Evaluation of implantable actuators by means of a middle ear simulation model

Research output: Contribution to journalResearch articleContributedpeer-review



The extension of indication of implantable hearing aids to cases of conductive hearing loss pushed the development of these devices. There is now a great variety of devices available with different actuator concepts and different attachment points to the middle ear or inner ear fluid. But there is little comparative data available about the devices to provide an insight into advantages and disadvantages of different types of actuators and attachment points at the ossicular chain. This paper investigates two principle (idealized) types of actuators in respect of attachments points at the ossicular chain and direction of excitation. Other parts of implantable hearing aids like microphone, amplifier and signal processing electronics were not incorporated into this study. Investigations were performed by means of a mathematical simulation model of the middle ear (finite element model). Actuator performance and theoretical gain were calculated by harmonic analysis in the frequency range of 100-6000 Hz and were compared for the different situations. The stapes head proofed to be an ideal attachment point for actuators of both types as this position is very insensitive to changes in the direction of excitation. The implantable actuators showed higher ratio of equivalent sound pressure to radiated sound pressure compared to an open hearing aid transducer and should therefore allow for more functional gain.


Original languageEnglish
Pages (from-to)145-151
Number of pages7
JournalHearing Research
Issue number1-2
Publication statusPublished - May 2010

External IDs

Scopus 77952581876
PubMed 20156543
ORCID /0000-0002-3061-0171/work/142241283
ORCID /0000-0003-3894-1175/work/148603669


Sustainable Development Goals


  • Acoustic Stimulation, Computer Simulation, Ear, Middle/anatomy & histology, Finite Element Analysis, Hearing Loss, Conductive/physiopathology, Humans, In Vitro Techniques, Models, Anatomic, Models, Biological, Ossicular Prosthesis, Prosthesis Design, Stapes/physiology, Transducers, Vibration