Triad Hitchup

Monday, May 21, 2007

Article on combined CI and HA technology

Published: May 17, 2007 12:30 AM
Modified: May 17, 2007 06:56 AM
1-2 punch could help hearing-impaired
Jean P. Fisher, Staff Writer
James A. King has always had poor hearing, but now it's so bad the Warren County pharmacist often can't understand patients at his store counter, waiters in restaurants or the high-pitched voices of his six grandchildren -- even with the help of hearing aids.
King, 64, hopes an innovative surgery he recently underwent at UNC Hospitals in Chapel Hill will change all that.

Last month, a surgeon implanted a small device above King's ear that will directly stimulate nerves involved in hearing. The device, called a cochlear implant, will work in tandem with a special hearing aid to help him hear a more complete range of sounds. King is among the first patients in the country to receive the combination treatment, which is being tested at UNC-Chapel Hill and elsewhere as part of a national clinical trial sponsored by Med-El, the Austrian company that makes the technology.

The dual device is aimed at people who, like King, hear too well for a cochlear implant alone but not well enough for hearing aids to be effective. It's hard to say how many patients might be candidates for the combination treatment. But hearing loss is highly prevalent, affecting about 28 million Americans of all ages. About 17 out of every 1,000 children younger than 18 experience hearing loss, according to the National Institute on Deafness and other Communication Disorders. After age 65, the rate jumps to 314 out of every 1,000 people.

"Have you seen a child on his first Christmas morning?" said King, describing his delight at being included in the trial. "This is a chance for me to really enter life again. Right now, I'm horrified to even answer the phone. It's embarrassing."

An innovation that was first approved for use in the United States in 1984, a cochlear implant has a microphone that picks up environmental sound and a speech processor that interprets it. It also includes a transmitter and receiver that collect signals from the speech processor and convert them into electric impulses, which are then routed via implanted electrodes to different regions of the patient's auditory nerves. The device can be placed in a short surgery, with no need for overnight hospitalization.

Full cochlear implants, used without hearing aids, provide hearing to patients who are profoundly deaf or nearly so. The implants, approved for use in patients as young as 1 year old, don't enable normal hearing but can make it possible for the deaf to hear a representation of sounds in their environment. With practice, many can learn to understand speech. The surgery, including the device, can be upwards of $40,000, though health insurance often covers the cost.

Most people with milder hearing loss, however, can't benefit from a cochlear implant. That's because their residual hearing is still better than the approximated sound provided by the device. So instead, more mildly impaired patients use hearing aids, which help by amplifying sounds.

Dr. Craig Buchman, the UNC-Chapel Hill ear surgeon who did King's surgery, said the combined implant and hearing aid system may become a new treatment option for patients like King who aren't candidates for full cochlear implants.

The dual device, called the electro-acoustic system or EAS, aims to solve such patients' hearing problems by using the partial implant to restore middle- to high-pitched sounds, which most patients with severe hearing loss can't pick up. Then, a specially designed hearing aid joins in to amplify the lower-pitched sounds patients can detect. It's already available to patients in Europe, but it is still considered investigational in the United States. Results from the clinical trial could pave the way for approval of the dual system in this country.

"You're actually adding the portion of hearing that they're missing to the portion that they do have," Buchman said.

Buchman said most people with age-related hearing loss would likely not be impaired enough to be candidates for the EAS procedure. Patients with severe enough hearing loss to qualify generally have a history of infections, exposure to certain antibiotics or hereditary factors that contribute to impairment.

James King, who has battled hearing impairment since childhood, doesn't yet know how much his partial implant will help. He is still healing from surgery and expects to return to UNC-CH later this month to have his device activated. According to his doctors, it may be up to six months before King adjusts to the system and begins to notice improvement.

"I'm hoping that I'm going to be able to communicate with people again," he said. "I don't really know what to expect, but I think it's going to be great."


Staff writer Jean P. Fisher can be reached at 829-4753 or jean.fisher@newsobserver.com
 

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