Multichannel Cochlear Implant: The New York University/Bellevue Experience

Abstract

A total of nine patients have been implanted at the New York University/Bellevue Medical Center with the Nucleus multichannel cochlear implant. The patients ranged in age from 21 to 62 years, with a mean age of 38.7 years. All were postlingually deafened with bilateral profound sensorineural hearing loss, and were unable to benefit from appropriate amplification. Each patient was implanted with the 22-electrode array inserted into the scala tympani, using the facial recess technique. Seven of the nine patients have functioning 22-channel systems, whereas one patient has a single-channel system and one had 14 electrodes inserted because of an unsuspected obstruction in the scala tympani. All patients are regular users of the device and none have been lost to follow-up. Seven patients have completed the prescribed Nucleus training program, and two patients are in the early stages of training. All nine patients have shown a restoration of hearing sensation in response to acoustic stimuli and a recognition of a wide variety of environmental sounds. All seven patients who have completed training and are using the multichannel stimulation have shown an improvement in their vowel and consonant recognition scores when the implant is used in conjunction with lipreading. Mean speech-tracking scores for these patients show an improvement from lipreading alone to lipreading with implant of 28.8 to 60.6 words per minute. Patients also demonstrated a consistent increased ability to use suprasegmental information and to obtain closed set work recognition on portions of the Minimal Auditory Capabilities test battery. Several of the patients have shown an ability to understand significant amounts of open set speech without lipreading. Two patients can comprehend noncoded telephone conversation; one scores an average of 42% on open set speech discrimination testing and the other 20% using the W22 word list with audition only.