High-resolution CT findings of otosclerosis

Objective To evaluate HRCT features of otosclerosis.Methods HRCT findings of 61 ears with the diagnosis of otosclerosis based on clinical diagnostic criteria in 34 patients were evaluated retrospectively.Results Hypodense regions in the bony otic capsule were found on HRCT in 55 ears and no abnormality was identified on HRCT in 6 ears.In 55 ears with abnormal HRCT findings, HRCT demonstrated the hypodense region of bony otic capsule anterior to oval window alone in 6 ears, the hypodense region anterior to oval window associated with thicked stapedial footplate and pericochlear hypodensity in 6 ears, the hypodense region anterior to oval window associated with thicked stapedial footplate and hypodensity posterior to oval window in 11 ears, the hypodense region anterior to oval window associated with thicked stapedial footplate in 20 ears, the hypodense region anterior to oval window associated with pericochlear hypodensity in 10 ears, and pericochlear hypodensity in the bony otic capsule alone in 2 ears.Conclusion HRCT can detect abnormalities in the bony otic capsule and the stapedial footplate,contributing to confirming diagnosis of otosclerosis. Key words: Otosclerosis; Temporal bone; Tomography, X-ray computed