Rajan Speech & Hearing Centre (RSHC) is now on an aggressive drive to test children for early deafness. Since hearing loss is a hidden disability, the Institute is keen to test the baby early only because the first year of life is critical to the development of normal speech and language.

Annually India reports over 4,000 babies born with hearing loss. Most babies born with hearing problems are otherwise healthy and have no family history of hearing loss. To ensure that the baby has normal hearing, it would be vital to test as early as possible, stated Krishna Kumar, audiologist and director, RSHC.

New born hearing screening is a simple test done with sophisticated instruments and babies sleep through the process, he added.

The hearing loss can be by birth or it can affect later due to occupational health hazards. It is easier to treat, if it is detected early. RSHC specializes in evaluating infants, young children and those children with special needs. There are two types of hearing screening tests: Otoacoustic Emissions (OAE) and Auditory Brainstem Response (ABR) which take only minutes to evaluate each ear.

OAE is measured directly with a miniature microphone and sent to a special computer to determine the hearing status. It tests the outer hair function of the cochlea. Normal hair cells create an emission in response to tone. Presence of the emission is consistent with normal outer hair cell function. When outer hair cell function is normal the child's ear is interpreted as functioning normal.

Only if the OAE is absent or abnormal, then ABR is recommended. It tests the infant's ability to hear soft sounds through miniature earphones and assesses the auditory function from the eight nerves. The click stimulus usually at 35 dbHL is delivered to the infant’s ear via small ear phones. A pass or refer response is determined .It can be used as an effective tool for screening infants younger than 6 months. In the follow up test, a further diagnostic ABR can be used to determine the degree of hearing loss and also the nature of the hearing loss, stated Kumar.

If hearing loss is confirmed, intervention programme with the involvement of the audiologist and the speech therapist is recommended before the first year of life as it would make a remarkable difference in the quality of speech and hearing. Current intervention processes are hearing aids and cochlear implants along with speech therapy and auditory training, according to Kumar.

Other reasons for  hearing loss are  noise pollution and prolonged use of ear phones.

For those with severe to profound nerve deafness, Cochlear Implants have now transformed the hearing as it replaces the deficient cochlea. It could be for a one year-old child or an adult with a profound hearing loss in both ears and does not  benefit from hearing aids.