Speech development and auditory performance in children after cochlear implantation

The aim of this study was to determine the auditory performanceof congenitally deaf children and the effect of cochlear implantation (CI) on speechintelligibility. Aprospective study was undertaken on 47 children in a pediatric tertiary referral center for CI. All children were deaf prelingually and were younger than8 years of age. They were followed up until 5 years after implantation. Auditory performance was assessed by using the categories of auditory performance (CAP) scaleand speech intelligibility rating which evaluated the spontaneous speech of eachchild before and at frequent intervals for five years after implantation. Pre-lingually deaf children showed significant improvement in auditoryperformance after implantation. Six months after implantation 91% of children hadthe ability to respond to speech sounds. At the end of year one, 96% of childrencould discriminate speech sounds and 84% of children who reached the three yearinterval could understand common phrases without lip-reading. After cochlear implantation, the difference between the speech intelligibility rating increased significantlyeach year for 3 years (p<0.05) and did not plateau up to 5 years after implantation.The changes in auditory performance and speech development were parallel. The results indicated the ability of cochlear implantations to significantly improve auditory receptive skills and subsequently speech development inyoung congenitally deaf children.