Cochlear Implants
What is a Cochlear Implant?
Who is a Candidate?
Factors Related to Successful Use
What is Involved?
What Can Be Expected?
Other Benefits Sometimes Reported:
Where Can I Get More Information?
What is a Cochlear Implant?
The cochlear implant is a prosthetic replacement for the inner ear (cochlea). The cochlear implant is very useful for people who receive minimal or no benefit from a conventional hearing aid. The implant is not a hearing aid. It is a neural prosthesis.
The cochlear implant bypasses damaged parts of the inner ear and electronically stimulates the nerve of hearing. Part of the device is surgically implanted in the skull behind the ear and tiny wires are inserted into the cochlea. The other part of the device is external and has a microphone, a speech processor (that converts sound into electrical impulses), and connecting cables. It is battery powered, adjustable, and expensive.
Cochlear implants have been performed for over 25 years and have become the standard treatment for people with profound hearing loss, who desire to use spoken language. Today, over 100,000 adults and children worldwide have received a cochlear implant.
The American Medical Association and the American Academy of Otolaryngology - Head & Neck Surgery have approved the use of this medical procedure for adults and children over the age of 12 months.
Cochlear implants are very sophisticated devices. The multichannel implant stimulates the hearing nerve in a variety of places to give information about pitch, which is essential for understanding speech. The externally worn processor is designed to incorporate advances in technology, so there is no need to wait for next year's upgrade. The sooner the person receives the implant after becoming deaf the better he/she will do with the implant. Ear-level processors are now available for all cochlear implants.
Who is a Candidate?
Candidates for implants are adults or children (12 months or older) with all of the following:
Profound or severe hearing loss in both ears (this includes people with "nerve" deafness)
Receive little or no benefit from hearing aid in understanding speech by listening alone
Receive little or no benefit from hearing aid in understanding speech by listening alone
No medical reason to avoid surgery
A desire to interact with the hearing world and to communicate with spoken language
Realistic expectations about results
Factors Related to Successful Use
Functioning auditory nerve
For adult: Good speech, language, and communication skills
Good motivation
Short amount of time without hearing sound
Support from family and friends
For children: auditory training and oral education are essential for maximum success
What is Involved?
A. Evaluation:
Evaluation procedures used to determine whether an individual is an appropriate candidate include:
Ear examination to determine cause of hearing loss and absence of infection
Medical examination for eligibility for surgery and anesthesia
Hearing ability testing, with and without best-fit hearing aid
Evaluation of communication skills
CT scan to determine patency of the inner ear (cochlea)
Optional Tests
Psychological evaluation to assess motivation and expectations
Testing can be discontinued at any point if the candidate and/or evaluation team feels it is not appropriate to continue.
B. Review:
Results of tests are reviewed by the cochlear implant team before a decision is made on whether to implant. Parents are considered an integral part of their child's
Implantation is recommended only for people we believe will benefit from an implant.
Pre-authorization for implantation from the third party payor is requested. Often several weeks are required for authorization and scheduling.
C. Surgery:
The surgical risks are the same as for any other ear surgery and are considered minimal. The surgery takes approximately 1-1/2 hours, and the hospital stay is usually 1 day for adults and 1 or 2 days for children. Selected patients may be done as day surgery cases.
D. Fitting:
In adults, the headset and speech processor are fitted 4 weeks after surgery. The audiologist obtains soft and comfortable listening levels for each of the electrodes and uses this information to create a MAP or program. The fitting is done over several days.
In children, the fitting procedure continues over a 3-month period. Young children are typically seen 2 to 3 times a week for the first month and 1 or 2 times a week for the next 2 months to obtain a stable MAP.
Hearing speech for the first time with the implant may sound unnatural during the fitting but over many days to weeks it begins to sound familiar. People who have never heard before require longer times to adjust to the new sounds. For adults who have heard speech before, the MAP is put onto the speech processor and is adjusted as necessary to custom fit the individual.
For children who have never had hearing, the initial reaction to sound varies. Some children do not respond to sound at first. Other children may show surprise, fear, inquisitiveness, or happiness. Dramatic changes in auditory and speech skills are typically not observed initially. Performance usually continues to improve over time with auditory and speech training. Early implantation gives the greatest opportunity for normal development of speech and language skills.
Electrodes are checked and adjusted, and instructions in use and care of the implant are given.
What Can Be Expected?
Adults hear medium level and even soft sounds and can differentiate among many environmental sounds.
It is important for children to receive auditory and speech training to maximally benefit from a cochlear implant. A child's performance will usually continue to improve over an extended period of time with training.
Understanding speech in combination with speech-reading (lipreading) improves. Speech-reading becomes less stressful and more accurate.
Speech understanding ability increases over time with continued treatment and experience.
Most people who had normal hearing at one time are able to understand some speech without speech-reading. The degree to which they are able to do this depends, in part, on the success factors mentioned earlier.
Understanding speech over the telephone varies greatly. Most people are able to carry on conversations, while others have difficulties.
Most people experience a positive effect on their feelings of involvement in daily life, self-worth, and relationships with family, friends, and co-workers.
Most people experience an improved ability to monitor the quality and volume of their own voice.
Adults who lost their hearing completely as children may not understand speech without speech-reading, but experience all the other benefits and may be able to tell the difference between some speech sounds. They often feel more connected to the world around them because of the sounds they now hear.
Performance and benefits vary from individual to individual and it is not possible to predict how much benefit any one person will obtain. The choice of which device to use is less important than the other success factors listed above. Patients with favorable success factors are likely to do well with any implant and it is not possible to predict outcome.
We encourage open dialogue with our team members to answer questions and discuss possibilities. We expect to provide care for our patients throughout their lifetime and we are prepared to make a long-term commitment to their well-being.
Other Benefits Sometimes Reported:
Richer relationships with family and friends
Increased confidence and ease of communication
More social opportunities
Improved occupational performance or opportunities
Music appreciation is noted by some users
Where Can I Get More Information?
For more information about cochlear implants for ADULTS call the
University of Washington Medical Center
Tina Worman, MS
206-598-4022
For more information about cochlear implants for CHILDREN call
Children's Hospital and Medical Center:
Susan J. Norton, PhD
206-528-2712
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