Cochlear Implants
In the case of profound deafness, almost all of the sensory cells are missing
or so severely damaged that sound cannot be converted into the electrical
impulses that ultimately generate the sensations of hearing, even with the
help of modern
digital hearing aids. The primary function of a cochlear implant is to convert
sound energy into low-level electrical currents that are used to stimulate
the auditory or hearing nerve directly, thus by-passing the damaged inner
ear or
cochlea.
Cochlear implants have become the medical treatment of choice
for those adults and children who, because of the severity of
their hearing impairment,
cannot
understand spoken language sufficiently through amplified residual hearing.
As noted in the 1995 National Institutes of Health Consensus Statement
on Cochlear
Implants in Adults and Children, the multi-channel cochlear implant has
become a widely accepted auditory prosthesis for both adults
and children. Almost
all individuals with this degree of hearing impairment have, in their hearing
nerve,
sufficient auditory nerve fibres that can be stimulated electrically.
- he/she
has a severe to profound hearing loss in both ears;
- he/she
cannot hear all speech sounds with
hearing aids, and/or hearing aids provide little or no benefit
despite consistent
use and appropriate
intervention; and
- medical testing confirms no barriers
to surgery.
There is no minimum age for referral for assessment for
a cochlear implant. |
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