Extracochlear Eight- and 16-Channel Cochlear Implants with Percutaneous and Transcutaneous Transmission: Experiences with 129 Patients

Abstract

The Cologne-Düren research group has developed a multichannel extracochlear method of implantation and has carried out 129 operations as of June 1985. To simulate the basic physiologic principles of the inner ear, we also used the place and periodicity principle. Experience so far has shown that the electrical stimulus pattern is perceived as an auditory sensation by the bony wall of the middle ear, and that even a certain selectivity can be achieved. All 129 patients have attained acoustic contact with the environment. They can largely differentiate environmental noises and distinguish human voices from each other. Their lipreading is substantially improved with the support of the speech processor. Moreover, pronunciation becomes very much more distinct in the congenitally deaf. Apart from these average results, signs of development of open speech were observed in 11% of the patients.