A cochlear implant is a device that can improve hearing in patients who are not getting adequate help from hearing aids. The device consists of an internal implant and an external piece that sits on the outside of the ear. The implant is placed under the skin near the back of the ear. It includes a wire and some electrodes that travel to the cochlea – a part of your inner ear. The external piece includes a speech processor and a microphone.
Cochlear implants take time to learn how to use, but they can significantly improve the quality of life for those that use them.
How does a cochlear implant work?
Cochlear implants work by converting sounds into electrical signals, which are then sent to the cochlear nerve through an electrode and then interpreted by the brain as sound.
A cochlear implant does not amplify sounds like a hearing aid. Instead, it processes sounds and sends useful signals to the inner ear – skipping the parts of the ear that do not function properly and going straight to the auditory nerve. When the inner ear receives the signals, it perceives them in a similar way to the way it perceives sounds.
What are the benefits of a cochlear implant?
Using a cochlear implant does not cause the ear to hear in the same way a normal hearing ear does. Still, it does offer benefits, however, particularly for those that miss spoken words regularly and rely on lip reading. Although it takes time to learn how to use it, a cochlear implant can often improve the ability to understand speech and their ability to detect warning sounds.
A cochlear implant gives the user feedback on the sounds that are occurring around them. Even if it is not the same as regular hearing, it is still a valuable tool that patients can use to perceive sound and act on what they are hearing. It can help improve speech recognition in background noise, with and without lip reading. It can also make it easier to enjoy things like watching television, listening to music and talking on the phone.
Other benefits of getting a cochlear implant include the ability to differentiate between sound levels and improve sound localization. Many users also experience an improved ability to identify sounds that are soft, medium and loud.
Not being able to hear adequately can affect us in many ways, potentially reducing work productivity, limiting social interaction and impairing quality of life. There is also emerging evidence loss of hearing may accelerate loss of cognitive function in elderly patients and be a risk factor for dementia.
Cochlear implant vs hearing aid
Cochlear implants and hearing aids are both designed to help users improve their hearing, but they work quite differently. While hearing aids can be taken in and out at will, cochlear implants are implanted into the body by a surgeon. Hearing aids are most often used by patients who still have some residual hearing. In contrast, cochlear implants are used by patients who are deaf or nearly so.
If a patient still has some ability to hear, a hearing aid is the first choice because it is the easiest to use and the least invasive. A hearing aid will amplify sounds so the patient’s residual hearing can more readily pick them up and process them. But if the patient has little or no ability to hear sounds, it doesn’t matter how much you amplify the sound. A cochlear implant bypasses the damaged hearing and goes directly to the auditory nerve to provide a sense of sound that the patient can learn to use over time.
Cochlear implant surgery is an inpatient procedure that can be completed in two to four hours.
Before surgery, you will be given general anesthesia. The surgeon makes an incision in the skin behind the ear and then makes openings to reach the cochlea – through the mastoid bone, the facial recess and the cochlea. Once they access the inside of the cochlea, the surgeon places the electrodes and the receiver under the skin in the area behind the ear.
Once everything is in place, the surgeon closes up all the incisions and you are placed in the recovery area and observed overnight in the hospital.
It takes some time to recover from the implantation of the cochlear implant, recovery that must be completed before the surgeon can activate your implant. The surgeon will give you instructions on how to care for your incisions, such as how to change your dressings and how to take care of your stitches. After a few days, you can wash your ear as you normally would.
If you experience fever, significant pain or drainage, you should contact your surgeon’s office and notify them.
Your surgeon will most likely want to see you about a week after the surgery to check up on your condition and may remove stitches. It will take two to four weeks for the external pieces of the implant to be attached and placed on the outside of your ear, including the microphone and the speech processor.
When the external parts are added the speech processor will be initially tuned and you will be taught how to use the implant. Keep in mind that it usually takes some time and adjustments to make the implant work as well as possible for you specifically. That means you will need to go in and get the device tuned several more times over the following months. You will also need to work with audiologists and speech-language pathologists to gain full proficiency with your implant.
Learning to make the most of your implant will take time – more time than the surgery and recovery took. But the hard work will pay off by improving the quality of your life and your perception of the world around you.
What are the risks of surgery?
Cochlear implant surgery is a common surgery and is considered safe. Still, it also carries risks of complications just like any other surgery. These include:
- Wound complications: swelling, bleeding and infection
- Loss of residual hearing or poor hearing benefit. New or worsening tinnitus
- Dizziness and vertigo.
- Facial paralysis and electric stimulation caused by the electrode activity. Altered taste.
- Leakage of spinal fluid and intracranial infection
- Infection or malfunction of the cochlear implant device that may require its surgical replacement.
What other tests will I need before Cochlear Implant surgery?
Cochlear Implant candidacy assessment will require further investigations; including Audiological testing, Imaging (MRI and/or CT scans) and Balance tests, among other investigations.
Am I a candidate for Cochlear Implant?
Our Ear, Nose and Throat specialist will gladly discuss in further detail if you, or any person you know, could benefit from a Cochlear Implant.