A new coupling device for precise round window coupling of the Vibrant Soundbridge – First audiological results
23 April 2019 (online)
The FMT (Floating Mass Transducer) can be coupled to different parts of the ossicular chain or the round window membrane (RWM). For placing the FMT in front of the RWM biological as well as artificial materials have been used to improve the vibratory transmission into the cochlea. To overcome the undefined contact forces and standardize the procedure, the Hannover Coupler (HC) has been designed. The new design with a spring allows a precise and standardized RWM-coupling and exposes a constant and controllable preload of the FMT to the RWM. Our study shows the first audiological results of the patients, which have been treated with the improved version of the HC.
To assess the audiological outcomes pre- and post- operative hearing thresholds, Freiburg Monosyllables (FBM) 65 dB and the Oldenburg sentence test in quiet and in noise were performed up to 6 months. Additionally, questionnaires were performed to compare the general satisfaction and hearing status.
Seven patients have been implanted. It could be shown that the inner ear have not been affected by the surgical invention. The speech perception outcomes in the FBM were preoperative 0% and after 3 month 80%. Thresholds for speech intelligibility in quiet were measured with > 72 dB SPL preoperative and < 45 dB SPL after 3 month. Within the speech in noise test the speech level can be lower than the noise level (65 dB SPL). This was not possible bevor the implantation.
The new HC is a reliable and safe method for round window coupling. A precise and standardized placement of the FMT was possible during the surgical intervention. The inner ear function has not been affected and preliminary results show good speech perception outcomes in quiet and noise.