Hearing loss is something experienced by more than 48 million Americas, and while there is no known cure, there are treatment options available for the majority of cases. Hearing aids are often a great solution for those with hearing loss ranging from mild to severe. However, hearing aids cannot treat every hearing loss, and some people may need to seek other options. For many, the solution is cochlear implants.
In 2012, there were a reported 324,200 cochlear implants used worldwide. Today, that number is steadily increasing as cochlear implant technology becomes more advanced. With so many people taking advantage of this technology, it's important to be aware of how cochlear implants work and why someone would receive an implant instead of a hearing aid.
Why Choose a Cochlear Implant?
The most common type of hearing loss is sensorineural hearing loss. Sensorineural hearing loss means that there is damage to the little hairs in the cochlea. With injured hairs, sound cannot travel to the auditory nerve. Both hearing aids and cochlear implants are used to help people with sensorineural hearing loss hear better; however, there are big differences in how they work.
Today's hearing aids do many things—like automatically adapting to noisy environments, reducing wind noise, etc.,—but one important thing they do is to amplify sound. This is extremely helpful for people who have enough hearing to work with; however, some people don't have enough hearing left, therefore don't fully benefit from a hearing aid.
For those with sensorineural hearing loss who do not benefit from hearing aids, cochlear implants may be the best option. A cochlear implant is a surgical procedure. While hearing aids work with your existing hearing and adjust accordingly, a cochlear implant replaces the function of your inner ear and hearing.
The Components of a Cochlear Implant
There are two parts to the cochlear implant: an external processor, and the internal implant. Doctors place the magnetic implant in the recipients' head with a cochlea to bypass the damaged hair cells. An external processor is removable and attaches to the internal implant via the magnet, which, when connected, has microphones that take in sound.
The external processor has multiple parts to it. The overall shape is very similar to a hearing aid, and it has microphones that receive sound. Some people opt to have an ear mold for extra security so the implant doesn't fall off, but that is simply an accessory. Ear molds are not needed for the cochlear implant to work. The main difference between the physical components of hearing aid and a cochlear implant processor is that there is a magnet attached to the implant.
Taking the external processor on and off does not hurt. In fact, cochlear implant users forget that it's even on their head! Think of it like wearing a pair of glasses or sunglasses. It's a bit unusual at first, but after getting accustomed to it, you forget you're wearing them.
The internal implant is not visible to anyone, since it is surgically placed under the skin. It has a circular magnet similar to the external processor, an antenna wrapped around the magnet with the receiver and simulator, and two "strings."
The two "strings" are actually electrode wires. The electrode array is in the same shape as the cochlea and is placed there to replace it. They also stimulate the auditory nerves, so that's how the sound is then received by the brain.
Now you know what the components of a cochlear implant are, here's how the process in which sound is heard!
How It Works
When a cochlear implant user turns the processor on, places it behind the ear, and attaches the external magnet to the internal magnet, the following happens in seconds:
First, sound is received using the external processors microphones that are on the top of the body. That sound gets sent to the processor part on the implant. In the diagram, the processor is the base of the body of the implant.
The sounds received are then converted to coded signals in the processor. These signals are transmitted to the internal implant, which is under the skin. Remember: this exchange only happens when the two magnets are attached.
The internal implant has the receiver and electrode stimulator parts. The coded signals from the processor are received and then translated to the electrode simulators.
Then the electrode simulators send a tiny electrical charge to the fibers of the auditory nerve to give sound sensations. Those sound sensations are immediately given to the brain to recognize.
All of these parts are shown in the diagram below.
Image Credit: New York Eye and Ear Infirmary of Mount Sinai
Benefits & Risks of Cochlear Implants
Making the decision to receive a cochlear implant is a big one! There are both benefits and risks to consider.
Some risks include:
Know that receiving a cochlear implant is a surgical procedure, which always has risks associated with it. Anesthesia is used; however, cochlear implant surgery is an outpatient surgery that requires a small incision behind the ear. It is noted as a low-risk procedure.
After the procedure, the implanted person will not be allowed to have MRI's. MRI's use magnets, so alternate forms of medical imaging will have to be used, such as ultrasounds or CAT scans.
It is a lifetime change. The surgery removes all preexisting hearing from the ear in order to replace it. After being implanted, the user cannot use hearing aids again. However, the high success rates with cochlear implants make the change worth it for users.
Success is dependent on the user. A big qualification is whether or not the implanted person is willing to put in the work to optimize the cochlear implant's technology. Everyone's experience is different.
The benefits include:
For many, there is a higher chance to hear better than with a hearing aid. This is a big factor that leads people to receive a cochlear implant.
Since hearing is completely replaced, the cochlear implant recipient has the opportunity to adjust all of the levels via their hearing health care provider's software technology.
The implant microphones can focus where sound is received and adjust to noisy situations. Regular programming checkups allow for adjusting the settings and using various tools in order to best utilize the microphone's capabilities.
For those who lost their hearing later in life, they can reconnect to lost sounds or hear new sounds. This is an experience that is truly one of a kind.
Several studies show that sentence understanding is higher with cochlear implants versus hearing aids. In fact, studies show that there is an 80% sentence understanding after six months of implantation. This proves that, for those who have had limited success with hearing aids, cochlear implants will greatly improve their hearing experience.
Are Cochlear Implants Right for You?
Not everyone is eligible to have cochlear implant surgery. There are certain qualifications to be met.
Here are some general qualifications you need to have:
- Children 12-24 months old need to have profound sensorineural hearing loss
- Children 2-17 years old need to have severe to profound sensorineural hearing loss
- Individuals 18+ should have moderate to profound sensorineural hearing loss
- If hearing aids do not provide any assistance, this increases your chances of qualifying
- Ideal candidates are motivated to work hard in rehabilitation
- Candidates must score 65% or less on sentence recognition tests done by hearing professionals
Cochlear implants require someone who is willing to put in the work. Turning a cochlear implant on for the first time isn't the end all, be all. It takes time to train your brain to get accustomed to the technology. You are replacing your hearing with machinery!
Speech therapy and multiple hearing healthcare provider visits in the post-surgical phases of receiving the cochlear implant surgery is what will set the implanted person up for success. Having a strong support system, such as family, friends, and coworkers will help the user stay motivated and on the right track. Patience is important all around.
Of course, speaking to your hearing healthcare provider is the best way to find out if you qualify!
So, What Do I Do Next?
Now that you know more about cochlear implants and how they work, share this article with your family and friends to educate them! Most people do not know how cochlear implants work, and it's very important to educate others about this technology.
If you think you or a family member could benefit from a cochlear implant, speak to your local hearing healthcare provider today. If you find out that you do not qualify, you may benefit from a hearing aid.