Pediatric Hearing loss is one of the leading birth defects in humans, occurring in about five out of every 1,000 children worldwide.
Hearing loss or deafness in children is a disability that often goes undiagnosed because there are no physical problems, and it is not visible on the outside.
Children who are hearing impaired cannot identify themselves. Pediatric Hearing loss that goes undiagnosed can have many far-reaching consequences. Children who do not have the ability to hear will become mute in the future without the ability to speak.
Speech, communication, language learning, cognitive ability, and psycho-social development of children with hearing loss lag far behind other children of the same age. They will lag behind in their studies and become isolated from others in class and in their friend circles. Having to listen to the blame of not paying attention in the class and not listening will make them physically and mentally weak.
If identified at an early age and given proper treatment and rehabilitation, they can become as smart as other children.
What causes hearing loss in children?
Pediatric Hearing loss can be classified into three categories as follows
- Conductive deafness due to diseases of the external or middle ear,
- Sensorineural deafness caused by disease of the inner ear or auditory nerves (cochlear nerve).
- When the hearing loss have both conductive and sensory component, it is known as mixed deafness.
Depending on the severity of hearing loss these are further classified as mild, moderate, severe and profound.
Sensory neural deafness is more common in newborns and infants. But conductive deafness is more common in older children.
Hearing loss in newborns
Hearing loss in newborn babies can be due to many reasons. In forty-five percent of infants, it is difficult to find an exact cause. In the remaining children, the cause of hearing loss can be genetic defects, abnormalities in fetal development, or medical conditions that occur immediately after birth.
Hearing loss in older children
Conductive deafness is more common in older children. Conductive deafness in children can be caused by anything from an ear wax to an ear infection. In some children, frequent colds, nasal congestion, and overgrowth of adenoids and tonsils can also cause hearing loss.
When to be suspicious of pediatric hearing loss?
Hearing loss in newborns and young children is harder to understand and more challenging. In older children, hearing loss caused by pus from the ear may be more pronounced. But in these children, hearing loss may go undiagnosed when there is only fluid collection in the ear.
Hearing loss should be suspected if the child does not respond to normal sounds. An examination by an expert ENT doctor is mandatory for such children. Special hearing tests and other tests may be required as per the doctor’s orders.
What tests will be required?
If hearing loss is suspected, the first thing to do is to see a specialist ENT doctor. Appropriate tests like Otoscopy / Otomicroscopy / Otendoscopy, Behavior Audiometry (BOA), Pure Tone Audiometry (PTA), Tympanometry, Oto Acoustic Emission (OAE), Brain Stem Audiometry (BERA) are prescribed by the doctor depending on the child’s age, cooperation, intellectual development etc.
If hearing loss is detected in the above tests, further tests are needed depending on its type and severity. A CT scan of the head and brain, and an MRI, Functional MRI scan may also be performed.
Your doctor may also order nasal endoscopy, eye exams, blood tests, thyroid tests, ECG and echo of the heart, and abdominal scans to detect other diseases that may be associated with hearing loss. Sometimes, some children may also need genetic testing.
Do not delay treatment!
Treatment should start from the day hearing loss is identified. The type of treatment needed will depend on the child’s age, type and degree of hearing loss, and other related conditions and illnesses.
Hearing loss caused by ear wax, ear infections, etc. can be treated with medicine. If there is frequent fluid collection in the ear, a small tube called a grommet is put in the eardrum through a small operation. Along with this, if the child has excessive growth of the adenoid gland, a surgery called adenoidectomy will have to be done.
Persistent ear infections in some children are another cause of hearing loss. Such children are likely to have a permanent hole in the eardrum. This hole is less likely to close on its own. An operation called tympanoplasty can close the hole in the eardrum and improve hearing in such children.
Treatment for children with sensorineural deafness or severe hearing loss is quite different. As such children may have other co-morbidities, the treatment of these children may also require referral to paediatrics, genetics, cardiology, ophthalmology and orthopedic specialists. Along with them, the services of audiologist, speech therapist etc. are also essential. Parents and teachers can play a positive role in the rehabilitation of these children.
If the hearing loss cannot be improved by medication or the above-mentioned surgeries, the first step in treatment is to perform a hearing test in such children with the fitting of a hearing aid. Children can use hearing aids at any age from infancy. If the child is able to hear well with the hearing aid, the hearing will be checked again after a few days.
If the child’s hearing does not improve or the hearing worsens, cochlear implantation surgery can be done if the child’s age and other conditions are favorable.
What is cochlear implantation?
A cochlear implant or bionic ear is a hearing aid that is surgically implanted in the ear. It is a battery powered electronic device.
A portion of this is surgically implanted behind the ear, under the skin. The other part is attached behind the ear, outside the skin. The outer part picks up the sound through a microphone, amplifies it and transmits it to the inner unit. The unit inside converts these sound waves into electrical waves. These electrical waves directly stimulate the auditory nerve and thus enable hearing.
Today, cochlear implant surgery is successfully performed on children six months of age or older. The earlier this surgery is done, the better the benefits.
Do not assume that the child will speak immediately after the cochlear implant. After implantation, audio verbal therapy (speech therapy) should be given to the child for a long time from six months.
In the past, cochlear implantation treatment was inaccessible to the common man due to the high cost of the implant device. But many state governments today provide subsidies for cochlear implant surgery (eg the Shruti Tarangam scheme under the Kerala Social Security Department) for patients with pediatric hearing loss. Apart from this, Prime Minister’s financial assistance, Governor’s financial assistance etc. are also available for cochlear implant surgery.
Universal Hearing Screening
Early detection of hearing loss and appropriate treatment and rehabilitation can result in the best possible outcomes for children’s language development.
A hearing test as soon as possible after the child is born is essential. Today in most hospitals this test is done before discharge after delivery. A screening test called oto acoustic emission is usually done. It is a completely painless test that does not require the active participation of the baby. Not only that, but the test results will also be available within 3-5 minutes. Some hospitals also perform a more advanced brain stem audiometry test.
If the child fails the otoacoustic emission test, brainstem audiometry should be tested next. This should be done before the child is three months old.
If the child fails the brain stem audiometry test, the child should be treated before the age of six months.
All children in developed countries are subjected to a hearing test before being discharged from the hospital. This is called Universal Hearing Screening. But in developing countries like India, only at-risk children are tested for hearing. Many hospitals in rural areas do not do this due to parents’ ignorance or lack of testing facilities. As a result, more than half of children with hearing loss go unrecognized. It is a very good thing that universal screening program is going on in most of the hospitals in Kerala today, though not widely.
Hearing loss in children is a difficult disability to recognize. If the child has no hearing, the child will not speak. If identified early and given appropriate treatment, these children can become as smart as, or even better than, other children.