by Erin Digitale
Doctors should reconsider the common practice of avoiding the use of cochlear implants in deaf children with developmental delays, according to a new study from the Stanford University School of Medicine and Lucile Packard Children’s Hospital.
While cochlear implants are now routinely given to deaf children as young as 1 year old, physicians frequently opt not to use these devices — sometimes referred to as “bionic ears” — in babies with developmental delays that are indicators of probable mental retardation later in life. But the new findings suggest that the implants could substantially benefit these children’s intellectual development, even if their cognitive problems make it unlikely that they will ever learn to speak.
“If we can fix this deficit, it might help developmentally delayed children in other ways outside of hearing,” said John Oghalai, MD, the lead author of the study, which appears in the August issue of Otology & Neurotology. Oghalai is an associate professor of otolaryngology at Stanford and the director of the Packard Children’s Hearing Center.
The combination of deafness and developmental delay has become more common as increasing numbers of children survive extremely premature birth; complications of prematurity often include both cognitive delays and deafness.
But providing cochlear implants for developmentally delayed children has often taken a back seat to their other medical issues, Oghalai said. These children may be grappling with congenital heart defects, an inability to eat by mouth or serious breathing problems, for example, and doctors may not want to complicate their treatment with yet another procedure.
Physicians also have been wary of whether the implants would benefit the children. Cochlear implants send electronic signals from a microphone on the outside of the head directly to the auditory nerve, but the result is different from normal human hearing, and children typically require intensive speech and auditory therapy to learn to use and benefit from the implants.
For the study, Oghalai and his colleagues assessed use of cochlear implants in children who were cognitively normal and those who were developmentally delayed, a term used to characterize young children who may later meet criteria for mental retardation. The researchers reviewed records of 60 developmentally delayed and 144 cognitively normal children who received the implants, and found that the cognitively normal children got cochlear implants earlier in life than the developmentally delayed children. The former, on average, received them at 16 months of age vs. 25 months of age on average for the latter.