Hearing Loss in Children

Dr. Ruchika Mittal

Blindness cuts off from things, but deafness cuts off from people.  Helen Keller

She also said: When one door of happiness closes, another opens, but often we look so long at the closed door that we do not see the one which has opened for us.

What is Hearing Loss?

Hearing impairment, hearing loss, or deafness, is a partial or total inability to hear. It is one of the most common medical conditions. The prevalence of childhood onset deafness (including all causes) is 2%. It is well recognized that hearing is critical to speech and language development, communication, and learning. Children with listening difficulties due to hearing loss continue to be an under identified and underserved population.

The earlier hearing loss occurs in a child's life, the more serious the effects on the child's development. Similarly, the earlier the problem is identified and intervention begun, the less serious the ultimate impact. Early detection and intervention can help the child to develop normal speech and language skills.

When describing hearing loss, we generally look at three categories: type of hearing loss, degree of hearing loss, and configuration of hearing loss. With children, it is especially important to diagnose and treat a hearing loss as early as possible. This limits its potential impact on learning and development.

Causes Of Hearing loss:

There are many reasons why a child can be born deaf or become deaf early in life. It is not always possible to identify the reason.

Causes before birth (pre-natal causes) 

Many children are born deaf because of a genetic reason. Deafness can be passed down in families even though there appears to be no family history of deafness. Sometimes the gene involved may cause additional disabilities or health problems. Deafness can also be caused by complications during pregnancy. Illnesses such as rubella, cytomegalovirus (CMV), toxoplasmosis and herpes can cause a child to be born deaf. There is also a range of medicines, known as ototoxic drugs, which can damage the hearing system of a baby before birth. 

Causes in infancy (post-natal causes)

There are number of reasons why a child may become deaf after they are born. Being born prematurely can increase the risk of being deaf or becoming deaf. Premature babies are often more prone to infections that can cause deafness. They may also be born with severe jaundice or experience a lack of oxygen at some point. Both of these can cause deafness.
In early childhood there is a range of things that can be responsible for a child becoming deaf. Infections like meningitis, measles and mumps can cause deafness. Ototoxic drugs, used to treat other types of infections in babies, can also be a cause. 

Self-Test for Hearing Loss

If you observe any of the following behaviours or symptoms of hearing loss, you should consider having your child’s hearing evaluated further by an audiologist:

1.       Your child is inconsistently responding to sound.

2.       Language and speech development is delayed.

3.       Speech is unclear.

4.       Volume is turned up high on electronic equipment (radio, TV, CD player, etc.).

5.       Your child does not follow directions.

6.       Your child often says, "Huh?"

7.       Your child does not respond when called.

Assessment

Hearing loss is confirmed using a battery of audiologic tests, with the specific tests and measures selected according to the age of the patient. However, in general, a comprehensive hearing assessment designed to confirm hearing loss usually includes a hearing history, physiological procedures, and behavioural procedures.

1.       Components of a Comprehensive Hearing Assessment and Hearing History

a.       General concern about hearing and communication

b.      Auditory behaviours (reacting to and recognizing sounds)

c.       History of ontological diseases and other risk factors for hearing loss

2.       Physiological procedures or acoustic admittance measurements

a.       Otoacoustic emissions (OAE)

b.      Auditory brainstem response (ABR)

c.       Middle ear muscle reflexes

d.      Tympanometry

3.       Behavioural audiometry testing

a.       Behavioural Observation Audiometry (BOA) 

b.      Visual Reinforcement Audiometry (VRA) 

c.       Conditioned Play Audiometry (CPA) 

d.      Speech Audiometry 

Treatment

There are a number of devices that can improve hearing in those who are hearing impaired or deaf or allow people with these conditions to manage better in their lives.

1.       Hearing aids amplify the incoming sound, improve hearing ability. They cannot restore normal hearing.

2.       Cochlear implant (CI) is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing. Cochlear implants enable sufficient hearing for better understanding of speech. Majority of the cochlear implant centres are in big cities due to the high cost of the device, surgery and post-implantation therapy.