[Otosclerosis: study of the postoperative course of hearing during the first 5 years and research of some prognostic factors. Apropos of a series of 67 cases].

Post-operative air conduction and bone conduction thresholds at 3 months, 1 year and 5 years after stapedectomy or stapedotomy in 67 patients were studied. Bone conduction thresholds improved in the first year postoperatively, then decreased progressively, less than in the non-operated ear but more than in a normal population. The air-bone gap was closed in 75% of the patients. The air-bone gap stayed at the same level during the studied period. Air conduction and bone conduction thresholds are better in the stapedotomy group than in the stapedectomy group only in the 4000 Hz frequency, and are similar for both groups in the 500-2000 Hz range.