[Results of cochlear implants in totally deaf subjects]

Cochlear implants have been applied on a limited scale in the Netherlands since 1985. In a government sponsored health service trial the method was further explored from 1988 to 1991. During this period 20 persons were implanted, ten with a Vienna extracochlear system and ten with a 22-electrode Nucleus intracochlear system. The ages varied from 5 to 62, the duration of deafness from 2 to 47 years. Some patients were congenitally deaf. The major cause of deafness was meningitis. The effect of the implantation was tested with the 'minimal auditory capability' test battery adapted for the Dutch language. 18 persons were wearing their system for more than 8 h a day; one person, a prelingually deaf did no longer use his implant while another one only used it occasionally. Except for two persons, all scored above chance level on several tests. The postlingually deaf persons with the Nucleus system all achieved a certain degree of open set speech understanding without lipreading. With the aim of achieving better selection criteria a new trial has started with the same financial sources in cooperation with the Utrecht University Hospital.