The changing profile of paediatric cochlear implantation over 26 years at the Sydney Cochlear Implant Centre – age at implant, unilateral vs bilateral, and radiological findings

Dr Kirsty Gardner-berry1, Associate Professor Catherine Birman1, Ms Rachelle Hassarati1, Mrs Maree McTaggart1

 1Sydney Cochlear Implant Centre, Gladesville, Australia


From 1992-2018 over 450 infants received cochlear implants under 2 years of age.  During this time the number of infants receiving implants increased over 10-fold, and the age at cochlear implantation steadily decreased.  Changes in funding also resulted in a significant increase in sequential bilateral implantation in 2007, followed by an increase in simultaneous bilateral implantation in 2012.

Improvements in the quality of radiological imaging has highlighted the variations in anatomy seen in children receiving cochlear implants.  Abnormalities in the structure of the cochleas and/or auditory nerves was noted in 15% and 13% of infants respectively.

Whilst newborn hearing screening, and increased funding for cochlear implants has enabled more infants to receive bilateral cochlear implants at a younger age, the potential impact of structural abnormalities of the cochlea and/or nerve on the quality of sound perceived through a cochlear implant needs careful consideration when counselling parents about realistic outcomes.


Kirsty is a diagnostic audiologist at the Sydney Cochlear Implant Centre, and clinical consultant for Scanmedics in the area of newborn hearing screening.  Kirsty has a Bachelor of Science, Masters in Audiology and PhD.  Kirsty’s specialty areas are electrophysiological testing and early identification of hearing loss.

Since the introduction of newborn hearing screening, the age at diagnosis of hearing loss has decreased significantly.  Research has also shown significantly better language outcomes in children implanted under 12 months of age.  This presentation describes the changes in age at implantation and candidacy evaluations over the last 26 years at the Sydney Cochlear Implant Centre, and summarizes the radiological findings that can impact on outcomes.