Performance of 2- and 3-year-old children and prediction of 4-year from 1-year performance.

OBJECTIVE: To examine whether children perform better when they receive cochlear implants when they are 2 to 4 years of age than when they are older, and to determine whether 4-year performance can be predicted from 1-year results. METHOD: Children in two age groups (2 to 4, 4 to 9 years) were tested for performance, and the age groups were compared. Children were also tested 1 and 4 years after implantation. RESULTS: The results suggest that the "implanted young" group scored higher than the "implanted old" group after 36 months, and that 1-year performance is helpful in predicting 4-year performance. CONCLUSION: It may be desirable for children to undergo implantation when they are under 2 years of age, provided that appropriate selection criteria can be determined.

Speech perception by prelingually deaf children using cochlear implants.

In this investigation we measured the performance of 50 prelingually deaf children on several speech perception tests. Children were from 2 to 15 years of age, and some children were tested with as much as 5 years of cochlear implant use. Speech perception tests included the recognition of stress pattern, consonants, vowels, words, and sentences. The audiovisual perception of consonants was also measured. Average results indicated that gains were being made in the perception of stress and words in a closed-set context within 1 year from implantation. The perception of words in an open-set context demonstrated much slower increases over time. Large individual differences were observed. Some preliminary data suggest that children who receive implants before the age of 4 years obtain higher scores, on average, than children who receive implants after the age of 5 years. Some children become part-time users or nonusers of their cochlear implants. The average results from 18 congenitally deaf children were significantly higher than the average results from 12 children with prelingually acquired deafness after 3 years of implant use. Information on vowel and consonant features shows increases in performance after 2 years of cochlear implant use, with the exception of the place feature. For this feature, no changes were observed. Vision-alone testing indicated that lipreading performance increased over time. An audiovisual enhancement provided by the cochlear implant was observed for all features.

Cochlear implant use by prelingually deafened children: the influences of age at implant and length of device use.

This study focused on long-term speech perception performances of 34 prelingually deafened children who received multichannel cochlear implants manufactured by Cochlear Corporation. The children were grouped by the age at which they received cochlear implants and were characterized by the amount of time they used their device per day. A variety of speech perception tests were administered to the children at annual intervals following the connection of the external implant hardware. No significant differences in performance are evident for children implanted before age 5 compared to children implanted after age 5 on closed-set tests of speech perception ability. All children demonstrated an improvement in performance compared to the pre-operative condition. Open-set word recognition performance is significantly better for children implanted before age 5 compared to children implanted after age 5 at the 36-month test interval and the 48-month test interval. User status, defined by the amount of daily use of the implant, significantly affects all measures of speech perception performance except pattern perception.

Results of multichannel cochlear implants in congenital and acquired prelingual deafness in children: five-year follow-up.

Postlingually deafened children, using multichannel cochlear implants, have achieved substantial improvement in their speech perception abilities and, in many instances, the results are better than in postlingually deafened adults. It has been suggested that children with prelingually acquired and congenital deafness would not receive similar benefits, since they have not developed an auditory memory. The purpose of this study is to analyze the speech perception and production performance over time of prelingually deafened children who have been using a multichannel cochlear implant for 1-5 years. Preliminary results comparing the effects of age at implantation and etiology of deafness on performance are also examined.

Intraoperative and postoperative electrically evoked auditory brain stem responses in nucleus cochlear implant users: implications for the fitting process.

Electrically evoked auditory brain stem responses (EABR) were measured in 12 adults and 14 children with the Nucleus cochlear implant. Measures were made both intraoperatively and several months following surgery. EABR thresholds were consistently greater than clinically determined measures of behavioral threshold (T-level) but less than maximum comfort levels (C-level). When the data were pooled across subjects and different stimulating electrodes, EABR thresholds were strongly correlated with both T- and C-levels. In subjects where both intraoperative and postimplant EABR measures were obtained, intraoperative EABR thresholds were consistently higher than postimplant thresholds. The electrophysiologic data have been incorporated into a practical procedure for programming the implant in young children.

Performance over time of congenitally deaf and postlingually deafened children using a multichannel cochlear implant.

The speech perception performance of 10 congenitally deaf and 3 postlingually deafened children who received the Cochlear Corporation multichannel cochlear implant was examined and compared. The children were tested preimplant and at 6-month intervals up to 2 years using the Monosyllable-Trochee-Spondee test (MTS), the Word Intelligibility by Picture Identification test (WIPI), and Phonetically Balanced Kindergarten (PB-K) or Northwestern University List 6 (NU-6) word lists. The postlingually deafened children exhibited significantly improved performance on open- and closed-set tests of word recognition after 6 months of implant use, a pattern similar to that of postlingually deafened adult implant users. In contrast, the congenitally deaf children did not exhibit measurably improved performance on speech perception tests until after 12 months or more of implant use. With as much as 18-24 months of use, however, some congenitally deaf children demonstrated limited open-set word recognition.

Evaluation of a tactile aid and a cochlear implant in one child.

The speech perception and production skills have been examined in a young deaf child who used a tactile aid for 2.5 years and subsequently received a multichannel cochlear implant. Although the differences were small, there was a trend of higher performance on nearly all speech perception measures following implantation than was observed after 2.5 years of tactile-aid use. Negligible changes occurred in her speech while wearing the tactile aid but substantial improvements appeared after she had used the multichannel implant for only 6 months.