Retrospective audiological analysis of bone conduction versus round window vibratory stimulation in patients with mixed hearing loss

Abstract

Objective: To compare audiological outcomes in mild-to-moderate mixed hearing loss patients treated with a bone-anchored hearing aid or an active middle-ear implant. Analysis aimed to refine criteria used in preoperative selection of implant type. Design: Retrospective comparative analysis of audiological data. Follow-up time ranged between 0.55 and 8.8 years. Study sample: For detailed comparative analysis, 12 patients (six in each group) with comparable bone conduction thresholds and similar clinical characteristics were selected. A larger cohort of 48 patient files were used to evaluate overall audiological indication criteria (24 per group). Results: In free-field tone audiometry, Baha patients showed mean aided thresholds between 40–48 dB, whereas hearing thresholds for VSB patients were 25–43 dB. Baha and VSB users had mean WRS of 56% and 82%, respectively, at 65 dB. Better speech understanding in noise was seen with the VSB. Conclusion: Analysis of the main cohort (n = 48) showed that treatment with round window vibroplasty leads to better hearing performance than treatment with a bone-anchored hearing device, if the bone conduction pure-tone average (0.5 to 4 kHz) is poorer than 35 dB HL. Audiological analysis in the smaller comparative analysis showed similar findings.

Key Words::

• Bone-anchored hearing aids
• active middle-ear implants
• Vibrant Soundbridge
• bone conduction
• round window vibroplasty
• mixed hearing loss

Acknowledgements

The authors would like to thank all subjects for their participation. This work was not financially supported in any form. Parts of this work were presented in 2013 at the 16th annual DGA meeting in Rostock, Germany.

Declaration of interest: The authors report no conflicts of interest and are solely responsible for the content of the paper.