Researchers conducted a systematic review to identify audiologic thresholds in decibel hearing level (dB HLs) that might be appropriate for pediatric cochlear implantation. Children with a profound hearing impairment may benefit from cochlear implantation at audiology thresholds of 80 dB or higher, rather than 90 dB or higher, as is often recommended. The study was published in JAMA Otolaryngology Head-Neck Surgery.
They screened studies through June 2017 comparing speech and language development between profoundly deaf children using cochlear implants and those with severe hearing loss using hearing aids.
Out of 2,822 articles screened and evaluated, ten were included in the review. Two formulated audiologic thresholds at which children could qualify for cochlear implantation: (1) at 4-frequency pure-tone average (PTA) thresholds of 80 dB HL or greater based on speech perception and auditory performance subtests; and (2) at PTA thresholds of 88 and 96 dB HL, based on a speech perception subtest.
Children with profound hearing impairment using cochlear implants performed similarly to children with severe hearing impairment using hearing aids in 44% of various tests of overall intelligibility and correctly produced speech.
Cochlear implant users performed better than those with hearing aids on a picture-naming test and a speech perception in noise test. The author concludes that lower audiologic thresholds (80 dB HL or higher) that are advised in current national and manufacturer guidelines would be appropriate as audiologic candidacy criteria for pediatric cochlear implantation They acknowledge that they could not do a meta-analysis of findings due to the "large heterogeneity in the study population and selected tests.
Dr. Oliver Adunka, a pediatric otolaryngologist at Nationwide Children's Hospital and Director of Otology, Neurotology and Cranial Base Surgery at The Ohio State University Wexner Medical Center in Columbus, commented, "Our practice at this point is to implant toddlers and older children when they demonstrate a moderate-profound sensorineural hearing loss."
Further, a multidisciplinary evaluation is critical, and pure-tone thresholds are often not as relevant as other factors such as speech discrimination scores and, more importantly, speech production measures.
The heterogeneity of the cited literature limits the review and the fact that there has not been a clear agreed-upon reporting standard for pediatric cochlear implantation until very recently.
Studies indicate that lower audiologic thresholds (≥80 dB HL) that are advised in current national and manufacturer guidelines would be appropriate as audiologic candidacy criteria for pediatric cochlear implantation.