Objective perilymphatic fistula assessment by cochlin-tomoprotein testing and tympanoscopy for round and oval window coverage as first line therapy in severe sudden sensorineural hearing loss

Introduction Treatment options of sudden sensorineural hearing loss (SSNHL) varies and is highly discussed. Application of corticosteroids as first line therapy are common although it is still not known to what degree this outruns spontaneous recovery. Although etiology of SSNHL is mostly idiopathic, hearing loss can result from perilymphatic fistula (PLF) due to membrane rupture of round and/or oval window. Recent findings show evidence of a rate of 47% of PLF based on cochlin-tomoprotein (CTP) detection test. Based on this high rate of PLF SSNHL treatment concepts need to be re-evaluated. The aim of this study was to detect CTP in SSNHL patients and compare pre-surgical and post-surgical pure tone hearing thresholds after round and oval window sealing as first line treatment.

Methods 38 patients with unilateral SSNHL were enrolled in a prospective study. After intraoperative observation of possible PLF all patients obtained middle ear lavage to gain CTP samples for following ELISA-based CTP detection tests. All patients received round window and oval window sealing with fascia. PTA hearing thresholds were analysed post-surgical 3 weeks after treatment based on 4-frequency bone conduction (BC). Recovery was defined as a mean BC of at least 10 dB.

Results The average preoperative pure-tone BC threshold was 91 dB compared with 69 dB postoperative BC threshold. Improvement of mean BC was 23 dB after middle ear exploration and window sealing. 63% (24 of 38) of patients recovered of at least 10 dB. Cochlin-tomoprotein positive rate was comparable to results in previous studies.

Conclusion Combination of tympanoscopy and CTP as detection tool for PLF offers new insights in pathophysiology and is a strong argument for a SSNHL 1st line treatment.

Publication History

Article published online:
19 April 2024