BC Adult Cochlear Implant Program

Testing will typically occur over a couple days at the Cochlear Implant Clinic.  We encourage you to bring a family member or friend for support.

Please bring your hearing aids to your assessment.  Be sure that they are working and have been set appropriately for your hearing loss.

There are several steps to the cochlear implant candidacy assessment.  Your audiologist will let you know which tests  you need to complete.

Day 1

• Complete hearing test: determines the type (conductive, sensorineural, or mixed) and degree (mild to profound) of hearing loss you have.
  • Pure tone air and bone conduction threshold testing: tests the type and severity of hearing loss.
  • Tympanometry: tests the mobility of the eardrum and middle ear bones.
  • Acoustic reflex testing: tests the function of the middle ear.
  • Otoacoustic emissions: tests the function of the sensory hair cells in the inner ear.
• Speech testing: tests how well you can understand speech. You will listen and repeat back a series of words and sentences presented at a loud but tolerable volume.
• Vestibular testing: tests the function of the vestibular end organs in your inner ears.
• Real Ear Measurements:  your audiologist will verify if your hearing aids are fit optimally based on your current hearing test.  If your hearing aids do not meet prescriptive targets, then clinic hearing aids will be programmed for you, ensuring you have access to optimally fit hearing aids for your CI candidacy assessment. 

Day 2

• CI candidacy assessment:   Your audiologist will ask you many questions to understand your hearing and ear related history. They will test your ability to understand words and sentences using the optimally fit hearing aids. After all testing has been completed, your audiologist will advise you if you are a CI candidate or not.  If you are deemed an audiological CI candidate, you will learn in detail about cochlear implants (what to expect, benefits and limitations, future costs, etc).  If you are not yet a candidate for a cochlear implant, they will provide tips to help with your hearing loss.

The following tests may be performed, if required:

• Auditory brainstem response testing. This test checks the function of your hearing nerve.  

• Slow cortical potential testing.  This test checks your brain's ability to process auditory information.  

Testing is thorough and can take several hours. You will take breaks during the day, including one for lunch.

After you have been determined to be a CI candidate, you will also meet with the:

• Social worker, who will learn about how your hearing loss affects you and those around you. They will share helpful resources to give you the best possible chance to successfully use your CI.
• ENT surgeon, who will verify that you are medically and surgically able to receive the cochlear implant surgery. 

Your audiologist will spend time with you reviewing your test results.  Usually we are able to tell you at the end of your assessment if you are an audiological candidate for the cochlear implant. Occasionally, usually due to problems with poorly fit hearing aids or if we are not able to complete all the testing required, you may be asked to come back for further testing.

You will still need to be assessed by one of the surgeons to complete the medical/surgical candidacy assessment. If your initial referral to the cochlear implant clinic was from an audiologist or hearing instrument provider, you will be required to have your family doctor send a referral for you to the surgeons.

• If you are not yet an audiological candidate for the cochlear implant, your audiologist will offer a number of recommendations that will help address some of the difficulties you have with your hearing.
• If you are an audiological and medical candidate for the cochlear implant your name will be placed on the cochlear implant surgical waitlist.

We expect that you and your family will have many questions. Your audiologist will be happy to answer any questions or concerns you may have.

If you have any other health issues, you may need to go to the Pre-Admission Clinic at St. Paul’s Hospital before your surgery. This may involve a separate trip to Vancouver.

There is currently a waitlist for cochlear implant surgery. We are usually able to give two months' notice of the surgery date. If you are not able to take the surgery date we offer, we will give you the next available surgery date that works for you.

All adult cochlear implant surgeries are performed at St. Paul’s Hospital in Vancouver.

The surgery takes approximately two hours. It is performed under general anesthetic.

The surgeon will make an incision behind the ear. They may shave a small amount of hair around the incision. The surgeon will drill through the mastoid bone, a honeycomb of air cells behind your ear. This allows access to the area behind your eardrum through which the implant electrode is inserted into the cochlea, the organ of hearing.

The surgeon closes the incision using dissolvable sutures under the skin. This means there are no sutures to remove later. They will place a head dressing over the incision. You can remove the dressing at home the day after surgery.

After the surgery, we will monitor you in the recovery area until you are fully awake. In most cases, you are able to leave the hospital the same day. If you are feeling unwell, you may be required to stay one night in the hospital. If you live outside of the Lower Mainland, you should plan to stay in a hotel in Vancouver the night before and the night of the surgery. You may fly or drive home over mountain passes the day after the surgery. Otherwise, it is best to avoid flying for about two weeks after surgery. You will not be able to use a hearing aid in the operated ear for four weeks after surgery (if the residual hearing is preserved).

The risk of a serious complication occurring during general anesthetic is approximately one in 200,000 patients.

You may experience some numbness at the top of the ear that usually recovers over several months. It is rare for this numbness to be permanent.

The surgeon needs to drill beside a nerve that goes to the muscles of the face. If that nerve is damaged, you will have either a temporary or a permanent weakness (paralysis) of one side of your face. The risk of paralysis of your face is around one in 1000 patients (0.1 per cent).

There is a second nerve that supplies taste to one-half of your tongue. A temporary change in the sense of taste or a metallic taste is seen in 10 per cent of patients. Some complain about a permanent change in their taste, but this is extremely rare.

When the implant is inserted into the cochlea (inner ear), you will probably lose any natural hearing in that ear.

Dizziness is common for two or three days. Occasionally people can have dizziness for several weeks, but this is rare. If this occurs, you should call your surgeon.

There is a risk of an infection after the surgery, but it is less than one per cent. If an infection occurs, the implant may need to be removed.

If an infection occurs, there is also a risk of meningitis, an infection of the brain. The risk of meningitis immediately after surgery is one in 5,000. The risk of meningitis once everything has healed is about the same as for the general population. To lower the risk of meningitis, we'll provide information on vaccinations. We recommend discussing this information with your primary care provider.

During your switch-on appointments, you will work with your audiologist to create a MAP. A MAP consists of a variety of parameters that control how your cochlear implant will electrically stimulate the hearing nerve. This is what allows you to hear. Your MAP is unique to you.

Once we have created your MAP, the audiologist will activate your speech processor. This allows you to hear with your cochlear implant for the first time.

Patients often report hearing with the cochlear implant for the first time is confusing. Since hearing with the cochlear implant is different from normal hearing or hearing with hearing aids, patients often report they can hear sounds, but are unable to understand what those sounds are or mean. The process of learning to attach the appropriate meaning to the sounds from the cochlear implant takes time and practice. Some patients accomplish this somewhat quickly, others take much longer. How much you understand initially does not predict how you will do later on. The more auditory training or listening practice each recipient commits to, the better they will hear.

In addition to creating MAPs, your audiologist will work with you to teach you how to practice listening so that you can continue to practice when you return home. Your audiologist will also spend time with you reviewing your equipment to be sure you are familiar with how to use it. You will also complete a series of baseline tests. These tests will be repeated at each subsequent appointment so that your performance with your cochlear implant can be monitored.