Hannes Maier
Hannes Maier studied mathematics and physics at the Justus-Liebig-University Giessen, Germany. After the pre-diploma he continued is studies at the Université de Paris Sud, Orsay, France, before he received a Max-Planck fellowship at the Max-Planck-Institute of Biophysics, Frankfurt, Germany. There he worked there on the theory of interaction between electric fields and cells receiving his diploma in physics in 1987 and his PhD in 1993 from Johann-Wolfgang-v. Goethe-University Frankfurt, Germany. After a post-doctoral position at the Dept. of Otolaryngology, Hearing Research Laboratory, Tübingen University, Germany working experimentally on the micromechanics of the apical cochlea he was appointed Head of Audiology/Neurotology at the Dept. Otolaryngology, Hamburg Eppendorf University Medical School, Hamburg, Germany in 1998. From 2008 to 2011 he joined the start-up Phonak Acoustic Implants SA, Morges, Switzerland as senior research scientist for the development of an active direct acoustic cochlear implant. In 2012 he was appointed associate professor for Experimental Audiology in the Cluster of “Excellence Hearing 4all” and Head of the Acoustic Implants Team, Dept. Otolaryngology, Hannover Medical School, Hannover, Germany. His main areas of research are the audiological and experimental evaluation of active middle ear implants and bone conduction devices as well as the development of new acoustic implants.
Session
Research and clinical interest in cochlear implant (CI) electrode impedance have evolved significantly throughout 2024 and 2025. The current focus has shifted from simple "functionality checks" to using impedance as a sophisticated biomarker for the internal environment of the cochlea. In CIs, electrode impedance measurement plays a role in optimizing power requirements, establishing electrode integrity, and determining electrical stimulation parameters such as the pulse duration, pulse amplitude, and stimulation rate. Any changes in impedance levels may indicate issues with the electrodes and/or cochlear implants, such as short circuits, open circuits, or damaged devices. Long-term use of the device may lead to a reduction in its efficiency in delivering electrical current to the surrounding cochlear tissues, resulting in an increase in impedance and decreased implant effectiveness. Therefore, it is saliently important to perform follow-up examinations post-implantation to investigate potential changes in the electrical impedance of cochlear implants over time. On the other hand, early activation results in decrease of impedance and better voltage transmission across electrodes. This of course will improve the outcome performance of CI. Impedance Voltage Matrix an emerging tool provide a deeper insight on the electrode neural interface at each electrode. Different electrode impedance models are developing to be integrated into clinical practice using the standard software. All detailed related updates will be highlighted in the roundtable.