Presentation
Bilateral conductive hearing loss.
Patient Data
Age: 15 years
Gender: Male
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Axial CT of the temporal bones at the level of the oval window demonstrates bilateral focal hypodensity at the fissula ante fenestram. There is bilateral near-symmetrical peri-cochlear hypodensity surrounding the cochlear turns, determining the double ring sign.
Findings are typical of bilateral fenestral and retrofenestral otosclerosis.
Case Discussion
Otosclerosis is a primary osteodystrophy of the otic capsule and classically is divided into two types: fenestral and retrofenestral.