Identifying hearing loss in infants

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According to Hema Thakor, client relations executive at Oticon South Africa, a hearing aid manufacturer, the gap between the vocabulary of children with normal hearing and those with hearing loss widens with age. "Without intervention, children with hearing loss may struggle to catch up and therefore it is important to act early if you suspect your child has a hearing loss. The earlier the problem is identified and intervention begun, the less profound the ultimate impact will be."

Infants are able to recognise familiar voices even before they are born, which is why babies get excited in the womb. "As a parent, you will expect your child to respond to your voice when you speak to them, or for them to move their head or eyes to follow the sounds they are hearing or to startle at loud sounds such as a door banging. However, if there is no such reaction then it would be prudent to investigate your child's hearing."

A mild hearing loss is often not picked up, as it is easy to miss that a child cannot hear soft sounds. It normally only becomes known once the child starts talking, between the ages of 1-2 years of age. A delay in language development is an indicator or once he or she starts school and struggles to hear well in the classroom.

If a parent suspects that a child has a hearing loss, they often do not know how to go about confirming it. "It can be quite a traumatic discovery and many parents spend quite some time in a state of denial, because they find it too painful to accept what is happening. It is a perfectly normal reaction, but for the sake of your child it is important to contact an audiologist and to have your child's hearing tested as soon as possible.

Causes of hearing loss

Hearing loss can occur if an infant:

• is born prematurely
  
• has stayed in the neonatal intensive care unit
  
• is given medications that can lead to hearing loss - ototoxic drugs such ARVs
  
• has a family history of childhood hearing loss
  
• has had complications at birth
  
• has had infections such as meningitis or cytomegalovirus
  
• is exposed to very loud sounds or noises even for a brief duration

A child's hearing can be tested as early as the day they are born. Many medical facilities in the private sector offer newborn hearing screening programmes that will test the child's hearing before he or she is discharged.

Simple tests

In an infant, the aim would be to test whether the ear is functioning correctly by objectively assessing the outer ear, middle ear and inner ear (cochlear), which means that the infant does not have to respond to the test but that the equipment utilised will determine the results. Recommended screening technologies include oto-acoustic emissions (OAE), which assess cochlear functioning and auditory brainstem responses (ABR), which record neural activity in response to sounds. The tests are accurate and take one to three minutes to perform and have the same sensation as simply putting a finger in the infant's ear.

"A hearing loss or the degree thereof is often not diagnosed during one assessment in infants. An audiologist will often repeat the same test twice or perform multiple tests to confirm results in order to ensure the reliability of the results."

There are various treatment options available, following an accurate diagnosis. "Speak to your doctor or audiologist about optimising the hearing that your child has, to develop his or her speech and language. This could result in your child being fitted with a hearing aid or cochlear implant. However, your audiologist will be best equipped to advise which is better suited to your child. Remember that the road to hearing is often thwarted with emotional distress, so don't embark upon the process alone, even parents need support," concludes Thakor.