Cochlear [KOK-lee-uhr] implants are a tiny electronic devices implanted in your child’s ears. They can help people who are deaf or very hard of hearing process sounds and speech.
Cochlear implants are different from hearing aids. Hearing aids make sounds louder. Cochlear implants work by sending electrical signals to the auditory (hearing) nerve – and to the brain. A cochlear implant has two parts:
- Microphone—which is worn outside of the body, usually behind the ear. This picks up sounds from the environment and sends them to the implant.
- Receiver and electrode—which are implanted inside the cochlea in the ear. These take signals from the microphone and change them into electrical signals. The signals are sent to the auditory (hearing) nerve and to the brain.
Hearing with cochlear implants is different from normal hearing. Learning to use them requires working with a therapist.
Cochlear implant surgery is the surgery that is used to put the cochlear implants in your child’s ear. This surgery can be recommended by an audiologist (hearing specialist), and is done by a surgeon who is experienced with installing these implants. Cochlear implant surgery should be considered after other treatments for hearing loss or deafness have been proven not to work.
Cochlear implant surgery may be an option for children who are:
- At least one year old.
- Deaf or almost deaf in both ears and unable to hear with hearing aids.
- Motivated to learn how to use the implants.
- Understand that implants do not restore normal hearing.
Like all surgeries, cochlear implant surgery has some risks. Talk about with your doctor and surgeon. Some of these risks can happen during the surgery, including:
- Anesthesia problems. Anesthesia [ann-ess-THEE-zha] is medicine that puts your child to sleep and makes them numb so that they aren’t awake and don’t feel any pain during the cochlear implant surgery.
- Bleeding and infection. Sometimes, the cut the surgeon makes to install the cochlear implant can get infected after surgery. Infection is rare but serious.
- Facial nerve injury. The nerve that controls the muscles in your child’s face goes through their ear. During surgery, this nerve can be injured, which can make your facial muscles weak or paralyzed.
- Bacterial meningitis [men-IN-jai-TIS]. This is an infection of the lining around your brain that is rare but very serious.
- Cerebrospinal [suh-REE-broh-SPY-nuhl] fluid leakage. The fluid surrounding the brain can leak out of the hole your surgeon makes to install the cochlear implant.
- Reparative granuloma [rih-PAIR-ih-tiv GRAHN-yoo-LOW-muh]. If your child’s body rejects the implant, the area around it can be inflamed and cause other symptoms or problems.
If the surgery is successful, there can also be risks from using the cochlear implant itself. These can include:
- Hearing sounds differently. The sound from a cochlear implant is different than normal hearing, and might seem mechanical or synthetic.
- Losing more hearing. The implant might destroy any hearing that was left in your child’s ear before the surgery.
- Inability to have some medical tests. Some tests and procedures, like MRI, neurostimulation [NOO-row-STIHM-yoo-LAY-shun], electrical surgery, or ionic radiation therapy, can damage the cochlear implant.
The main benefit of cochlear implant surgery is that it can make your child’s hearing better if they are severely or profoundly deaf. This surgery can help with:
- Hearing different sounds. A cochlear implant can let you tell apart sounds at different volumes, as well as different kinds of sounds.
- Talking. This implant can make it easier to understand what people are saying when they talk without needing to use lip-reading.
- Other Benefits. A cochlear implant might make it easier for your child to use the phone, watch TV, or even listen to music.
There are many things that can affect how successful this surgery is, such as:
- How healthy your child’s ears are. If your child’s cochlea doesn’t have very many nerve cells, the cochlear implant might not be as effective, because it can’t send as many sound signals to the brain.
- How old your child was when they went deaf. If your child goes deaf before they learn how to speak, cochlear implants might be less effective.
- How old your child was when they got the implant. Younger people have better results with cochlear implants.
- How long you have used the implant. When you get used to using the cochlear implant, it can work better than it did before.
If you and your doctor decide that your child should have cochlear implant surgery, your doctor will refer you to a clinic that specializes in installing these implants.
At the clinic, an audiologist [AW-dee-AH-low-jist] (a hearing specialist) and otolaryngologist [AH-tow-LAHR-in-JAW-low-jist] (a doctor who specializes in problems of the ear, nose, and throat) will do exams and tests to see if your child is a good candidate for cochlear implant surgery. Some of these tests include:
- Ear evaluation. The otolaryngologist will examine your child’s ear canal and middle ear to look for infections or other issues that could make surgery hard.
- Physical exam. The otolaryngologist will do a physical exam and ask questions to help find any complications or concerns for surgery.
- Hearing evaluation. The audiologist will do tests to see how much your child can hear with or without a hearing aid. These tests can see whether your child can hear sounds at different volumes and tones.
- Imaging tests. X-rays, CT scans, and MRIs can take pictures of your child’s inner ear to help their doctors prepare for surgery.
Cochlear implant surgery is an outpatient procedure, meaning that you come in to the clinic, have the surgery, and go home on the same day.
- Your child will be given a general anesthetic, a medicine that makes you sleep and stops you from feeling pain or remembering the surgery.
- To get to the cochlea, the surgeon might use what is called a mastoidectomy with facial recess approach, or MFRA. In this procedure, your surgeon makes a cut behind the ear to open the mastoid [MASS-toyd] bone, which covers the space in the middle ear.
- Next, the surgeon will open the cochlea, the part of your ear that contains the nerves that change sound into electric signals for the brain.
- The surgeon will install electrodes on the cochlea. These electrodes are connected to a receiver that is installed under the skin behind the ear.
- The surgeon will close the cuts they made to install the cochlear implant.
The surgeon will be able to tell you if the implant was installed successfully right after the surgery.Cochlear implants take time to get used to, and your child will need to adjust them and learn how to use them over time. It might take weeks or months before they know how well the cochlear implants are working.
In the weeks after the surgery, your child’s doctors will place the signal processor, microphone, and implant transmitter outside of your child’s ear. These are the parts of the cochlear implant that pick up sound and send it to the receiver and electrodes in the ear. During the follow-up, your child’s doctors will:
- Adjust these parts of the implant so that they sound better.
- Train your child to listen to sound with the cochlear implant.
- Talk to you and your child about how to take care of your implant.