[Effects of round window membrane rupture on cochlear blood flow and endocochlear potential]

Occurence of a round window membrane rupture in patients with sudden sensorineural hearing loss

Background

Aim of the present study was to evaluate the occurence of a round window membrane rupture and the effects of hearing restoration after exploratory tympanotomy and sealing of the round window (niche) in patients with unilateral sudden deafness.

Methods

Retrospective analysis of patients’ charts in a tertiary referral center. Charts of 69 patients with sudden deafness followed by exploratory tympanotomy were retrospectively analyzed. Pure-tone audiometry data before and after tympanotomy were compared to determine the outcome of hearing recovery. The postoperative hearing test values were documented 3 weeks after tympanotomy. All surgical reports were reviewed with regard to the surgical technique performed and the intraoperative findings.

Results

18.8% of the patients revealed a visible perilymphatic fistula in the round window niche. 89.8% of the patients reported no typical history for a round window membrane rupture. All patients were treated with an exploratory tympanotomy under local anesthesia and an intravenous corticosteroid treatment regimen. The majority of the surgeons used a fat plomb to cover the round window. Postoperative hearing was significantly improved compared to the preoperative hearing test data. No patient showed a worsened hearing curve after the treatment.

Conclusion

Most patients suffering from unilateral sudden deafness had no visible perilymphatic fistula. In our study population, the majority of patients reported no typical history of a pressure elevation in the inner ear. Exploratory tympanotomy is a safe procedure that may support hearing recovery in patients with sudden deafness in addition to the established treatment regimen including high-dose steroids.