Breaking Sound Barriers : Health: The cochlear implant, now approved for children, helps the deaf function in hearing world. But the device is costly and difficult to use.

Casey Correia was 5 when he lost his hearing as a complication of meningitis, an inflammation of the membranes surrounding the spinal cord or brain. Hearing aids were of no use to the Yorba Linda boy. Within weeks of becoming deaf, his speech deteriorated.

Frankie and Jack Correia seized upon the only remaining alternative for their son: a cochlear implant. The device includes a small component surgically implanted in the inner ear and an external component resembling a conventional hearing aid, along with a small battery pack.

Casey, a patient at the House Ear Institute in Los Angeles, was the first child in North America to receive the cochlear implant. In 1986, when he underwent the surgery, the device was still experimental.

The months after the procedure were discouraging. The sounds Casey heard through his implant barely resembled those he remembered. In classes at a school for the deaf and at home, he struggled to make sense of the strange sounds--similar to a radio that needed tuning--produced by the implant.

“About nine months after he got the implant, I was in the kitchen and he was watching television with his back to me. I called his name and he turned around,” Frankie says. “It was like opening the door a little bit. I told him, that’s what your name sounds like.”

Since then, Casey, now 9, has become a model for what is possible with a cochlear implant. Slender and blond, with sparkling brown eyes and a nonchalant attitude regarding his fame, Casey now attends a regular school. By piecing together what he hears through the implant and by lip-reading, he functions normally in the hearing world.

“I didn’t want to wear it at first,” Casey says, shrugging. “But I started getting better at it.”

Success stories like Casey’s helped pave the way for the June approval by the U.S. Food and Drug Administration of the cochlear implant for children. The device, which was approved for adults in 1985, can now be prescribed for children as young as 2, if they meet stringent qualifications.

The FDA decision increases the chances that patients will receive insurance reimbursement for the costly device and enables dozens of hospitals to provide it. Previously, children could receive the implant at only the few medical centers charged with studying it.

More important, says Dr. Carol Jackson, a member of the FDA advisory panel that approved the device for children: “The hope is to eliminate the inevitability of a child born deaf to be committed to a life of silence.”

But the approval has renewed a long, emotional debate in the deaf community about the social impact of the device on children and its practical value to people of any age.

Some critics in the deaf community charge that parents who seek implants for a deaf child are steering the child into the hearing culture instead of accepting the child’s deafness and the culture and lifestyle that accompany it.

A broader criticism centers on whether the implant performs well enough to justify the expense--$25,000 to $40,000--and the intense training required to use it.

According to Lisa Tonokawa, an audiologist and coordinator of the children’s program at the House Ear Institute, the ultimate value of the cochlear implant for children varies widely and depends greatly on the amount of training and support from parents and teachers.

“We are not curing their hearing loss,” says Tonokawa, who has worked with the device for seven years. “There is still a lot of rehabilitation and a lot of extra work involved on the parents’ part. If they are not willing to do that then we shouldn’t implant the child because it will make no difference in the child’s life.

“I hate to sound so negative, because sometimes it does seem like a miracle. But (the) kids I get real excited about are those with parents who have worked really hard.”

The cochlear implant, invented more than two decades ago by Australian researchers, is for people who are born deaf or have such profound hearing loss that they receive no benefit from hearing aids.

While hearing aids receive and amplify sounds, cochlear implants receive, process and, bypassing the injured part of the ear, deliver sound information to the brain.

Sounds are picked up by a microphone worn behind the ear and routed to a speech processor, a calculator-sized box that is worn on a harness or clipped to a belt or pocket. The processor amplifies, filters and digitizes the sounds, then sends coded information to a receiver-stimulator, the tiny device implanted in the inner ear.

The receiver-stimulator converts the code to electrical signals and passes the signals to electrodes. The electrodes stimulate hearing nerve fibers, which the brain then picks up and recognizes as sound.

Because the implant delivers sounds only marginally similar to natural sound, months or years of training are required to maximize its benefits. Implant recipients must learn to link the sounds to events. For example, at first a recipient might not recognize a sound as the doorbell. After repeated exposure, however, the sound becomes familiar as that of the doorbell.

“I see a very big range of what kids do with the implant,” Tonokawa says. “You see some little kids take off and develop speech and language. But these are kids with very good school support and dedicated parents.”

Frankie Correia remembers following her son around and labeling each sound he heard.

“The first time we heard the dog bark I told him ‘That’s what it sounds like,’ ” she says.

And, she says, Casey also received more than two years of auditory training at a school for the deaf.

“The actual training occurs outside of the medical system with usage,” says Jackson, an associate professor and director of neurology at UCI Medical Center. “We don’t know in advance where the child will fit in. At a minimum, virtually all patients will detect medium to loud sounds, including speech. Some can detect certain words in a sentence without lip-reading.”

Some children also develop understandable speech, but, Jackson adds: “It doesn’t mean they don’t need speech therapy and other tutorial help.”

Experts agree that the patients who do the best with the implant are children who, like Casey, were deaf for a short time before receiving it. But studies have shown that even children who are born deaf can benefit, especially if they receive the device at age 2 or 3.

“Children are able to do so much with so little,” Jackson says. “What’s particularly surprising is how well children with congenital loss do compared to adults with congenital loss.”

According to Jackson, research on the implant in congenitally deaf children has yielded some interesting information about hearing development. For instance, young children appear to learn to use the implant quickly because their sensory functions are in a rapid stage of growth and development.

“They are learning to adapt to their environment, in general,” Jackson says. “There is another theory that sound input serves some nurturing role to the hearing system. With children, when you provide that sound early, you can promote more development.”

Tonokawa agrees that congenitally deaf children may benefit from the implant, although it may take them longer to master than children who lost their hearing after birth.

“There are (people) who say you should not implant congenitally deaf children. Some people say they don’t do as well,” Tonokawa says. “But I’m finding that’s not true. I think it takes them longer to get there, but they don’t have a history of hearing. It makes sense that those kids take longer to develop.”

The decision to recommend the implant for congenitally deaf children has been criticized by some members of the deaf community. They have argued that the implant might confuse children, leaving them to straddle hearing and deaf environments, Tonokawa says.

“Before, the feeling in the deaf education field and among some pediatric ear, nose and throat (physicians) was against implants. I think we’ve won them over by explaining that it’s just a tool,” she says.

“The people who are still very negative are within the deaf community. Their argument is ‘you’re fine as a deaf person and you’re part of a deaf culture and there is no reason to deny your deafness.’ ”

But Charles Estes, executive director of the National Assn. of the Deaf, says he fears that not enough is known about long-term effects of the implant, particularly electrical stimulation in the inner ear, a concern the FDA has also identified as needing further research.

“I, personally, think that the medical profession should do a lot more public education; make very, very sure that a candidate for an implant understands what to expect before they submit to this kind of surgery,” Estes says. “I know a growing number of deaf adults who have had the implant, and every last one of them, bar none, has eventually reached the point where they admit to themselves that it is not what it was cracked up to be. And they just discard the damn thing.”

Officials of Cochlear Corp., the U.S. subsidiary of the Australian-based manufacturer of the implant, have no information on long-term use. But many experts admit that patients of any age must make a concerted effort to master the implant or it will be a disappointment.

“One must be committed to relearning how to listen once they receive the implant,” says Jean Lombard, a spokeswoman for Cochlear Corp. in Englewood, Colo. “They give up because it’s hard. You might be set in your ways. If you were heavily reliant on sign language and you feel you get around and you’re not missing anything, then the implant is work.”

Tonokawa agrees that the right attitude makes a big difference in successful use of the implant. Teen-agers who have been deaf for a long time often make poor candidates, she says.

Likewise, parents who have neither the time nor financial resources to work with their child may find the implant a waste of money.

But, she says, children who learn to make the most of the implant have the enviable ability to feel comfortable in both hearing and deaf environments.

“My argument is not that we’re stealing them from the deaf culture, but we’re giving them a choice,” Tonokawa says. “It’s a tool to give children choices as adults. We’re not trying to change them or say deafness is bad.”

How The Cochlear Implant Works 1. Microphone recives sound 2. Sound sent to speech processor 3. Speech processor filters and codes sound 4. Code sent to transmitter 5. Code crosses skin into receiver 6. Receiver-stimulator converts code to electrical signals 7. Electrodes stimulate hearing nerves in inner ear Transmitter: magnetically held in place over the internal receiver-stimulator Cochlear implant: see detail below Directional microphone: fits behind the ear Cochlear Implant Reciver stimulator Magnet: holds external transmitter in place Electrode array: Tube with 22 electrode bands which stimulate hearing nerves inside the cochlea, producing sensation of sound Source: Cochlear Corp.