FRIDAY, May 11 (HealthScout) -- While the electronic hearing devices called cochlear implants do the most for infants who are born deaf, they also can benefit profoundly deaf older children, adolescents and even adults, researchers report.
A study of 14 congenitally deaf adults and 35 deaf children between the ages of 8 and 14 found that cochlear implants improved their recognition of words, sentences and speech in general, even with a noisy background, says Dr. Noel L. Cohen, director of the cochlear implant program at New York University.
Cohen plans to present his research Sunday at the spring meeting of the American Neurotology Society in Palm Desert, Calif.
"This was a group of candidates who we thought would be the worst-case scenario," Cohen says. "They were all born deaf and did not get an implant until they were older. The children and adolescents had passed through what is generally regarded as the window of opportunity."
A cochlear implant is a tiny amplifier designed to help someone who has a paucity of sound-detecting cells in the ear. The implant increases the input to any remaining cells, so that signals will be transmitted through nerves to the brain.
The study was born because of requests made by parents of deaf children and by deaf adults who came to NYU asking for help, Cohen says.
"Parents of deaf adolescents who were in the regular school system described the struggle a child was having as the only deaf person in the class," he says. "They would ask if we could give them a little bit of hearing to supplement their lip-reading."
After the implants were done, standard tests did not show many benefits, Cohen says. "But the recipients were happy with the results, which was a bit of a puzzle until we realized that the tests were at fault," he says. "Now we have more sensitive tests using modern technology, and they demonstrate that the recipients do do better."
Among the adult recipients, 71 percent had improved recognition of one-syllable words and half had improved recognition of sentences. More than 60 percent reported improved sentence recognition in a noisy background. The children had comparable gains, although the rate of improvement was greatest for the younger children.
While early implantation produces the best results, "this study widens the horizon for cochlear implants," Cohen says.
In a sense, the study means that the wheel has come full circle, says Peg Williams, executive director of the Cochlear Implant Association.
"The first implants were done in adults in the late '70s or early '80s," Williams says. "They wanted to do adults first because the adults could give information about what was happening. They could relate their experience to the surgeon, which children could not do easily."
As the implants proved successful, they were given to children, starting with older ones, she says. The results proved rewarding, so "as surgical techniques improved and the technology improved, younger and younger children were given implants."
There still are many deaf adults who have not been candidates for implants because of the stage-by-stage development of the field, Williams says. "These are adults who have lived many years without hearing," she says.
Those who get implants usually appreciate them, she adds. "What I have heard myself is that these people very much enjoy hearing," Williams says. "They like to hear environmental sounds; they appreciate things like music. Basically, it implies a better quality of life, it puts them more in touch with the world at large."
But there is resistance to the implants by some members of the deaf community, she notes. "People who have been deaf all their lives and have children who are deaf say their children can be raised happily in a culture without hearing."
What To Do
New parents should be alert for the signs of infant hearing problems, which could be helped by a cochlear implant or other intervention. Adults who are deaf or whose older children have severe hearing problems can also inquire about cochlear implants -- not only whether they can help, but whether you would want them in the first place.
Primers on cochlear implants are available from the American Academy of Otolaryngology and the National Institute on Deafness and Other Communicative Disorders. Another source is the Cochlear Implant Association.
Try other HealthScout articles about the deaf.
