Speech Perception in Patients with Nucleus cochlear Implant

Abstract

The 22-channel cochlear implant was placed in 12 postlingual profoundly deaf patients since 1988. Psychological, physical, and speech functioning were investigated in 7 of the 12 patients, one year or more after surgery. The threshold level and maximum comfort level showed minimal changes even 4 years after first programming. The number of applicable electrodes (mean value, 17) was stable for over one year. Speech perception with and without lipreading was examined 3 months, 1 year and 4 years after first programming. Without lipreading, correct responses in the vowel test (mean, 67.1%) were better than in the consonant test (mean, 31.3%). Speech tracking scores with lipreading (18.5 phrases/min.) were considerably high for regular speech perception, and 3 of the 5 patients tested more than 4 years after surgery had excellent speech tracking scores (29 phrases/min.), which seemed to be very close to those with normal hearing. The other 2 patients did not use their cochlear implant systems much because of their limited social activity. It is concluded that the routine use of the implant system and/or adequate personal social activity are probably important factors in attaining acute speech perception.