The impact of bilateral implantation on language outcomes
Reviewed by Kerri Millward & Morag Lockley

An American study retrospectively looked at the language outcomes of 204 children implanted either bilaterally, sequentially or unilaterally. All children received their first implant before the age of three years, and language measures were collected when the children were aged between three and five years. Some of the unilaterally-implanted children also wore a hearing aid (bimodal), but their average unaided thresholds were 101 dBHL, so they were counted in the unilateral numbers. All participants had good aided levels with their cochlear implant(s) (between 20 and 30 dBHL) and undertook a variety of age-appropriate language tests measuring both expressive and receptive language. As a whole, age of implantation was an important factor, agreeing with many studies showing that earlier implantation results in better outcomes. However, group was also a factor, showing that those implanted bilaterally did better on the outcome measures than those implanted unilaterally. This is an important finding as bilateral implantation is not offered universally across the globe. The type of health insurance was also a factor, which could give an indication that socio-economic status also played a part. Those on government scheme insurance performed significantly worse than those with private health coverage. This study has shown that it is important to be aware of the possible impact of all these factors when counselling families who are considering cochlear implantation.

The impact of unilateral, simultaneous, or sequential cochlear implantation on paediatric language outcomes.
Eskridge HR, Park LR, Brown KD.
COCHLEAR IMPLANTS INT.
2021;22(4):187-94.