“SOPHISTICATED HEARING AIDS SOUNDING THE DEATH-KNELL FOR SCHOOLS FOR THE DEAF”
Dr Shaila Vora
Gone are the days when children born with hearing problems had to go to schools for the deaf and dumb .
Most of those schools are closing down because the new generation hearing aids are so good and the technology so sophisticated that the children pick up sounds like normal children.
If they are fitted with these instruments within the first one to two years of life, they pick up hearing quickly and are able to go to regular schools and to speak normally.
Of the five senses, four become dormant at night but hearing does not;the sense of hearing keeps one alert round the clock. But when hearing loss sets in, those affected become selective hearers; once they start wearing aids, they have to learn to adapt to it.This takes time, unless the wearer and his/her family members are motivated.
These are some of the bits of crucial information that emerged from a presentation made at the last meeting by Dr. Shaila Vora, a practising audiologist and speech and language therapist.
She made another two key observations in response to questions at the end of her talk.
First, when asked whether more numbers of younger people were turning deaf because of the music blasting through their headphones, she said this was true. Earlier, she rarely saw people aged between 30 and 40 turning deaf. But now there were at least two to three such cases every year, most of them with exposure to loud sounds.
Secondly, it was not possible to say with any conviction that the use of mobile phones was affecting people’s hearing. “We have to wait for a long time and for scientific studies to know for sure,” she added.
Dr. Vora was introduced by Jagdish Malkani who said that she had been an audiologist for 35 years and also practised yoga, performed classical Indian dance and was known for rendering traditional thumris with flair. A Rotarian, she was an active Rotaractor as a collegian.
The guest speaker started her presentation, which was peppered with a few audio and video clips, by explaining how sound was produced and how it was heard by human beings.
“When a stone is dropped in water, we see the ripples it creates. In the same way, pressure ripples are created in the air when sound waves are produced.”
The human ear had three main parts. The outer ear, or the pinna, which received sounds. The pinna led to the ear canal where wax was formed (wax formation was a natural way of keeping the ear moist and protecting it from infections).
Next came the ear drum. When sound waves fell on it, the ear drum moved and the sound was passed on to the middle ear. There were three small bones in the middle ear (these were the smallest bones in the body) which took the vibrations and passed these on to the inner ear.
The inner ear had a thin membrane called the organ of Corti. When the three small bones in the middle ear vibrated, the vibration went to the Oval window which was the second curtain of the ear, between the inner and the middle ear.
Inside the Oval window was the cochlea which had a thin membrane with several hair-like cells. When sound waves were received by it, the membrane also moved like the ripples (seen in a pond when a stone was thrown).
“When the membrane moves, the hair cells on the membrane move, and when the hair cells move, that is the God-given amplifier. If I am talking to you at a 40-decibel level, the cochlea will amplify it and make it 140 decibels and only then is the message sent to the brain.”
As the hair cells moved, they created electro-magnetic impulses which were sent towards the brain. It was the nerves that then took the message to the brain. Thus, the hair cells moved up and down and the electro-magnetic impulses they created were sent to the brain.
What this meant was that one did not hear through the ears, but at the brain level.
Turning to hearing losses, Dr. Vora said these were of two kinds, at the conductive level and at the sensory level. Conductive hearing loss was caused because of outer ear and middle ear problems.
Sensory hearing loss, on the other hand, was due to inner ear problems. Moreover, sensory hearing loss was irreversible and was caused by the ageing. Every person was going to suffer hearing loss.
What did ageing do to the hair cells? The hair cells on the membrane in the cochlea turned bald as a person aged. The process of turning bald was similar to men becoming bald and losing the hair on their heads. This balding of the hair cells in the cochlea caused irreversible hearing loss.
The work of the cochlea, which was a God-given amplifier, could be taken over by a hearing aid which amplified sound from the exterior canal itself and sent the message to the brain.
Dr. Vora then presented a few audio and video clips to explain how different sounds, such as the chirping of birds, sounded to normal people and to those with hearing loss.
Dr. Shaila Vora lists the steps to follow in the selection of a hearing aid
As and when such symptoms occurred, it was best to go to an audiologist who was a super- specialised professional in the field of hearing. Just as here were cardio-surgeons and cardiophysicians, in the field of ENT there were only surgeons. The physical side was looked after by audiologists or language therapists.
They were certified by the Rehabilitation Council of India to practice in the area of hearing aids and for any hearing problems where surgery was not involved. Just as heart specialists had cardiograms, audiologists worked on audiograms. When an audiogram showed that a person?s hearing was within 20 decibels, it was considered normal.
There were several degrees of hearing loss. If the audiogram showed a result between minus 10db and 20 db, it was normal hearing. Between 25 and 40, it was mild loss; from 40 to 55 was moderate loss; between 55 and 70 moderately severe; and between 70 and 90 it was dubbed severe loss. If the reading was 90 or above, it was called profound loss.
Dr. Vora said that patients in Bombay usually visited an expert when the hearing loss was moderately severe to severe. Many people talked about 50% or 70% hearing loss, but some of them even had minus hearing.
What were the steps to follow in the selection of a hearing aid? There were three classifications:
(1) Cosmetic, which depended on looks or appearances. The instrument one chose did not matter because they all worked the same way; it was just a case of choosing a model that looked different.
(2) Technical. There were analogue and digital instruments and something in between called analogue-programmable instruments. But now digital aids were increasingly becoming dominant. The latest technologies were involved and one’s choice would have to depend on where one was going to use them. It was necessary to discuss one’?s daily routine with the audiologist before selecting an instrument.
(3) Economic. There were entry-level, basic level and advanced level instruments. One had to consider the ambient noise of one’s surroundings. For example, there was huge ambient noise in Bombay on account of which entry-level and basic level instruments would not do. One would have to go for advanced level aids. A simple entry- level instrument would work very well in the interiors where it was quieter and there was no ambient noise
Next, Dr. Vora touched on different types of cosmetic or fashionable instruments. These were mainly of three kinds, (a) BTE or behind the ear, (b) ITC or in the canal and which went right inside the canal, and (c) CIC or completely inside the canal; these were invisible, went right inside the ear and even the person one was speaking to could not see them.
The advent of the latest digital technology had brought in many different kinds of hearing aids; while some of these were for people with normal hearing and for the low frequencies, there were others for higher frequencies.
A few instruments were smaller than CICs, but others could be worn permanently till the battery lasted, perhaps for three months, and some could be removed.
Dr. Vora said that re-learning the process of listening was very important. If, after the advent of hearing loss, one took a long time to start wearing a hearing aid, then the re-learning process was crucial, otherwise one could become a selective hearer.
Normally, if one could not hear a few sounds, one felt better in the noisy environment of Bombay; one would then selectively hear only those voices that held some meaning, such as speech sounds. But that happened very rarely because a normal person would be better off if he heard everything around.
Hearing was a sense that remained alert all 24 hours. The other four senses remained dormant at night. (Atthis stage, Dr. Vora also stated that new technologies were sounding the death knell for schools for the deaf, as stated at the beginning of this report.)
The Rehabilitation Council of India, which was a statutory body of the Central government, pointed out that the Act of 1972 required audiologists to dispense hearing aids. Sadly, most people who required them did not know where to go or whom to contact. Audiologists also had to study for four and a half years after Std. XII (as for an MBBS degree).
But of late several MNCs had come into India and, over the last two or three years, appointed 2,000 to 3,000 non-audiologists. These people visited homes and helped with the fitting of the aids even though they were neither audiologists nor medically-trained professionals.
They were engaged in illegal practice and it was incumbent on patients to go to a qualified audiologist.
Other fraudulent practices could be seen at railway stations, in pharmaceutical shops and elsewhere where they offered hearing aids to everyone.This was an impossible proposition. Digital hearing aids required the patient to sit in front of an audiologist who did the fine-tuning. besides, fine tuning was required three to four times in the first one or two months before an affected person could benefit fully from it.
A digital instrument could be programmed ‘n’ number of times, even 100 times. If the user had any problems, such as irritability because of certain noises, dislike for some sounds and so on, these could be easily fine-tuned if one went back to the audiologist.
What were the myths surrounding hearing aids?
Dr. Vora said some people felt in the initial stages that they were fine and did not need to use a hearing aid; they believed that if they wore one, others would think that they were deaf. But this was a myth because when a person who was not able to hear conversed with a normal person, then the normal person would soon find out the truth.
Another myth about digital hearing aids was that an audiogram had to be conducted in a sound-proof room. But if one was going to wear the hearing -aid in a natural environment, the test in a sound-proof room would only yield an audiogram that would recommend a hearing aid suitable for a sound proof environment which was impossible n a city like Bombay.
Nearing the end of her presentation, Dr. Vora said that a good hearing aid improved the quality of life; people opted for knee replacements, whether or not these were successful, because there was improvement in their lives. A good hearing aid also improved the quality of life, removed a lot of miscommunications, improved one’s social life and made one more participative.
“I have noticed in my experience that in the long run, a person hard of hearing gradually loses confidence and also loses balance. In the last 12 to 15 months, for some reason I’ve had a lot of cases of younger people with symptoms of vertigo; they have been young, from 35 to 45 years old.
“Once you fit a hearing aid, they are fine. After all, it’s the inner layer, the cochlea, that is the seat for both balancing and hearing.
‘There is a direct link between hearing loss and vertigo’
“The sooner one goes to an audiologist, the better because the time required to adapt is much less. You must go to an audiologist who has more than one company’s instruments so that you have a choice… You must find out whether they (the audiologists) have a choice of two to three companies so that your audiogram is best fitted.”
Dr. Vora concluded by pointing out that this was her 35th year in the profession and she was offering free audiograms (costing from Rs. 500 to Rs. 1,000) to the members.
Answering questions, she told Suresh Jagtiani that a surgical procedure was required only in the case of cochlear implants (when the cochlea had stopped functioning).
But the candidacy for surgery was very important. Generally, it was performed on the congenitally deaf andseldom, if ever, on adults. Former Prime Minister I.K. Gujral’s brother architect Salish) had it done when he was 55 years old “and he went completely berserk”. He had to go to the US to have it removed.
As for the price, hearing aids cost from Rs. 4,000 to Rs. 2.50 lakhs per instrument. The price of advanced instruments could begin from Rs. 40,000. But many people offered discounts, free battery supply for two years and so on. This was pointless.
What was important was to check the number of channels against the price. What was the price of the product of company A and the number of channels it offered this could be compared with the price and the number of channels of another company’s product. If both had 6 channels, then they had similar sophistication. Companies that went for “marketing” also offered big discounts, but their prices were high to begin with .
PP Kalpana Munshi asked how one could clean one’s ears if one used a hearing aid.
Dr. Vora said there were three key points to remember:”Don’t drop it, don’t get it wet and don’t allow wax to enter it. Then you can keep it for ten years.”
Besides, it was best to take off the hearing aid when going to sleep. To clean the ears, one could use a solution.
Mudit Jain asked about the connection between hearing loss and vertigo
The guest speaker pointed out that the inner ear, the cochlea, had a tri-circled canal. This semi-circular canal was actually the seat of balance in the body.
“When you are not stimulating your inner ear, when you are not hearing, then slowly the functions become dormant and that’s exactly what happens when you wait (and don’t get a hearing aid). Your brain cells and your auditory cells, which are supposed to hear, also go dormant. You need to revive them; that is the time when you need to adapt, and adapt early.’ ”
Mudit also wondered about the condition in which people heard sounds in their ears.
Dr. Vora said that that was called tinnitus. Its cause and treatment were not known and one simply had to learn to live with it. If anyone offered medication for it, he wasn’t to be believed.
Finally, asked whether it was a good idea to have wax in the ears removed, she said that when ear-buds were used they actually pushed the wax right into the ear. If those with wet wax did not remove it, it could turn into a stone in the ear.
“You can use a solution called Solve or Wax all; fill your ear with it and let it remain for 20 or 30 minutes; it will dissolve all the wax. Then just dry your ear with cotton cloth,” Dr Vora added.