Evaluation of middle-ear implant: a six-month observation in cats

The efficacy of a middle-ear implant was evaluated by measuring auditory brain stem responses. Middle-ear implants, including an input-transducer, an amplifier, a battery and an output-transducer, were implanted in cats. Most of the implants were kept functioning for a six-month period. Observation on the characteristics of these implants during this time showed allowable changes in an implant, now being prepared, for use in human subjects.