Experience with the SOUNDTEC Implantable Hearing Aid

Abstract

OBJECTIVE: To assess the efficacy, morbidity, and patient satisfaction of the SOUNDTEC semi-implantable hearing aid. STUDY DESIGN: Retrospective case review. SETTING: Two tertiary referral centers (the Silverstein Institute and the Atkins Institute). PATIENTS: Sixty-four (four bilateral placements) patients with bilateral moderately severe sensorineural hearing loss: 47 patients had previously worn hearing aids. INTERVENTIONS: After separating the incudostapedial joint, a magnet encased in a titanium canister with a ring was introduced onto the stapes neck. Gelfoam or adipose tissue was used to stabilize the magnet. After 3 months, the external processor was fitted. MAIN OUTCOME MEASURES: At 1 month, audiometric testing was performed and functional gain was assessed. Patient acceptance and implant performance were measured by a visual analogue questionnaire. RESULTS: The device produced an average functional gain of 26 dB. Fifty-five percent of patients complained of magnet movement; this was eliminated in 80% of Silverstein Institute patients when the external processor was worn and fat was used to stabilize the magnet. CONCLUSION: The SOUNDTEC direct device is well tolerated in the majority of patients, with a significant increase in functional gain. Magnet instability and noise were the most frequent complaints and improved with processor placement and anchoring the magnet with fat. This electromagnetic semi-implantable hearing aid confers greater functional gain over conventional hearing aids and reduces occlusion effect and feedback.