Cochlear Implants for Kids: Earlier Surgery Works Best
Study Identifies a Window of Opportunity for Cochlear Implants in Deaf Children
April 20, 2010 -- The sooner children with hearing loss receive cochlear
implants, the better, according to new research in the April 21 issue of the
Journal of the American Medical Association. Children who receive
cochlear implants before 18 months of age are better able to hear, comprehend
sound and music, and speak than are their counterparts who receive the implants
at a later age.
“Early-onset deafness is a common childhood disability that we can do
something about,” lead study author John Niparko, MD, the director of otology,
neurotology & skull base surgery at Johns Hopkins Medicine in Baltimore,
says in an email. “Using this technology in a strategic manner appears to carry
profoundly positive effects.”
What Are Cochlear Implants?
Often referred to as “bionic ears,” cochlear implants are much different
than hearing aids, which only amplify sounds. By contrast, cochlear implants
bypass damaged parts of the ear and stimulate the auditory nerve. The implant
generates signals that are sent to the brain via the auditory nerve. The brain
then recognizes these signals as sound. These small electronic devices consist
of an external component that sits behind the ear, and a second part that is
surgically placed under the skin.
Hearing loss can completely disrupt a child’s ability to learn to talk and
understand what people are saying, Niparko says. “Children normally begin to
pair the sounds of speech with meaning between six months and one year, [but]
if a child cannot hear the full range of speech sounds at this age, the
opportunities of learning speech and reflecting their thoughts by talking begin
to diminish,” he says.
Earlier Implants Can Close Language Gap
Enter cochlear implants.
In the new study, 188 children aged 6 months to 5 years were followed for
three years after they received cochlear implants. Researchers then analyzed
their language development and compared it to that of 97 children without
Children who received the implants before they turned 18 months showed
speaking ability that stayed close to that of their hearing counterparts, the
study showed. Children who received the cochlear implant after they turned 3,
however, still exhibited some gaps when compared to same-age children without
For each year that a child with hearing loss does not receive a cochlear
implant, they will lag behind in the rate of improvement in language
development, Niparko and colleagues write.
“Children who receive the cochlear implant early and are supported with
experiences that engage their interest through speech can overcome early
deprivation effects,” he says. “Their rate of learning to understand and
produce speech can approximate those of hearing children.”
The more support and interaction from caregivers and loved ones, the greater
the benefit, the study showed.
“If you have a child who has severe hearing loss in both ears, implanting
earlier is associated with better language and speech outcomes and less of a
gap versus kids with normal hearing,” says Kay W. Chang, MD, an associate
professor of otolaryngology at Stanford University and a pediatric cochlear
implant surgeon at Lucile Packard Hospital of Stanford University in Palo Alto,
Everyone can benefit from cochlear implants, but the kids that were younger
when they received the implants benefited more, he says. “This highlights the
importance of the early identification of kids with hearing loss.” Early
diagnosis coupled with implant evaluation by a team that includes a speech
pathologist, an audiologist, a child psychiatrist, and a surgeon is needed to
make sure children can receive cochlear implants in a timely manner.