[The development of vocabulary capability at 2-year follow-up in the prelingual deaf children with cochlear implants]

To investigate the development of early vocabulary capability in the prelingual deaf children after cochlear implantation (CI) , and to study the feasibility of current Chinese assessment procedures about language development for hearing-impaired children.

A total of 56 cases with severe-to-profound prelingual deaf children were participated in this study. The vocabulary development of CI children were evaluated by trained audiologists using the vocabulary assessment tools: Chinese communicative development inventory (CCDI) and mandarin expressive and receptive vocabulary test (MERVT). The questionnaire assessed by parents or guardians answered the questionnaire; vocabulary tests were evaluated by children accompanied with audiologists. Patients were assessed before operation and in 2 years after switch-on.

With the rehabilitation, early post-operative vocabulary development gradually improved. The vocabulary increased with an increase in the duration of CI use, and the receptive vocabulary developed earlier than the expressive ones.

After 2 years of CI use, the child partly developed the vocabulary capability. Children's vocabulary test, CCDI and MERVT test, is an important index to evaluate the development of children's language ability after cochlear implantation. Vocabulary test, together with auditory and speech perception assessment procedures, constitute a more complete auditory-speech-language evaluation system for Chinese children after cochlear implants.