Soundbridge-Implantation in patients with mixed or conductive hearing loss: influence of FMT coupling structure on postoperative speech recognition and effective hearing gain

Introduction Patients with conductive or mixed hearing loss after multiple tympanoplasty with poor ventilated middle ear and/or malformations are often unsatisfied with conventional hearing aids due to the high hearing threshold loss. From an audiological point of view, the Vibrant Soundbridge (VSB) is the ideal solution for patients with a low to moderate inner ear component.

Patients and methods Between 2010 and 2020, 81 patients were treated with a VSB and were followed up in the internal audiology department for at least 6 months. Depending on the pathology, the FMT was coupled to the incus (n = 17), the stapes head (n = 22) or the round window (n = 42). Speech recognition was determined unaided and 6 months after initial fitting with the Freiburg test in quiet at 65 dB. Furthermore, the effective gain (EG) was determined.

Results All patients showed a significant improvement in speech recognition postoperatively. The actuator target structure had no significant effect on postoperative speech recognition at 65 dB (incus 75  ±  21 % , stapes head 67  ±  21 % , round window membrane 76  ±  20 % ). Patients with incus coupling offered a higher EG in the low frequency range than patients with round window and stapes coupling, whereas the EG was superior in the high frequency range in patients with stapes coupling.

Conclusion The analysis of the EG in the clinical setting reflects the transmission properties of the FMT known from experimental investigations. However, these differences do not significantly affect the postoperative speech recognition score.

Poster-PDF A-1571.pdf

Publication History

Article published online:
13 May 2021