About cochlear implants

What is a cochlear implant?

illustration of cochlear implant and inner earA cochlear implant is an electronic medical device for individuals with moderate to profound hearing loss that is designed to restore the ability to perceive sounds and understand speech. Unlike a hearing aid, which amplifies sound picked up acoustically, a cochlear implant bypasses the damaged hair cells in the cochlea and stimulates the auditory nerve using electrical current. (Illustration credit: The National Institute on Deafness and Other Communication Disorders)

A cochlear implant consists of both external and internal components.

The external components:

  • A speech processor with a microphone that picks up sounds from the environment
  • The processor analyzes sound signals, digitizes them, and sends them to a transmitter that is worn on the head
  • The transmitter sends the signal to the surgically implanted internal components

The internal components:

  • A receiver/stimulator which is placed under the skin near the ear receives signals from the transmitter and converts them into an electrical signal and sends the information to an electrode array
  • The electrode array is placed into the cochlea and stimulates the auditory nerve which then sends information to the brain, which is interpreted as sound

Who is a candidate for a cochlear implant?

  • Children who are 12 months (younger in some cases) to 18 years of age and adults of any age
  • Adults and children with severe to profound sensorineural hearing loss in both ears
  • Individuals who receive limited benefit from appropriately fitted bilateral hearing aids
  • Individuals and families with appropriate expectations and an understanding of the necessary follow-up

Who is a candidate for a hybrid cochlear implant?

  • Adults aged 18 years and older
  • Individuals with residual low frequency hearing sensitivity and severe to profound high-frequency sensorineural hearing loss in the ear to be implanted
  • Individuals who obtain limited benefit from appropriately fitted bilateral hearing aids
  • Individuals with no contraindicating medical condition (determined by the physician)

What happens at the initial cochlear implant evaluation?

Below is an outline of what patients can expect at their initial cochlear implant evaluation. The initial evaluation is a cooperative process that involves many professionals. Patients should expect a full day of diagnostic testing and counseling.


A complete diagnostic audiological evaluation will be completed to determine the type and degree of hearing loss.

Hearing aid verification

Verifying that the hearing aid is appropriately fitted for your hearing loss is an important component of the cochlear implant evaluation. An audiologist will make sure that the amount of amplification that your hearing aid is providing matches prescribed gain in the verification computer software. You will be tested with the hearing aid(s) you are currently wearing. If you do not currently wear hearing aids, or your hearing aids are not appropriately fitted, you will be temporarily fit with hearing aids just for the duration of this test. It is important that you bring your own hearing aids and ear molds to this evaluation even if you have not been wearing them. If you have never worn hearing aids, you might be required to undergo a hearing aid trial before proceeding with a cochlear implant evaluation.

Examination by an implant audiologist

Aided speech perception testing will be administered to determine if you are audiologically an implant candidate. The audiologist will discuss the cochlear implant in detail and review what patients gain from its use. Pediatric patients will be evaluated audiologically and by caregiver report.

Examination by an otologist (ear doctor)

The otologist will examine you to determine if you are medically an implant candidate. The otologist will also review the imaging results and make a recommendation regarding implantation. The otologist will also answer any further questions you may have regarding the surgery.


To determine if the anatomy of your inner ear is adequate for placing a cochlear implant, you will have either a Computerized Tomography (CT) Scan or a Magnetic Resonance Imaging (MRI).  Contrast dye will not be used; therefore you can eat regular meals prior to this test.

What medical factors might exclude me from implantation?

Contraindications for cochlear implantation include deafness due to lesions of the acoustic nerve or central auditory pathway, active and present middle ear infections, absence of development of the cochlea or acoustic nerve, or health conditions that would not allow a candidate to undergo surgery.

What about my cochlear implant surgery?

The operation for a cochlear implant typically takes about 3-4 hours and is done under general anesthesia. Typically, patients check in on the day of surgery, stay overnight in the hospital, and are discharged the next day. The hair around the ear will be shaved, but grows back in its normal manner.

What happens after I receive a cochlear implant?

Three to four weeks after your cochlear implant surgery, your audiologist will activate your cochlear implant. This waiting period between surgery and activation provides time for the operative incision to heal completely. Your audiologist will give you your cochlear implant processor at the time of your initial activation.  Your audiologist will program your sound processor with programs that are specific to you.   Specifically, you will be asked to tell your audiologist about the loudness of the sounds and about the pitch of the sounds.  At this appointment, your audiologist will also give you information and show you how to properly care for your device. You will need to come back for several follow-up appointments so that your cochlear implant can be adjusted as you get more used to the sound. For an adult, you will be asked to come back at 2-weeks, 1-month, 3-months, 6-months, and annually following your cochlear implant activation.  You might be asked to come back more frequently during the first month following activation if you received a Hybrid cochlear implant so that we can monitor your hearing. For a pediatric patient, you will be asked to come back for follow-up appointments at 2-weeks, 1-month, 4-months, 8-months, and annually.  Interim appointments might also be needed. It is important that you wear your cochlear implant all waking hours of the day so that you receive the best benefit from your device.

How can I get a hold of my cochlear implant manufacturer?

Your cochlear implant manufacturer can be a great source of information. All of the cochlear implant companies provide 24-hour audiological support and assistance when troubleshooting your equipment. Please visit your cochlear implant manufacturer website to become familiar with the multitude of information that is available.

Last reviewed: 
October 2018

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