|
|
|
Cochlear ImplantationFor
many patients amplification is all that is necessary.
For others, the hearing may be so poor that amplification is not
adequate. Unfortunately, once the
hearing nerve is permanently damaged, no magic potion or medication can bring
the hair cells back to life. Until
recently, there was nothing to do beyond conventional hearing aids.
Now, there is something else to be done.
One of the most exciting advances in Neurotology has been the invention
of the cochlear implant. This
amazing device is able to transform a person who was totally deaf to one who can
converse on the telephone. The cochlear implant is not a hearing aid. It is a surgically implantable device that stimulates the cochlear nerve directly, bypassing the dead hair cells. The cochlear implant system consists of two separate parts. The external device collects sound and transforms it into electromagnetic waves. The internal device receives these electromagnetic waves and transforms them into electrical impulses are carried by an electrode to the cochlear nerve. Stimulation of the cochlear nerve is interpreted by the brain as sound.
Implantation
requires a moderately complex three hours surgical approach.
An incision is made behind the ear.
The mastoid is opened to expose the cochlea.
The ICS (electronic receiver package) is embedded in a pocket just above
the mastoid and then the electrode is inserted into the cochlea.
Surgery is done under general anesthesia and there is usually not much
postoperative pain. Recovery occurs
over the course of several days. Complications
are rare. The
incisions are allowed to heal for about four to six weeks prior to any attempts
to stimulate the nerve. At that
time, the external processor is then placed over the ICS electronic receiver
package and transmissions of sounds can begin.
It
is important to realize that the surgical aspect of implantation is actually the
easy part of the hearing restoration process.
Extensive audiologic programming sessions are required to fine-tune the
sounds so that they are appropriate and true to life.
The audiologist is responsible for programming the device to transmit at
the proper volume and clarity. Manipulation
of the electrical impulses may help eliminate distortion.
Adjustments may be required on a periodic basis. The
cochlear implant is not for everyone. It
is usually reserved for people who have profound hearing loss who cannot benefit
from conventional hearing aids. If
they have residual natural hearing, there is a risk that placing the electrode
into the cochlea may destroy all remaining hair cells. Candidates should be
older than two years of age and the healthy enough to undergo surgery.
(Audiogram Criterion) Cost effectiveness: Although cochlear implantation is very expensive, the procedure is usually covered by insurance (where as hearing aids are typically not covered by insurance). Moreover, many studies have been done to evaluate cochlear implantation's cost effectiveness and have found it worthwhile. The benefits of cochlear implantation are obvious. When one is able to make a deaf person hear, you can increase productivity, decrease dependency and improve quality of life. There is the possibility of avoiding certain life-threatening situations (by allowing a person to hear the honking of a car for instance). Since hearing is required to develop speech, it helps preserve speech function in deaf adults and allows this development of speech in young children. |
|
Questions or problems regarding this web site should be directed to Dr-Li@Dr-Li.net.
|
