of the internal auditory canal is presented, along with differential diagnosis and possible etiologic factors for the lesion. The auditory brainsteam evoked response testing showed increased absolute latencies of 1 wave and discrepancy of the wave morphology due to bony compression of the eight nerve in the internal auditory canal. Computed tomography showed a bony growth in the internal auditory canal. Magnetic response showed no abnormalities. No surgery was performed since the symptoms improved by conservative therapy.