Utilizing the cochlear implant for single-sided deafness

For children with hearing loss, the cochlear implant has been a path to hearing. The device was recently approved for children who had single-sided deafness, but little was known about whether it improved outcomes in this patient group. A systematic review and meta-analysis in JAMA Otolaryngology- Head & Neck Surgery offers some much needed evidence.¹

The researchers searched MEDLINE, Embase, Scopus, Cochrane, and PubMed to find English-language articles. They selected articles that examined patients younger than 18 years, looked at patients with a diagnosis of single-sided deafness that led to cochlear implantation, and included at least 1 outcome that was measured numerically, such as sound localization or device use. The main outcomes included postoperative changes in speech perception, patient-reported audiological outcomes, and device use rates.

There were 12 observational studies that met their criteria and the studies included 119 children with single-sided deafness who had been given a cochlear implant. Many of the children illustrated improvement in speech perception which was clinically meaningful in noise (in noise, 39 of 49 children [79.6%] and in quiet, 34 of 42 children [81.0%]). For children who had a lack of improvement, the most commonly proposed reason was long duration of deafness (>4 years in congenital single-sided deafness and >7 years in perilingual single-sided deafness). A statistically significant improvement was found in sound localizations, as measured by degrees of error from the sound’s true location, following cochlear implantation (mean difference [MD], –24.78°; 95% CI, –34.16° to –15.40°; I2 = 10%). The investigators found that patients with acquired single-sided deafness and shorter duration of deafness when compared to patients with congenital single-sided deafness had bigger improvements in speech (MD, 2.27; 95% CI, 1.89-2.65 vs 1.58; 95% CI, 1.00-2.16) and spatial (MD, 2.95; 95% CI, 2.66-3.24 vs 1.68; 95% CI, 0.96-2.39) hearing qualities. Additionally, duration of deafness among device nonusers was found to be longer than the duration of deafness among patients who regularly used the device (median difference, 6.84; 95% CI, 4.02-9.58).

The researchers concluded that cochlear implants given to children who have single-sided deafness were linked with both clinically meaningful audiologic improvements and better patient-reported outcomes. They also concluded that shorter durations of deafness could be linked with better overall outcomes.

Reference

1. Benchetrit L, Ronner E, Anne S, Cohen M. Cochlear implantation in children with single-sided deafness. JAMA Otolaryngology–Head & Neck Surgery. November 5, 2020. Epub ahead of print. doi:10.1001/jamaoto.2020.3852