CONTACTLESS SEMI-IMPLANTABLE ELECTROMAGNETIC MIDDLE-EAR DEVICE FOR THE TREATMENT OF SENSORINEURAL HEARING-LOSS - SHORT-TERM AND LONG-TERM ANIMAL-EXPERIMENTS

A contactless electromagnetic hearing device has been designed followi ng basic science experiments, improvement of electronics, and precisio n micromechanics. Different prototypes have been developed and tested in the laboratory, fresh human temporal bones, and acute and chronic a nimal experimentation. A conductive hearing loss model was first devel oped in the cat using samarium cobalt as the target magnet. Later, a h ighly efficient electromagnetic air-core coil was selected to vibrate a neodymium iron boron magnet cemented to the body of the incus and te sted in acute and chronic experiments using the cat as the model. In t his group of animals, the ossicular chain was left intact. There was n o failure of the target magnet, driving coil, or implanted electronics . The only problem encountered in this evaluation was a malfunction of the receiving antenna that had to be redesigned and retrofitted into the implanted units. This system would be suitable for the treatment o f moderate to severe sensorineural hearing loss. Planning to begin hum an clinical trials is ongoing.