Otosclerosis involving oval window, obliterative

This code describes otosclerosis, a condition characterized by abnormal bone growth in the middle ear, specifically affecting the oval window. In this obliterative form, the stapes footplate becomes completely fixed in the oval window, severely impairing sound conduction and leading to progressive conductive hearing loss.

Use this code when documentation explicitly states otosclerosis with involvement of the oval window, and further specifies an "obliterative" nature. This typically occurs in cases of advanced otosclerosis where the stapes is completely immobilized. Supporting documentation would include audiometry showing significant conductive hearing loss, otoscopic findings, and surgical reports detailing the extent of stapes fixation.

• Differentiate from non-obliterative oval window involvement, which would be coded differently.
• Ensure the documentation clearly specifies "obliterative" to support this specific code.
• Consider sequencing this code as the primary diagnosis when it is the reason for the patient's visit and treatment.