[Sudden deafness caused by rupture of the round window membrane. Surgical indications, course and prognosis].

Tympanotomy was performed on 39 of 247 patients with sudden hearing loss between 1980 and 1982. In 23 cases a round window membrane defect was found. Evaluation of the indications, intraoperative findings and postoperative course allows the following conclusions to be drawn. Only in patients treated in the second week was the rate of success significantly higher than the spontaneous remission rate in patients without perilymphatic fistula. If there is no improvement in the hearing level in the first week after covering a round window membrane defect the prognosis is poor. Stabilization of the hearing is complete in the first three weeks after treatment. Prognosis in extensive membrane defects with large perilymphatic fistulas is definitely worse than in small round window membrane defects. The best results were achieved for the following groups: physical exertion/barotrauma, sudden deafness, progressive hearing loss despite drug therapy.