SOME COMPOSITION OF THE IMPLANTABLE HEARING AID AND ITS FUNCTIONS

Abstract

Over a period of 3 years, the design policy and basic components of the implantable hearing aid for the artificial middle ear (AME) have been examined.
In vitro testing, most components were immersed and autoclaving in saline at 40°C. More than 200 days of development testing have been accumulated to date on the Fuloro-Carbon resin coated tiny vibrators, hermetically sealed Li/MnO₂ cells, Ni/Cd rechageable cells, electlet condenser microphones and amplifiers.
In vivo testing, during the period of April 1979 to October 1981, 17 vibrators, 9 microphones and 6 prototype AMEs were chronically implanted on the skull of cats. The vibrators and AMEs were evaluated with the auditory-evoked brain stem response, and the microphones were monitored with the percutaneous input signals.
The longest succesful implants of the present vibrators, microphones and AMEs are 510 days, 200 days and 130 days each.