Objectives: To evaluate the long-term outcome of children with postmeningitic deafness and partial insertion of the Nucleus electrode array, and to compare their speech perception performance with that of children with full insertion of the electrode array.
Design: A battery of seven speech perception tests was administered to 25 children with a cochlear implant (CI). Results were reduced into one score: equivalent hearing loss (EHL).
Setting: Tertiary referral centre.
Participants: The partial insertion group comprised seven children, mean age at implantation 5.5 years, mean duration of deafness 3.6 years. The full-insertion control group comprised 18 children. Mean age at implantation: 4.4 years; mean duration of deafness: 2.9 years. All the children became deaf between 0 and 3 years of age.
Main outcome measures: Over a 3-year follow-up period, the children with partial insertion showed continuing progress, although there was wide variation in performance and the rate of progression. Some open-set comprehension could even be achieved with the insertion of only eight electrodes of a nucleus device.
Results: Three years after implantation, speech perception in the partial insertion children was poorer than that in the control groups with long (P < 0.01; 95% confidence interval 7-43 dB EHL) and short duration of deafness (P < 0.0001; 95% confidence interval 28-53 dB EHL). They showed slower progress and reached a poorer EHL plateau. Four of the seven children acquired open-set word recognition.
Conclusions: Patients with partial insertion of the electrode array benefit from a CI, although less than patients with complete insertion.