Cochlear Implants
Cochlear implants are electronic devices designed to improve speech understanding and environmental awareness of sounds for individuals with severe to profound hearing loss and very poor speech understanding. Part of the device is implanted under the skin behind the ear, bypassing damaged hair cells in the cochlea to stimulate the hearing nerve directly.
The device has both external and internal components. The external portion includes a microphone, transmitter and a speech processor computer chip. The external components attach to a cable and a magnet that holds the device to the head and communicates with the internal implant. The external processor may be worn behind the ear or clipped to a shirt with a long cable. The internal portion is comprised of an electrode array, internal receiver antenna and processor; these components are implanted surgically.
Some external processors look similar to hearing aids, but the method of transmitting sound information to the hearing nerve is different than traditional amplification. The microphone on the external processor picks up sound in the environment and sends the information to the speech processor. The speech processor converts the acoustic signal to a digital signal and sends the information to the receiver in the internal implant. Depending on the information relayed, the internal implant will stimulate specific electrodes within the electrode array. This information is sent to the hearing nerve and allows the brain to detect sounds at different frequencies/pitches so that it may be perceived as sound and speech information. This process is completed very quickly, many times per second.
Cochlear implantation is a surgical option for those who find little or no benefit from hearing aids. Potential candidates are evaluated through a battery of tests, including a hearing evaluation, vestibular evaluation, review of medical history, physical and a CT scan or MRI study. Overall physical and emotional health, duration of significant hearing loss, consistent use of hearing aids, motivation to proceed with a cochlear implant surgery, realistic expectations for outcomes and family support are all components that factor into evaluating if cochlear implant surgery is an appropriate choice for a patient and their family.
After the device is implanted, cochlear implant recipients will be scheduled for a series of follow-up visits, including evaluation with the physician, audiologists and speech language pathologists. During the first year, cochlear implant recipients will have more appointments and follow-up visits to ensure that they are adjusting to the cochlear implant. After the first year, the follow-up visits will be tailored to meet individual patient needs, which are determined by the age of the patient and clinician and physician assessment of specific outcomes.
