Introduction:
Surgical treatment of otosclerosis requires considerable experience of the otosurgeon, especially in advanced cases or in an ear with an unusually narrow external auditory canal, a narrow niche of the round window, a significantly thickened stapes footplate, or an exposed or hanging facial nerve. Case involving subsequent reoperations by different surgeons can be particularly difficult. Collective knowledge of treatment failures during otosclerosis reoperation, as set out in the literature, does not list the difficulties encountered, fails to assess most causes of failure, and does not describe remedies and corrective techniques.

Material and Methods:
The course of treatment followed by a 55-year-old complaining of progressive, bilateral, mixed hearing loss due to otosclerosis is described. The patient’s treatment consisted of stapes mobilization, followed by stapedotomy and restapedotomy of the right ear, and stapetodomy of the left ear.

Results:
There was short-term improvement of hearing after mobilization of the stapes, but its subsequent deterioration, with elevation of both the air- and bone-conduction thresholds in the right ear, were indications for reoperation and stapedotomy. Short-term improvement in hearing was achieved after the operation, followed by rapid hearing loss. Due to this and growing balance disorders after nearly a year, a restapedotomy was performed with complete closure of the air-bone gap. Then, due to hearing deterioration in the left ear, a successful stapedotomy was performed in this ear.

Conclusions:
Revision operations in otosclerosis require a lot of experience of the otosurgeon due to the many reasons for failure, particularly when the first surgery was performed elsewhere. An air-bone gap, severe tinnitus, and balance disorders are indications for reoperation by an experienced otosurgeon, as common causes of failure are postoperative adhesions and subsequent stapes immobilization.