Developmental delay should not prevent implants for deaf children
MedWire News: Children should not be excluded from having cochlear implantation just because they have impaired cognitive development, say researchers.
Such developmental impairment may only be temporary and it is possible that these children will catch up after several years, say Harukazu Hiraumi (Kyoto University, Japan) and colleagues.
Previous studies have reported that children with developmental delays have poor development of speech perception skills after implantation. However, such studies have only compared the speech outcomes between delayed and nondelayed children, and not the relationship between the extent of pre-operative cognitive delay and outcomes, explains the team.
"It is necessary to examine the relationship between development and speech outcomes in each child," say the researchers.
In the current study, which included 35 prelinguistically deafened children who underwent multichannel cochlear implantation, 31% of the children were considered developmentally delayed, as defined by a score of less than 80 for the cognitive‑adaptive area on the Kyoto scale of psychologic development.
As reported in Auris Nasus Larynx, children who had delayed development before implantation had significantly lower speech perception scores 2 years later compared with children who had normal pre-operative development scores (>80 on cognitive‑adaptive area of Kyoto scale).
However, correlation analysis showed that the relationship between the development scores and the speech perception scores was weak, with large individual variability among children with similar developmental statuses, write the researchers.
Indeed, some children with developmental delays had speech perception scores that were similar to children without developmental delays, they report.
"This result seems reasonable because the outcome of the cochlear implantation can be influenced by several factors, including the habilitation program, technological improvements, and family characteristics."
The team concludes that it does not seem possible to define a developmental quotient cutoff level for the indication of cochlear implantation and it is not appropriate to exclude children for candidacy for cochlear implantation based only on a developmental delay.
By Sally Robertson