While hearing aids work for most people with hearing loss, there are people with severe to profound hearing lossfor whom hearing aids are not advantageous. People with severe damage to the sensory cells in the inner ear need cochlear implants to hear better These tiny Cochlear implants are a class apart from hearing aids! Hearing aids enhance hearing of people with residual hearing ability by amplifying sounds. The Cochlear implants provide the sense of sound by stimulating the auditory nerve directly. Cochlear implants do not cure hearing loss or restore hearing, but they do provide an opportunity for the severely hard of hearing or deaf people to perceive the sensation of sound by bypassing the damaged inner ear.
How do cochlear implants work?
A cochlear implant has external and internal components. The external part hooks over the ear and there is also a surgically implanted internal part. The two components are coupled using a powerful magnet. The external component contains a microphone, a speech processor and a transmitter. The microphone and speech processor are housed in a small unit that looks like a behind-the-ear hearing aid. A small wire usually links them to the transmitter, which is positioned over the internal part of the device. The microphone picks up acoustic sounds and sends it to the speech processor. The processor analyzes and digitizes the signal before sending it to the transmitter. The transmitter, then codes the signals and sends them to the implanted receiver via the magnetic coupling.
The internal part of a cochlear implant includes a receiver, which is located under the skin on the temporal bone, and one or more electrode arrays. The receiver collects the signals from the transmitter and converts them to electrical pulses. It then dispatches the pulses to the electrodes that have been inserted deeply into the inner ear. These electrodes directly stimulate the auditory nerve throughout a portion of the cochlea and the brain then interprets these signals as sound.
Adults or kids - Who can opt for cochlear Implantation?
Depending on the extent of hearing loss, both children and adults can go in for cochlear implants. It is up to their doctor and decided after doing extensive diagnosis.
When it comes to kids, Cochlear implants can be done for children as young as 12 months old. Experts recommend implantation as early as possible to expose children to sounds during the critical period of language acquisition. After implantation, speech and language therapy is a must to achieve the best possible outcome from the device.
Children are considered viable candidates only if they:
Have profound hearing loss in both ears.
Get little or no benefit through the use of hearing aids.
Are healthy and fit for Implant surgery.
Can comprehend (when able), along with their parents, their role in the successful use of cochlear implants.
Have support from an educational program that will develop auditory skills.
As for adults, they may qualify for cochlear implantation regardless of whether they lost their hearing before or after learning language. Adults who had developed language before losing their hearing have greater success with cochlear implants than those who had not developed language before losing their hearing. Adult candidates qualify for an implant if they:
Have severe or profound hearing loss in both ears.
Get little or no benefit from hearing aids.
Are healthy & have no medical problems that could put them at risk during surgery.
Strongly desire to be part of the hearing world and communicate through listening, speaking and speech reading.
Cochlear Implant – How to go about it?
You need to pass a medical evaluation and several counseling sessions before you venture for Cochlear Implantation. An ENT physician or an audiologist can give you a referral to a cochlear implant center. Here extensive audiologic and psychological testing, a medical exam and imaging studies are done to determine if they will benefit from a cochlear implant. Then there will also be counseling for the candidate, to make sure he or she - or parents, for a child - understand the large follow-up commitment required after the implant surgery, as well as what to expect regarding device performance and limitations.
Now coming to the actual facts on the Cochlear Implantation Surgery! The surgery, which typically takes between two and four hours is done under general anaesthesia. Most people spend one night in the hospital afterwards. But the patient will not be able to hear yet even though the internal components have been placed, the surgical site must heal before the external device is placed.
The beginning of a new hearing journey…
Four to six weeks after the surgery, the patient will be fitted with the external device & the audiologist will activate the cochlear implant device. He will begin the process of mapping the processor for the individual's specific needs.
It is a great experience to hear sounds for the first time when the cochlear implant is "turned on". Whether it is the first hearing of own voice or a loved one’s voice, it's quite an emotional and memorable milestone for the patient or parent.
Things to do after cochlear implants?
The first appointment will be followed by others for fine-tuning and adjustments to the cochlear implant map. Many follow-up visits are required over several months to adjust the mapping of signal to the electrodes, as well as to help the person become accustomed to his or her device. Especially for those who've never heard sound before, an auditory training program is necessary to help the brain learn how to process the new auditory stimulation. Much like hearing aids, individuals will want to schedule regular visits with their audiologist for occasional adjustments and hearing tests.
Things to look out for after Cochlear Implantation
Treat ear infections at the earliest
Avoid using treatments involving electric current or strong magnetic fields to the head or neck.
Avoid MRI scans unless recommended by an ENT doctor.
Take pneumococcal immunization in patients with cochlear implants in addition to their childhood immunization.
Avoid using induction cookers and security scanners.
The patient should not move unnecessarily or scratch the area above the implant area and should avoid mechanical pressure over the area.
The chances of head injury are high in sport events. Use helmet and take precautions while motorcycling and boxing.
Consult an ENT doctor before snorkeling or scuba diving.
Do not use dangerous machines or high voltage equipment to avoid damage to their Implant devices.
Some audio processors may interfere with reception when using certain TV sets. Avoid such cases.
Mobile phones and communication devices may interfere with the parts of the cochlear implant system if they are used within a distance less than 9.84 feet.
The audio processor should not be connected directly to any equipment connected to an electrical outlet.
Guide lines for children with cochlear implants
Children with cochlear implantation done have to be extra careful while participating in contact sports like Martial Arts, Kick Boxing, Rugby, Lacrosse, Football, Basketball etc. Chance of injury is on the higher side for kids with cochlear implants and hence helmets should be used to protect the head. A blow to the head may damage internal devices of the cochlear implantation and surgery will have to be done again in some cases.
Put safety locks to prevent kids from disassembling the audio processor as there is a danger of swallowing implant components.
The Ascent ENT Hospital, Malappuram is one of the state of the art ENT Hospitals in Kerala with the best ENT Doctors in India to conduct Cochlear Implantation surgeries. Our ENT specialists provide all guidelines and thorough regular check-ups to patients with hearing loss and ear problems. The Ascent ENT team is well versed in dealing with modern equipment and devices of implantation and has conducted many cochlear implantations successfully.