Otosclerosis involving oval window, nonobliterative

This code describes otosclerosis, a condition characterized by abnormal bone growth in the middle ear, specifically affecting the oval window. In this nonobliterative form, the stapes footplate is fixated but not completely overgrown or fused, leading to conductive hearing loss.

Use this code when documentation clearly indicates otosclerosis affecting the oval window, and the surgeon or audiologist specifies that the stapes footplate fixation is not completely obliterative. This diagnosis is typically supported by audiometric findings of conductive hearing loss, a positive Rinne test, and often a family history of otosclerosis.

• Differentiate from obliterative otosclerosis, where the oval window is completely overgrown.
• Ensure documentation specifies "nonobliterative" or similar language indicating partial fixation.
• Consider laterality if specified in the documentation (e.g., right, left, bilateral).