Bilateral Cochlear Otosclerosis; Clinic and Radiologic Findings

Otosclerosis is a focal osseous dyscrasia of the temporal bone in human. It can be categorized into 2 types: Fenestral and retrofenestral/cochlear, depending on the topography of the lesions. According to the involvement of disease different symptoms might be seen such as conductive, sensorineural, or mixt type hearing loss. Altough the certain diagnosis of disease is histopathologic investigation, high resolution computed tomography (HRCT) is the gold standard imaging modality in the diagnosis of otosclerosis. In this case, Forty-one years old female patient who suffers from unilateral mixt type hearing loss in her right ear was presented. Although there was only traffic accident in the past there was no evidence of ossicle dislocation and any disease that might cause conductive hearing loss on HRCT imaging. Bilateral cochlear otosclerosis was observed on HRCT. Her right ear was thought to be affected by cochlear otosclerosis expanded to the lateral wall of the otic capsule that had been caused a mixt type hearing loss in the right and a sensorineural hearing loss in the left. We revealed incidentally fenestral and cochlear type represented in continium in her right ear.It is important to perform radiologic investigation to clarify the concomitant pathologies in hearing loss.