Middle Ear Implant for Sensorineural and Conductive Hearing Loss: Indications and Audiological Results

Abstract

Background and Objectives Middle ear implants (MEI) have been reported to be an effective and safe alternative for the treatment of sensorineural hearing loss (SNHL) and conductive hearing loss (CHL). This study aimed to compare the functional outcomes between SNHL and CHL in terms of audiological gains. Subjects and Method The medical records of 14 consecutive SNHL and CHL patients who underwent MEI surgeries from 2015 to 2019 by a single surgeon were retrospectively reviewed. Audiological changes using hearing aids (HA) and MEI were compared. Results In SNHL, the mean unaided air-conduction pure tone audiometry (PTA), (57.7 dB HL) decreased significantly using HA and MEI (44.7 and 41.4 dB HL), but with no significant difference from each other. Unaided word recognition score (WRS) at 65 dB HL (45.1%) was significantly improved using HA and MEI (72.6% and 76.6%), with no significant difference. In CHL, the mean unaided air-conduction and bone-conduction PTA were 77.1 (57.5-93.8) and 44.1 (26.3-57.5) dB HL. Three patients could not use conventional HAs due to otorrhea and deformity of the external auditory canal by previous surgeries and 4 patients had used conventional HAs before MEI. Though both HA and vibrant soundbridge (VSB) showed improvement of hearing thresholds (32.0 and 48.8 dB HL) and WRS (80.0% and 94.9%), it was significant only when using VSB. There was no significant difference between HA and VSB. Conclusion MEI can be an effective treatment option for both SNHL and CHL patients, especially for those who suffered from problems using conventional HA.