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.
