The ideal choice of a hearing device is based on the medical and audiological response of the patient. Type and degree of hearing are major factors to decide the candidacy for a hearing aid or cochlear implant for the patient. This is decided by the ENT specialist and audiologist.
Both hearing aids and cochlear implants help the individual hear well. But it is important to identify the basic differences between the two.
How Does a Hearing aid and a Cochlear implant work?
The Hearing Aid is an electronic device which has an external microphone which picks up the sound and passes it on to the digital signal processor and amplifier. This amplified sound reaches the outer ear. The programming ensures that the amplification suits the user’s hearing loss.
A Cochlear Implant on the other hand, picks up the sound through an external microphone and passes it on to the Sound Processor which converts these sound waves into electrical pulses or signals. These signals, through a set of surgically implanted electrodes, reach the Inner Ear directly, bypassing the outer and the middle ear. If there is an abnormality with the outer, middle ear, a cochlear implant bypasses these and directly stimulates the Inner Ear (Cochlea).
It is clear from the above that we cannot replace one device with the other. Each Hearing Device has its distinct use and purpose.
To summarise the above. A Cochlear Implant suits the user if there is a damage or abnormality in the Outer Ear or the Middle Ear. The abnormality does not allow the sound to reach the Inner Ear. Hence the need for the sound signal to directly reach the Inner Ear.
Candidacy for Cochlear Implant
The following are the criteria for getting a Cochlear Implant.
- No benefit with hearing aid – Poor or no change in speech scores after 3 months of hearing aid usage.
Type of Hearing Loss – Hearing loss which is not reversible with no residual hearing (no benefit with hearing aid) can consider cochlear implantation.
Poor quality of speech with hearing aid – Even after prolonged use of hearing aid, a person is not able to appreciate speech even in a quiet situation.
Age when hearing loss was identified– Children who have congenital hearing loss will best benefit from cochlear implantation. Furthermore, adults who with no residual hearing will benefit better than older adults.
Patient support system – Family and caregiver support is crucial during and after the implantation to adjust to the new way of hearing.
Post-Operative Expenses – Having the surgery doesn’t mean there are no further costs involved. The person should be able to afford the regular maintenance, auditory training and upgrades involved.
Who should use a Hearing aid?
- When an individual is diagnosed with a hearing loss in one ear or both ears, the first choice should be a hearing aid.
- If a person has some residual hearing and can understand speech.
- Hearing aids can be easily handled and are well accepted among individuals of all ages.
- Elderly patients who cannot undergo a surgery should opt for hearing aids.
It is important to remember that with either of the devices, hearing loss cannot be reversed. But one can obtain optimum benefits with training and regular use.