A cochlear implant is an electronic device that stimulates residual nerve fibers in the inner ear. These electrical pulses are sent to the brain and interpreted as sound. An implant system consists of an external speech processor and headset (located entirely behind the ear) and an internal, surgically implanted electrode array. We provide several types of cochlear implants, depending on a patient’s need. All of the devices we use are multi-channel cochlear implant systems, and all provide multiple speech perception strategies and other features.
If you have profound hearing loss, a cochlear implant may restore useful hearing and provide improved communication abilities. In choosing a cochlear implant program, the annual surgical volume is key, especially if there is an abnormality with the inner ear. The University of Michigan Cochlear Implant Program was established in 1984, and is one of the oldest programs in the country. We have restored hearing to more than 2,000 children and adults.
While hearing aids and other assistive listening devices simply amplify sounds, a cochlear implant transforms speech and other sounds into electrical energy that is used to stimulate surviving auditory nerve fibers in the inner ear. Unlike most hearing aids, cochlear implants have both internal (inside the skull) and external (worn outside the body) components. A surgical procedure is needed to place the internal processor component of the implant.
Candidates for cochlear implants should have:
- Severe to profound sensorineural hearing loss in both ears
- Little or no benefit from hearing aids, following an adequate period of training and experience with their use
- Evidence of a functioning auditory nerve
- The ability to provide a conditioned response to auditory or vibrotactile (detect sound through touch) stimuli
- Family stability and support
- Motivation and willingness to learn to use the implant
- An educational/rehabilitation program that emphasizes auditory skill development
- No other medical issues that would prevent surgery
We provide comprehensive testing performed by audiologists and speech-language pathologists to evaluate candidacy for a cochlear implant. Testing for candidacy includes a standard hearing test, and a speech recognition test administered while wearing appropriate hearing aids, to determine percentage of words recognized in sentences. A CT scan is also generally ordered.
Surgery for a cochlear implant is almost always done on an outpatient basis, with only a small incision hidden behind the ear. Extensive shaving of the hair is not required. A 4- to 6-week period is required to allow adequate healing of the incision site, and then the implant can be hooked up to the processor and turned on. During the activation, the device is adjusted and tuned using a computer. The patient then returns one week later for further programming to monitor any changes in hearing. Monthly visits to the implant center for programming may be necessary until your hearing stabilizes.
We also offer revision implant surgery for patients who’ve had cochlear implant surgery at another hospital that has failed.
We participate in clinical trials to evaluate new devices, and our program is part of the federally funded Childhood Development after Cochlear Implant (CDACI) study, aimed at defining variables that contribute to successful performance with a cochlear implant.