A short presentation describing, very generally, the reasoning and methods used to evaluate hearing in neonates and older pediatric patients, up to 7 years of age. Slides compiled as part of medical school studies. Sources for all imagery and sources listed in references section where possible. I do not claim ownership of any images or graphics. Slides for educational purposes only, and should not replace clinical judgement. No monetary gain was made for this work.

1. from birth until 7 years old
Robert Ferris

2.  0.1-0.2% of newborns will have markedly
impaired hearing at birth.1,2
 Neonates and infants are, naturally,
nonverbal, and only have the most
rudimentary reactions to external stimuli.
However, communication skills, language etc.
begin to develop long before a parent might
notice signs of deafness.3
 Therefore, specific testing is required to
detect hearing impairment in this age group.
 Early detection of impairment has a
measurable beneficial effect on language
development in these patients.1

3.  Standard newborn hearing screening tests
may vary slightly between different countries,
but in general there are defined methods
employed in Universal Neonatal Hearing
Screening (UNHS).
 These typically involve exposing the infant to
a sound, and evaluating response, e.g. head
turning, startle.
 Many factors other than hearing can influence
a neonate’s reaction, so an abnormal
screening test result is followed by referral to
audiology for more in-depth testing.

4.  A small microphone and earphone are placed
in the baby’s ear, and sounds are played.
 In a child with normal anatomy, the echo of
this sound will reflect in the ear canal, and be
picked up by the microphone.
 Abnormal result may suggest physical
pathology, for example a cochlear deformity.4

5.  Performed on a sleeping child.
 Electrodes are placed on forehead and behind
each ear, and an earphone is placed in each
ear.
 Sounds are played at different pitches.
 Electrodes measure action potential evoked in
the brainstem, to determine if a central cause
is present.

6.  Children may be affected by hearing loss not
present/detected in infancy.
 Common signs include being slow to learn
new words, poor attention span and
reactivity, and poor academic progress
compared to peers.
 It is therefore important that hearing
screening still be performed on children,
particularly if symptoms appear.5

7.  Continuing evaluation should be done based on a
combination of
 Periodic checkups, and
 Clinical observation of the child
 A variety of tests can and should be employed, to
minimise error.
 Otoscopic examination should always be the first
step to help distinguish congenital from acquired
problems (e.g. otitis media, foreign body).
 Weber and Rinne tests are typically performed to
evaluate sensoineural and conductive conductive
hearing loss, respectively. These tests are easily
performed and require minimal equipment.

8.  Tympanometry may be used to assess the
mobility of the tympanic membrane
(contraindicated in conditions where middle ear
pressure is ↑).6
 Conditioned play audiometry involves
conditioning the child to perform a task each
time a sound is heard, and may be a useful tool
for assessment by incorporating elements of
play.7

9.  After the age of 5 years, congenital hearing
impairment has been either detected or ruled
out in almost all patients.
 Impairments at this age are usually caused by
acute issues. However, more uncommon
causes may still arise (e.g. acoustic neuroma).
 Children should still be observed for signs of
hearing impairment, and tested accordingly.
Periodic testing may also occur, though with
less frequency than in younger patients. After
7 years of age, these tests are almost never
indicated without clinical signs.
8

10. References:
1. Ptok, M. (2011), ‘Early Detection of Hearing Impairment in Newborns and infants’,
Deutsches Ärzteblatt International 108(25), 426-431
2. Thompson D., McPhillips H., Davis R., Lieu T., Homer C., Helfand M. (2001), ‘Universal
newborn hearing screening: summary of evidence’, JAMA 286 (16)
3. Guess, D. (1969), ‘A functional analysis of receptive language and productive speech:
acquisition of the plural morpheme’, Journal of Applied Behavior Analysis 2(1): 55–64
4. Robinette, M., Glattke, T. (2007), Otoacoustic Emissions: Clinical Applications. New
York: Thieme Medical Publishers Inc.
5. American Academy of Pediatrics, Committee on Practice and Ambulatory Medicine and
Bright Futures Steering Committee, (2007), ‘Recommendations for preventive pediatric
health care’, Pediatrics 120 (6):1376
6. British Society of Audiology (2013), ‘Recommended Procedure: Tympanometry -
Summary of the Clinical Practice Guideline’, British Society of Audiology 2-20
7. Children’s Hospital at Dartmouth-Hitchcock, ‘Hearing Tests for Children’, accessed at
[https://www.chadkids.org/audiology/audiology_hearing_tests.html] on 22/05/2019
8. Buz Harlor, Jr. A., Bower C., Committee on Practice and Ambulatory Medicine, the
Section on Otolaryngology–Head and Neck Surgery (2009), ‘Hearing Assessment in
Infants and Children: Recommendations Beyond Neonatal Screening’, Pediatrics 111(2):
436