Maximum output determination of a transcutaneous active bone conduction implant

Introduction The maximum output of a bone conduction device (BCD) is one of the main factors that determines the success when treating patients with conductive or mixed hearing loss. Here, we introduce a method to determine the maximum output hearing level (MOHL) of a transcutaneous active BCD using patients’ audiological data.

Method We determined the maximum output in terms of hearing level MOHL [dB HL] of the Bonebridge using the bone conduction (BC) and direct threshold of the patient together with corresponding force levels at hearing threshold and the maximum force output of the device. Patients implanted with the Bonebridge between 2011 and 2021 were included in this study. The analyses of MOHLs were performed by separating the MOHLs based on better or worse frequency-by-frequency specific BC thresholds on the ipsilateral (implanted) side.

Results The average ipsilateral MOHLs were in the range between 51 to 73 dB HL for frequencies from 0.5 to 6 kHz in the group with better BC threshold on the ipsilateral ears. The average contralateral MOHLs in the group with better contralateral hearing were in the range from 43 to 68 dB HL. The variability of the data was approximately 7 to 11 dB (standard deviations) across measured frequencies (0.5-6 kHz). The average MOHLs were up to 8 dB higher across frequencies in the group with better BC threshold on the ipsilateral ears than in the group with better BC threshold on the contralateral ears. The differences between groups were significant across measured frequencies (t-test; p < 0.05).

Conclusion Our proposed method uses the direct and bone conduction threshold data of the patients from clinical routine to determine the frequency specific MOHL.

This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2177/1 – Project ID 390895286.”

Publication History

Article published online:
12 May 2023