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Cochlear
implants seem to be getting more popular.
About 100,000
people worldwide have cochlear implants, 45,000 of which live in the
U.S. The demand for cochlear implants is increasing annually by 12 to
14 percent, according to the American Speech Language and Hearing
Association.
Moreover, each
cochlear implant in a child saves taxpayers about $53,198, and up to
$420,000 can be saved in special education costs if a deaf children
receives early intervention, based on statistics from the National
Institute on Deafness and Other Communications Disorders.
"If I had a
baby born deaf today I would get him cochlear implants," said Oliveri,
who raised four sons, ages 13, 15, 17, and 20, while deaf.
Oliveri
believes her hearing was destroyed when she was a baby. She was
hospitalized with a "strep throat." Between a high fever and
antibiotics, her cochlea were damaged.
"The basic way
we hear is that sound vibrates our ear drums, and the small hearing
bones transfer the vibrations to the inner ear," said her surgeon, Dr.
John F. Kveton, clinical assistant professor of otolaryngology at the
Yale School of Medicine.
The stapes
bone, in turn, sends vibrations into the cochlea. The cochlea, from the
Greek word for "snail," is a small curved organ filled with endolymph
fluid. Sound waves cause the fluid to vibrate. The cochlea is lined
with about 16,000 hair-like nerve receptors that wave as the fluid
moves back and forth.
The receptor
signals feed into the auditory nerve and to the brain.
Oliveri felt vibration through the floor and the draft from opening
doors and little else. Children were not screened for deafness then and
her condition did not become apparent until she was 2.
"I wasn’t talking and my brother, who is 14 months younger, was."
Her parents did not take doctors’ advice to send her to a deaf school
where she could learn to sign.
Instead she got two hearing aids. They amplified the 2 percent of
hearing she had left, mostly in the low frequencies.
Oliveri said she is grateful to her mother and father, who taught her
to use the combination of lip reading and hearing aids to communicate.
"Lip reading is a gift. You have to re-wire your brain to be visual.
Auditory is turned into visual," she said.
Friendly teachers sat her in the front row so she could see their lips.
She loved to read and did well in all subjects except French. Lip
reading does not convey an accent very well.
In college she was on the tennis team, taught skiing and was an avid
hiker. She did not do much drinking. "If you’re seeing double it’s hard
to lip-read," she said.
College professors in Vermont were sometimes difficult to understand
under prolific facial hair. It’s also difficult to lip-read and take
notes simultaneously.
"I grew up wanting to be a veterinarian, but I wasn’t good at math or
science. They’re more abstract, not like English. Girls weren’t
encouraged to go into the sciences, either," she said.
After graduating in 1978, she bummed around in Utah, teaching skiing to
special needs children using sign language. She met her future husband
there, who suggested that the couple "move east and get real jobs."
"Law school seemed like a good choice. There are many different ways of
practicing," she said.
After obtaining her degree in 1984, she took the bar exam in New Haven.
Construction near the test room distracted others. All she felt were
vibrations.
Oliveri then practiced tax, health and environmental law in an
administrative capacity in then-Attorney General Joseph I. Lieberman’s
office.
Her children quickly discovered that she could only "hear" them if she
was looking at their faces. Tiny hands would gently grab the sides of
her head and direct her vision.
She started to think seriously about a cochlear implant after her
youngest son started school.
"I had qualms. Most people with implants had normal hearing most of
their lives. Auditory pathways in their brains were well developed,"
she said.
Oliveri understood that she would need to build these pathways as an
adult. "It wouldn’t be a hearing issue, it would be a brain issue," she
said.
After she turned 40 and started to become farsighted she decided it was
time for a cochlear implant.
"A cochlear implant bypasses the damaged sensory cells to restore
hearing to the patient," said Patricia Trautwein, director of education
with Advanced Bionics of Boston, a manufacturer of implant components.
"It’s a very tiny, sophisticated, computer. A microphone picks up sound
and processes it into digital code and then broadcasts it to the
implant," she said.
Like any computer, the cochlear implant’s software can be updated, she
said. Cochlear devices are designed to accommodate new hardware and
software.
The current generation of implants has 120 channels, or bands, or
resolution, Trautwein said.
The actual implant is about 1 inch long and one-twenty-fifth of an inch
thick. Babies are born with full-sized cochlea, so a child’s implant
does not need to replaced as the skull grows.
The processor, which fits behind the ear, powers the inner workings by
inducing electricity magnetically, Trautwein said.
Kveton said that after openings are made in the mastoid bone and
cochlea, the curved electrode is gently inserted until it lies over the
appropriate receptors. Signals emerge from the implant at points in the
cochlea that normally would respond. For example, high-pitched signals
are emitted at the high-pitch region of the cochlea.
Since some of the cochlear receptors are still active, and some more so
than others, the output of the implant must be adjusted accordingly.
This "mapping" is performed about a month after the implant.
The earlier a profoundly deaf child receives implants, the more easily
the child will learn to speak. If implants are installed by 12 months
of age, talking and language are very close to normal, he said.
The device, surgery and the hospital stay generally costs about $60,000
to $70,000, Kveton said.
Medicare reimbursements barely cover the cost of the implant, meaning
that hospitals lose money.
"This will probably become a big issue. There will be more demand as
the population ages and hospitals won’t do them anymore," he said.
Oliveri felt lopsided with one implant, and she could not localize
sounds. So in 2004 she received another implant.
"I really missed having two ears and sound on both sides of my head. A
few people are getting two," she said.
Insurance paid for the surgeries. "With two implants the sum of the
whole is greater than the parts," she said.
"I love hearing the birds sing, and the wind in the trees," Oliveri
said. "I can hear emotions in people’s voices."
Author:
http://www.nhregister.com/site/news.cfm?newsid=
18094294&BRD=1281&PAG=461&dept_id=31007&rfi=6
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