A retrospective study of cochlear implant outcomes in children with residual hearing

BACKGROUND: There has been increasing demand for the cochlear implantation of children who demonstrate some auditory capacity with conventional hearing aids. The purpose of this study was to examine speech recognition outcomes in a group of children who were regarded as borderline candidates for cochlear implantation as their residual hearing and/or auditory functioning levels exceeded typical audiologic candidacy criteria. METHODS: A retrospective chart review was undertaken at one Canadian cochlear implant centre to identify children implanted at age 4 or older with a pure-tone-average of 90 dB or better and speech recognition of 30% or greater. Pre-implant and post-implant open-set word and sentence test scores were analyzed. RESULTS: Eleven children of 195 paediatric cochlear implant recipients met the inclusion criteria for this study. Speech recognition results for the10 English-speaking children indicated significant gains in both open-set word and sentence understanding within the first 6 to 12 months of implant use. Seven of 9 children achieved 80% open-set sentence recognition within 12 months post-surgery. CONCLUSION: Children with several years of experience using conventional amplification demonstrated rapid progress in auditory skills following cochlear implantation. These findings suggest that cochlear implantation may be an appropriate intervention for selected children with severe hearing losses and/or auditory capacity outside current candidacy criteria

Pediatric cochlear implantation: an update

Deafness in pediatric age can adversely impact language acquisition as well as educational and social-emotional development. Once diagnosed, hearing loss should be rehabilitated early; the goal is to provide the child with maximum access to the acoustic features of speech within a listening range that is safe and comfortable. In presence of severe to profound deafness, benefit from auditory amplification cannot be enough to allow a proper language development. Cochlear implants are partially implantable electronic devices designed to provide profoundly deafened patients with hearing sensitivity within the speech range. Since their introduction more than 30 years ago, cochlear implants have improved their performance to the extent that are now considered to be standard of care in the treatment of children with severe to profound deafness. Over the years patient candidacy has been expanded and the criteria for implantation continue to evolve within the paediatric population. The minimum age for implantation has progressively reduced; it has been recognized that implantation at a very early age (12–18 months) provides children with the best outcomes, taking advantage of sensitive periods of auditory development. Bilateral implantation offers a better sound localization, as well as a superior ability to understand speech in noisy environments than unilateral cochlear implant. Deafened children with special clinical situations, including inner ear malformation, cochlear nerve deficiency, cochlear ossification, and additional disabilities can be successfully treated, even thogh they require an individualized candidacy evaluation and a complex post-implantation rehabilitation. Benefits from cochlear implantation include not only better abilities to hear and to develop speech and language skills, but also improved academic attainment, improved quality of life, and better employment status. Cochlear implants permit deaf people to hear, but they have a long way to go before their performance being comparable to that of the intact human ear; researchers are looking for more sophisticated speech processing strategies as well as a more efficient coupling between the electrodes and the cochlear nerve with the goal of dramatically improving the quality of sound of the next generation of implants

Neurocognitive testing and cochlear implantation: insights into performance in older adults

Maura K Cosetti,1,2 James B Pinkston,3 Jose M Flores,4 David R Friedmann,5 Callie B Jones,3 J Thomas Roland Jr,5,6 Susan B Waltzman5 1Department of Otolaryngology – Head and Neck Surgery, 2Department of Neurosurgery, 3Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA, 4Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MA, 5Department of Otolaryngology, 6Department of Neurosurgery, New York University School of Medicine, New York, NY, USA Objective: The aim of this case series was to assess the impact of auditory rehabilitation with cochlear implantation on the cognitive function of elderly patients over time. Design: This is a longitudinal case series of prospective data assessing neurocognitive function and speech perception in an elderly cohort pre- and post-implantation. Setting: University cochlear implant center. Participants: The patients were post-lingually deafened elderly female (mean, 73.6 years; SD, 5.82; range, 67–81 years) cochlear implant recipients (n=7). Measurements: A neurocognitive battery of 20 tests assessing intellectual function, learning, short- and long-term memory, verbal fluency, attention, mental flexibility, and processing speed was performed prior to and 2–4.1 years (mean, 3.7) after cochlear implant (CI). Speech perception testing using Consonant–Nucleus–Consonant words was performed prior to implantation and at regular intervals postoperatively. Individual and aggregate differences in cognitive function pre- and post-CI were estimated. Logistic regression with cluster adjustment was used to estimate the association (%improvement or %decline) between speech understanding and years from implantation at 1 year, 2 years, and 3 years post-CI. Results: Improvements after CI were observed in 14 (70%) of all subtests administered. Declines occurred in five (25%) subtests. In 55 individual tests (43%), post-CI performance improved compared to a patient’s own performance before implantation. Of these, nine (45%) showed moderate or pronounced improvement. Overall, improvements were largest in the verbal and memory domains. Logistic regression demonstrated a significant relationship between speech perception and cognitive function over time. Five neurocognitive tests were predictive of improved speech perception following implantation. Conclusion: Comprehensive neurocognitive testing of elderly women demonstrated areas of improvement in cognitive function and auditory perception following cochlear implantation. Multiple neurocognitive tests were strongly associated with current speech perception measures. While these data shed light on the complex relationship between hearing and cognition by showing that CI may slow the expected age-related cognitive decline, further research is needed to examine the impact of hearing rehabilitation on cognitive decline. Keywords: cognitive function, cognitive impairment, dementia, aging, hearing loss, cochlear implant, neuropsychological testin