KOCHI: Helen Keller — an American author, disability rights advocate and political activist — lost her sight and hearing while she was a toddler. She wrote in her memoirs, “If I were to be born again and had to choose between blindness and deafness, I would choose to be blind. Deafness is worse than blindness. It is the loneliness, the sense of isolation and the lack of understanding among hearing people that makes it so”.
In society, generally, people with blindness might receive sympathy but many times the deaf is looked down on with contempt and ridicule. Deafness is a very common ailment. It affects everyone in their old age and is usually mild. Most people might now be even aware of the problem.
Hearing loss in children
However, the most devastating is the hearing loss among children, mainly children born with it. The incidence of hearing loss in the newborn is about 1 per 1,000 live birth. Of all the five senses, hearing is the only one that can be restored. In newborns, it has to be addressed as early as possible because unless the baby hears the baby will not speak. We pick our language, dialect and accents from what we hear. So hearing is a prerequisite for speech.
Adults who have lost their hearing after they have acquired speech either due to infections or accidents also have to be helped to live a quality life.
A solution
Cochlear implants can help both children and adults with profound hearing losses where a hearing aid or medications will not be useful. In children, it has to be done as early as possible for clarity of speech. The time between six months to three years is ideal for cochlear implantation.
The ear is a very complex organ. It can pick up even minute sounds like the gentle rustling of the leaves and at the same time hear a roaring jet. It can localise where the sound is coming from with an accuracy of plus or minus 1 degree. The ear can also shut down unwanted sounds. A cochlear implant, especially if given in both ears in a child, can mimic most of the above capabilities of the ear. It will help the child to attend school and live a quality life.
How it works
The implant takes up the function of the cochlea (inner ear) and converts sound energy into electrical energy by directly stimulating the nerve endings. It has two parts. One is called a receiver-stimulator implanted into the cochlea through an operation. The other is a speech processor that is worn behind the ear like a hearing aid.
The speech processor has a microphone and it picks up sound and sends it to the processor. It splits the sound into frequency bands and converts it into electrical signals. This processed sound is sent to the receiver-stimulator in the cochlea and from there to the brain.
Who can use it
Patients suitable for cochlear implantation need to undergo a series of complex tests. They are otoacoustic emission test (OAE), brainstem evoked response audiometry (BERA) and Auditory steady-state response (ASSR).
Patients also need to do CT scans and MRIs. These are used to assess the suitability of the patient for the surgery and the condition of the nerves and inner ear.
The surgery lasts about two to three hours and the patient can be discharged the next day. After the surgery, one needs to undergo auditory rehabilitation.
Key to the success