| A cochlear implant is an electronic device that is surgically placed behind the ear. It converts acoustic sound waves into weak electrical currents, which are then transmitted to the immediate area of the auditory nerve in the cochlea, or inner ear. Stimulated by these currents, the nerve then delivers impulses to the brain, where they are interpreted as sound. The implant, although not restoring or creating normal hearing, can help individuals who are profoundly deaf or severely hard of hearing have an awareness of sound.
Besides the implant, which is surgically placed, the device has external components. A small microphone is worn behind the ear that detects sound from the speech processor, which is usually worn in a pocket. The processor picks up sounds and transmits them into electrical impulses that travel up a small cable. These impulses are then delivered to the implanted electrodes in the cochlea.
A cochlear implant is very different from a hearing aid and is only recommended for individuals who have not had success with a hearing aid. Unlike hearing aids, which amplify sound, cochlear implants compensate for damaged or nonworking parts of the inner ear. Hearing through an implant may not sound the same as normal hearing, but it will enable many individuals to communicate orally, both in person and on the phone. |
Source: Medical Disability Advisor
| Severe deafness or profound hardness of hearing is the reason for the use of a cochlear implant. Individuals who have not benefited from a hearing aid are the main candidates for this device. |
Source: Medical Disability Advisor
| Cochlear implant surgery is performed under a general anesthetic in a sterile operating environment. It may be done either as an outpatient procedure or in hospital.
An incision is made behind and slightly above the ear. The skin flap is laid back to expose the underlying tissue and bone. A burr-type instrument is used to drill a circular hole in the bone for preparation for implanting the internal coil. The mastoid bone in the ear is opened to allow for placement of electrodes that will lead from the internal coil into the inner ear. The internal coil is then positioned in the prepared site and secured with stitches. The electrodes are inserted deep in the inner ear into the cochlea, which is the organ that transforms sound vibrations into nerve impulses for transmission to the brain. The incision is then closed and bandaged.
Once the surgical wound has healed, an external unit consisting of a stimulator with built-in microphone is provided for wearing behind the ear. It may be attached to eyeglasses, a headband, or special magnets between the internal and external components. |
Source: Medical Disability Advisor
| Auditory performance with a cochlear implant varies among individuals because of factors such as the duration of deafness, the mental abilities and motivation of the individual, the individual’s age at the time of hearing loss and at the time of cochlear implantation, and the acquired language skills before hearing loss occurred. Auditory results are not affected by the reason for the hearing loss.
The individual should expect complete healing without complications. Stitches will be removed a few days after surgery, and one or more follow-up visits to the implant facility will be needed to program the device. Because a cochlear implant improves hearing but does not restore normal hearing, the individual should be psychologically prepared to continue learning permanently. |
Source: Medical Disability Advisor
| Major complications that require additional surgery include flap problems, device migration or extrusion, and device failure. In rare cases, the facial nerve on the side of the operation may be damaged, cerebrospinal fluid may leak out, and/or the individual may experience vertigo. No deaths have been attributed to cochlear implantation. Surgical wound infection and bleeding may also occur.
Minor complications that are resolved without surgical intervention include unwanted facial nerve stimulation with electrode activation, which is readily rectified by device reprogramming.
Long-term complications of implantation relate to flap breakdown, electrode migration, and receiver/stimulator migration. |
Source: Medical Disability Advisor
| There are no special accommodations required for the individual who returns to his or her normal occupation and work. However, should the individual change jobs, the employer may need to provide listening and hearing assistive devices for use by the individual. Such devices may include special telephones and access to relay services, amplifiers, and signal lights.
Speech pathology programs and training will be needed for several weeks to introduce or reintroduce the individual to the hearing world. Continuous practice at identifying sounds and voices is needed. |
Source: Medical Disability Advisor
| "Cochlear Implants." American Academy of Otolaryngology - Head and Neck Surgery (AAO-HNS). 2002. 19 May 2005 <http://www.entnet.org/healthinfo/ears/cochlear-implant.cfm>. "Cochlear Implants." National Institute on Deafness and Other Communication Disorders. 23 Feb. 2005. National Institutes of Health (NIH). 19 May 2005 <http://www.nidcd.nih.gov/health/hearing/coch.asp>. "What is a Cochlear Implant?" British Cochlear Implant Group. 19 May 2005 <http://www.bcig.org/professional/allprofs_faqa.htm>. |
Source: Medical Disability Advisor