EARLY HEARING DETECTION AND INTERVENTION

EARLY HEARING DETECTION AND INTERVENTION

SCREENING

Screening programme are used to identify those individuals who have a particular disorder or group of disorder. When a person is affected by hearing impairment or hearing disorders. These are addressed by audiological screening programme. The term identification audiometery is used to refer screening or hearing impairment.

New Born Hearing Screening

Early hearing detection and intervention refer to the systematic identification of babies with hearing loss. A variety of approaches and techniques for identifying hearing loss in infants have been used over the years. In the broadest term these includes public awareness campaigns, high risk registers, screening programmes employing behavioural or psychological tests, often combined with the use of risk indicators.

Public Awareness Campaigns

The public awareness approach uses such methods as mass media campaigns, brouchers and checklist to educate the public about the danger and sign of hearing loss in children. Public awareness campaigns are valuable adjacent to hearing loss identification in general they are not effective themselves because there is great uncertainty who about actually receives and responds to these efforts and concern that many primary care health provider might tends to discount parental suspicions.

High risk registers

Another approach that has been used in early identification of hearing impaired babies involves determining whether the child meets any of several criteria associated with hearing loss. Infants identified with high risk register are then referred for evaluation. Risk indicators for congenital progressive and delayed onset hearing loss based on the JCIH (2007) position statement.

Screening Approaches

1. Behavioural screening

Behavioural screening involves presenting a stimulus to the child and watching for change in behaviour appropriate for her stage of development with new borns, this involves intense stimuli (typically 60dB SPL or more) evoke response such as startle response, an auropalpebral reflex or arosal from sleep.

Behavioural observations approaches are no longer use in neonatal screening because of several severe limitation that involves subjective judgement that are highly susceptible, false positive and false negative results and the use of high level stimuli presented from loud speakers, so that mild and moderate cannot be identified.

Psychological Screening

Psychological measures have become standard testing in neonatal hearing screening, the principle techniques are the Brain stem response (ABR), ASSR (Auditory Steady State Response), OAE (Otoacoustic Emission). These methods require more costly instrumentation than behavioural approaches.

The ABR is well established as a neonatal screening test and has impressive rates of sensitivity, specificity and reliability.

The EOAE shares excellent sensitivity with the ABR for detecting hearing loss infants.

The ABR can be used to screen for auditory neuropathy spectrum disorders where as the pre neural nature of OAE’s makes them inappropriate for this purpose.

Universal new born screening become more simpler, quicker and more efficient automated ABR. L

Principle of Effective Public Help Screening Programs

·         The condition to be detected by screening should be an important health problem. Congenital hearing loss is the most frequent, birth detect, affecting about three new borns per thousand.

·         Permanent hearing loss affects approx 1% of young children in industrialised nation and the incidence is probably higher.

·         There should be an accepted treatment for identified cases.

·         Facilities for diagnoses and treatment should be available.

·         There should be suitable screening test. Psychological screening test for hearing are sensitive, specific and relatively inexpensive.

·         Hearing screening test can be completed in less than 15 minutes per child, are painless and have no negative side effects.

·         The neonatal history of the condition should be understood because permanent hearing loss occur relatively frequent and consequences are so obvious.

·         Hearing screening and diagnosis are relatively inexpensive and there is now good evidence that the cost of identification and treatment is small.

·         Case finding should be continuing process is not a “once and for all” project.

(ASHA) Infant Guidelines

·         The screening protocol involves determining whether the child can be hear pure tone of 1k, 2k, and 4k Hz. Presented at a screening level of 20 dB HL.

·         Each ear is tested separately by air conduction.

·         Children who fail the rescreening should be referred for Audiological evaluation.

·         Screening are recommended when special circumstances or risk factor exist.

·         Hearing screening should took place are when a child initiates special educations, repeats  a grade, was absent for the last regularly scheduled screening.

The Risk factor indicating the needs foe Hearing Screening includes:-

·         Concern about the child’s hearing , speech and language or learning.

·         History of delayed or late onset of hearing loss in family .

·         Sign of syndrome that include hearing loss.

·         Exposure to ototoxic drugs.

·         Recurrent otitis media with effusion.

·         Sign of syndrome include hearing loss.

·         Exposure of potentially harmful noise level.

·         The children be referred for medical examination if any following condition are identified.

·         Drainage from the ear (otorrhea).

·         Ear canal anomalies of the ear that were not previously identified.

·         Ear structural anamalies.

·         Ear drum abnormalities or perforation.

National Goals for EHDI Programs

·         All new born will be screened for hearing loss before one month of age.

·         All infants who screen positive will have a diagnostic audiologic evaluation before 3 months of age.

·         All infants identified with hearing loss will receive appropriate early intervention services before 6 months of age.

·         All infants and children with late onset or progressive hearing loss will be identified at the earliest possible time.

·         All infants with hearing loss will have medical home as defined by American academy of paediatrics.

·         Every state will have an EHDI tracking and surveillance system that minimize loss to follow up.

·         Every state will have a system that monitor and evaluate the progress towards the EHDI goal and objectives.

Why early identification of hearing loss is important?

·         Early intervention of hearing loss can affect a child’s ability to develop speech, language and social skills.

·         Early identification help young children with hearing loss to learn language, skills and other communication skills.

·         Early intervention improves outcome for children development of cognitive, emotional and academic defects.

·         Early identification is important for better expressive vocabulary for better receptive and expressive language.

·         More improvement in speech/articulation skill who is having hearing loss.