Cochlear implants have revolutionized the lives of individuals with severe hearing loss, offering the possibility of restored functionality and improved perception of sound. However, it’s important to understand cochlear implants pros and cons before making a decision. On one hand, cochlear implants can significantly enhance hearing and speech perception, benefiting both adults and children. On the other hand, there are potential risks, such as the loss of residual hearing and the need for surgical intervention.
In this blog post, we will delve into the advantages and drawbacks of cochlear implants, providing you with a well-rounded understanding of this transformative technology.
What Is A Cochlear Implant?
A cochlear implant is a medical device designed for people who have too much hearing loss to receive adequate benefits from traditional hearing aids. Cochlear implants are a treatment option for patients of all ages, from babies who receive a diagnosis of hearing loss at birth all the way up to elderly adults who are healthy enough for surgery. A cochlear implant is considered a Class III medical device in the United States, which means they are highly regulated by the Food and Drug Administration (FDA). There are currently three FDA-approved manufacturers of cochlear implants in the US.
What Is The Difference Between Hearing Aids And Cochlear Implants?
Hearing aids use the traditional sound pathway to acoustically amplify sound in the areas where hearing loss is present. With normal hearing, sound travels into the ear canal, through the middle ear space via the ossicles, and into the inner ear, where tiny hair cells move in the fluid-filled cochlea to send a signal to the auditory nerve and to the brain.
A hearing aid uses this same pathway but simply captures the sound at the level of the ear and makes it louder as it travels down the ear canal. (Note that hearing aids are much more sophisticated than just making the sound louder, but we want to focus on the pathway being used!)
Cochlear implants, on the other hand, are creating a new pathway for hearing. An electrode array is inserted directly into the cochlea to essentially take the place of those tiny hair cells, which are damaged or dysfunctional in a person with considerable hearing loss. The external portion of the cochlear implant, known as the sound processor or speech processor, picks up sound and transmits it to the electrode array, which stimulates the auditory nerve and the brain.
How Does A Cochlear Implant Work?
The internal device is made up of two parts: the electrode array inserted into the cochlea and the “internal cochlear stimulator,” which houses the electronics and sits under the skin on the temporal bone of the skull.
This piece has a magnet inside, as does the external sound processor. The two magnets allow antennae to align and communicate with each other; this communication involves converting acoustic information picked up by the microphones on the sound processor to electrical impulses sent via the electrode array. The sound processor is often worn on the ear with a cable that attaches to the magnetic headpiece. Some manufacturers offer single-unit processors encompassing the electronics and the magnet, and all offer different wearing options to have the processor worn off the ear with a longer cable to attach to the magnetic headpiece.
The Cochlear implant surgery is performed by a physician specializing in ears, known as an otologist, otolaryngologist, or neuro-otologist. Patients undergo general anesthesia for the procedure. An incision is made behind the ear being implanted, and the surgeon drills into the temporal bone to create a pathway to insert the electrode array. The remainder of the internal device is placed upon the skull, occasionally with a shallow well drilled into the skull so that it is seated tightly. Usually there is some intra-operative testing performed on the device at the very end of the procedure to confirm that the auditory nerve is responding to the stimulation.
While the surgery for a cochlear implant might sound intimidating, it is usually an outpatient procedure that takes about 90 minutes. Most patients go home the same day and are treated with mild painkillers such as Tylenol or Advil. When the incision has healed a couple of weeks after surgery, the patient returns to have the implant “activated,” meaning the sound processor is turned on and programmed, and the patient will begin hearing the sound.
It often takes several visits to the audiologist early on to program the implant to receive adequate access to sound. Many audiologists will use something called “progressive programs” to allow the patient to add a bit more stimulation each day as their brain adjusts to the new sound quality. The audiologist will perform testing to determine how much sound the patient is receiving from their implant, and after a few weeks may perform some tests of discrimination ability to see how well the patient is understanding speech with their implant.
There is a lot of variability in how long it takes for patients to get used to the sound of a cochlear implant, but wearing it during all waking hours is the best way to start. The audiologist has flexibility in the programming software to make adjustments but will heavily rely on your reports of loudness and comfort of what you are hearing. An audiologist can listen to a hearing aid and have a general sense of how it is working, but only the patient knows what their own cochlear implant sounds like. The relationship between the patient and the audiologist and their communication is critical.
Who Should Use A Cochlear Implant? Am I A Candidate?
Cochlear implants are designed for people who cannot receive adequate benefits from hearing aids. The evaluation has two main parts to determine candidacy for a cochlear implant. The first is the diagnostic hearing test, which measures the softest possible levels a patient can hear at various frequencies (pitches) in each ear.
This test is performed under headphones in a soundproofed booth. Candidates for cochlear implants typically present with severe to profound hearing loss in children and moderately severe to profound hearing loss in adults. The second part of the evaluation is discrimination ability with appropriately fit hearing aids. The audiologist needs to be able to show that, even with hearing aids, the patient is missing a large percentage of meaningful speech. There are a couple of different tests, some of which use single monosyllabic words and others which use sentences, which are presented to the patient in the soundproofed booth with their hearing aids on. The performance on these tests needs to be below a certain percentage in addition to the results on the audiogram in order to be considered a candidate for a cochlear implant.
If a patient is deemed an audiological candidate, they would also need to be seen by a surgeon to determine medical suitability for surgery. As mentioned, the procedure takes place under general anesthesia. The surgeon will also make a referral for a CT scan in order to examine the anatomy of the inner ear within the temporal bone. Sometimes the etiology of the hearing loss is unknown, and the CT scan will give the surgeon an idea of where the cochlea is positioned and confirm that the insertion of the electrode array will go as expected. For some patients, and especially for children, the surgeon may also recommend an MRI. A CT scan shows bone, while an MRI shows soft tissue. The MRI will help the surgeon to determine the presence or absence of an auditory nerve if that is a concern. There are some rarer etiologies of hearing loss for which a cochlear implant would be contraindicated, such as the absence or severe malformation of a cochlea or the absence of an auditory nerve. If you are an adult who has experienced hearing loss over time and has successfully used hearing aids, this is not a concern.
If you have noticed that you are having increasing difficulty hearing with your hearing aids, it is a good idea to discuss cochlear implants with your provider. They can recommend a cochlear implant center in your area (if you are not already being seen at a larger hospital/university setting that offers cochlear implants) where you can schedule a candidacy evaluation. There are a lot of fantastic resources out there from the centers and from the manufacturers to learn more about cochlear implants and to connect with other individuals who have gone through the process. Even if you have an evaluation and the audiologist determines that you are not a candidate, you have established a relationship with a center and a baseline evaluation.
If the cochlear implant team determines that you are a candidate, they will likely ask you to research the three manufacturers: Advanced Bionics, Cochlear Americas, and Med-El. It is common at many centers to offer all three devices but leave the decision up to the patient or parents. This can be quite daunting, but each of the companies has unique selling points and reasons why a patient might choose to go with that device.
There are brochures and websites, and each of the manufacturers also has a local team of professionals who can set up a time to meet with you virtually or in person to learn a bit more about your story and talk about their device. These local representatives are also available to continue to support you on your journey after you have received your implant, and many cities have very active support groups which host social gatherings and educational events to meet other people with cochlear implants and their families.
What Are The Pros Of Cochlear Implants?
For people who are candidates for a cochlear implant, it restores access to sound that they could not otherwise hear with hearing aids. Children who are implanted early, wear their device consistently, and receive adequate therapy are generally tracked into mainstream schools and develop completely normal speech and language. You often cannot even tell they are using a cochlear implant (or two cochlear implants, as is common with children) unless you can see the processors. Adults who are implanted post-lingually, meaning after they have developed speech and language, also tend to have quite positive outcomes. In particular, adults who have had a shorter duration of hearing loss and/or have been consistent hearing aid users since their hearing loss was detected tend to be great performers with a cochlear implant.
Introducing (or re-introducing) adequate access to sound can have huge benefits, including increased opportunities for social interaction, greater comfort and confidence in communication at school or work, and the ability to participate in activities in more challenging listening environments. There is substantial evidence to support intervention for hearing loss as a way to mitigate the risk of dementia and general cognitive decline. Family members and friends of cochlear implant users often report greater ease and reduced stress in communication with their loved one with hearing loss, and it is very common for cochlear implant recipients to say they wish they had been implanted sooner.
Another benefit of cochlear implantation is that if you are deemed an audiological and medical candidate by your audiologist and surgeon, your insurance company will likely pay for the cost of the surgery and associated devices. The same cannot be said for insurance coverage for hearing aids by most insurers.
Your provider will most likely need to write a letter of medical necessity to your insurance company which describes the nature of your hearing loss, your limited benefit from hearing aids, and the potential for improved performance with a cochlear implant. This is something that providers are accustomed to writing, and each of the manufacturers of cochlear implants also offer assistance with insurance coverage.
What Are The Cons Of Cochlear Implants?
The biggest obstacle for most patients to move forward with a cochlear implant is fear of the unknown. There is no surefire way to predict performance with a cochlear implant, though the vast majority of patients perform better with their implant than they did with hearing aids. There are many factors that can influence outcomes with a cochlear implant:
- Age at onset of deafness
- Duration of hearing loss
- Age at the time of implantation
- Residual hearing
- Etiology of hearing loss
- Multiple handicapping conditions
Based on these factors, providers can often try to set realistic expectations for patients about the type of performance they can expect from a cochlear implant, though there is never a guarantee. For this reason, many adult patients choose to have their poorer ear implanted with the hope that they can continue to rely on the hearing aid in their “better” ear. There are mixed opinions on this tactic. Evidence shows better outcomes with a cochlear implant when there is more residual hearing in the implanted ear, and many providers strongly encourage patients to spend some period of time with their cochlear implant only to force their brain to adjust to the new sound quality rather than using the hearing aid as a sort of crutch.
Once the cochlear implant has stabilized a bit, most providers recommend “bimodal” use, which means a cochlear implant on one ear and a hearing aid on the other ear. Two ears are better than one, and many patients find a good balance between their two devices. Other patients may choose to have their other ear implanted at a later date, though this is historically more difficult to get insurance to cover than the initial surgery. It is much more common for children to have bilateral cochlear implants, either implanted simultaneously or sequentially based upon the preferences of the parents and providers, the etiology of hearing loss, and the health of the child.
This adjustment period can sound like a “con” for some patients, but the brain is extremely plastic and adaptable. The more a patient uses their device, and in a variety of different listening situations, the more quickly the patient will adjust to the new sound quality. This anecdote from a former patient describes the process well. He underwent cochlear implant surgery and had his sound processor activated about three weeks later. Within the first week, he was at home and heard a “weird” sound. He began walking around his house, trying to determine what the sound had been, and realized it was the doorbell. The next day, the doorbell rang again. This time, he wasn’t thinking that it sounded weird, he had an instant connection between that sound and the doorbell. The brain has to make thousands of these connections over and over again with the assistance of auditory memory, but over time the cochlear implant begins to sound “normal.”
One potential obstacle to cochlear implantation is access to a center. Some areas of the country have many hospitals and clinics that offer cochlear implants within a small radius, while others do not. In the beginning, there are many appointments to make adjustments to the cochlear implant as the brain adapts to the new sound quality. For patients who live a few hours from their center, access to care can be quite difficult.
Additionally, many providers will make a recommendation for aural rehabilitation (particularly for children, but also for adults) to really focus on listening practice and tools to improve hearing performance. These would be additional trips to a provider who may live quite far away. All of the manufacturers, and all of healthcare in general, is increasingly working to improve telehealth availability across a range of services. There are some fantastic aural rehabilitation resources that can be accessed from a distance, but remote programming of the device itself is not quite there yet.
Cochlear Implants Pros And Cons Conclusion
In general, the pros of cochlear implantation far outweigh the cons, particularly because many of the potential negative points (fear of surgery, adjustment to sound quality, period of time without hearing aid on the opposite ear) are typically conquered very early on in the process. Patients consistently report they wish they had moved forward with an implant sooner.
If you think you might be a candidate for a cochlear implant, you can reach out to your hearing aid audiologist and/or do some research on cochlear implant centers in your area to schedule a candidacy evaluation.
Erin Edwards received her Doctor of Audiology degree from Towson University in 2015 and her Ph.D. in Education and Leadership from Pacific University in 2022. She has worked with patients of all ages in a variety of settings and has a specific interest in cochlear implants, the relationship of hearing loss and dementia, and interdisciplinary healthcare.