Vaccination rates in cochlear implant patients: a review of paediatric recipients.

OBJECTIVE: This study aimed to investigate whether children with cochlear implants received the recommended vaccinations according to New Zealand national immunisation guidelines and to report the incidence of meningitis in this population after intervention. METHOD: A retrospective review of the vaccination coverage of paediatric patients receiving cochlear implants between 2005 and 2019 was performed. RESULTS: Data were collected on 203 children. Evidence of immunisation against Haemophilus influenza B was documented in 94.1 per cent of this cohort and 21.2 per cent received the seasonal influenza vaccine. The pneumococcal conjugate vaccine was fully administered in 81.8 per cent of children; however, only 16.9 per cent of eligible children had received the pneumococcal polysaccharide vaccine. There was marked improvement in compliance to the pneumococcal conjugate vaccine once it became fully funded for cochlear implant patients. CONCLUSION: Despite established guidelines, the paediatric vaccination rates were less than expected. Work is in progress to address this.

A longitudinal study of electrode impedance, the electrically evoked compound action potential, and behavioral measures in nucleus 24 cochlear implant users.

OBJECTIVE: The primary goal of this study was to examine changes that may occur in electrode impedance, electrically evoked compound action potential (EAP) threshold and slope of the EAP growth function, and behavioral measures of threshold T-level) and maximum comfort (C-level) over time in both adult and child cochlear implant users. Secondary goals were to determine whether changes in these measures are consistent between children and adults, and to determine whether behavioral measures (MAP T- and C-levels) and electrophysiologic measures (EAP thresholds) exhibit the same trends over time. DESIGN: Thirty-five children and 33 adults implanted with the Nucleus CI24M between November 1996 and August 1999 participated in this study. Subjects were included in this study if 1) they had used their implant for at least 1 yr after device connection, and 2) they had participated in the necessary data collection at a minimum number of the time intervals assessed in this study. EAP threshold, slope of the EAP growth function, and common ground electrode impedance measures were collected intraoperatively, at initial stimulation, and at several subsequent visits up to 2 yr post initial stimulation. MAP T- an d C-levels weremeasured at initial stimulation and at the same time intervals as described above. RESULTS: Changes in electrode impedance, EAP thresholds, and slope of the EAP growth function from measures made intraoperatively, at initial stimulation, and at 1 to 2 mo post initial stimulation were similar in both children and adults. Beyond the 1- to 2-mo visit, children exhibited significant increases in electrode impedance, EAP thresholds, slope, and MAP T-levels, whereas these samemeasures in adults remained relatively stable. EAP thresholds in children stabilized by the 3- to 8-mo visit, and electrode impedance stabilized by the 6- to 8-mo visit, while slope of the EAP growth function, MAP T-levels,and MAP C-levels werestable by 1 yr post initial stimulation. C-levels in adults increased up to 1 yr post initial stimulation; however, the amount of increase was much smaller than that seen in children. In both children and adults, longitudinal trends in EAP thresholds mirrored T-level more closely than C-level. CONCLUSIONS: The results of this study suggest that peripheral changes occur in many children that do not generally occur in adults within the first year of cochlear implant use. One implication of these results is that if EAP thresholds are to be used to assist in programming the speech processor for children, it is best to make those measures at the same time interval as device programming rather than using measures made intraoperatively or at the initial programming session to set MAP levels at later visits.

Pre-lingually deaf children can perform as well as post-lingually deaf adults using cochlear implants.

Both pre-lingually deaf children and post-lingually deaf adults benefit from cochlear implants. These adults have a memory for speech sounds, but the children do not. In this preliminary investigation, we asked whether it was possible for these children to obtain high scores similar to the adults. We compared 21 prelingually deaf children to 81 post-lingually deaf adults using multichannel cochlear implants on the same test of sentence recognition. The children were selected to have the vocabulary and language sufficient to complete the test. Scores from the children, ranged from 0 to 97% correct. About one half of the children scored above 70% correct. Scores from the adults ranged from 0 to 100% correct with about one half of the adults scoring over 60%. Many of the children are scoring as well or better than adults are scoring. We conclude that the auditory system of pre-lingually deaf children is sufficient to obtain levels of speech recognition similar to post-lingually deaf adults.