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Chapter 1 Index
A. General Information
about the well child examination B. Nutrition Issues
C. Sleep Issues
D. Dental Issues
E. Anticipatory Guidance
F. Screening Tests |
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Hearing Screening in Children
Geneva Britt MS CCCA
Who Should be Screened?
- Routine screening: newborns: done routinely in 11 states; now
increasing in frequency. The benefit of picking up hearing problems early
(< 3 mos.), is that prognosis for speech and language development is
better. Also screen older children before entering school, teenage years.
- Children with delayed language: 12 mo old: no babbling; 18 month old:
no words; 24 mo old < 10 words; 30 month old <100 words.
- Positive family history of sensineural hearing loss (most common cause
of sensi-neural loss)
- Anytime parent feels that there might be a problem.
- Prematures - 2-4% abnormal = half of all with hearing problems vs 2
per 1000 overall)
- Any child who has had bacterial meningitis or who would be on the high
risk registry.
- Chronic otitis media, serous otitis, congestion, excess cerumen (most
common conductive loss)
What is normal hearing and it what frequencies do we hear?
Audiologists consider 15 db to be normal in children (25db in
adults). Many of our handheld audiometers start testing at 20 db, however.
Speech range frequencies are between 250 Hz and 8000 Hz. In the 2000-4000
Hz range, such sounds as s/sh/th are present. While most speech is between
250 and 2000 Hz, higher frequency loss can affect speech as well.
Screening Tests that can be Utilized in Pediatrics
1. OAE (Oto-acoustic emissions test): Test used for newborn
screening. Easy to perform and inexpensive. 98-99% of children evoke a
cochlear response with this test. Two types of instruments: DPOAE
(distortion product) and TEOAE (Transient evoked). Problem is that any
problem in the middle ear - fluid, infection, vernix, cerumen, etc,
interferes with this test.
2. ABR (Auditory Brain Stem Response): the gold standard of
hearing tests; it is essentially “an EKG of the VIII nerve”; there are 4
intensities tested: 35 db, 55 db, 70db and 90db:
- 35 db: normal. Problem with this test: child must be still, so that
any baby over 6 months old must be sedated.
- 55 db: hearing aids often needed.
- 75 db: cochlear implants can be utilized but goal is not necessarily
to have good hearing, but to be able to hear different noises.
3. Behavioral Testing: Method used varies with age:
behavioral observation audiometry: < 5 mos old; visual reinforcement
audiometry (between 5-6 mos and 2 1/2 years old): animated reinforcer, play
audiometry (2 1/2 to 5 yrs): blocks in bucket etc.
4. Physiological Testing: Also a number of different types
of tests in this category:
- Hand-held audiometer (most children over 3˝ - 4 yrs. can do this test)
- Audiogram: headphones are used. Basis of this test is to compare bone
conduction to air conduction of sounds.
- Others: Speech reception threshold, speech discrimination - used by
audiologists.
5. Impedance Testing: not a test of hearing, but of
presence of fluid in the middle ear.
Normal peaked curve: A; flat curve: B; flat curve with increased ear
canal volume: patent tubes; negative pressure curve: C.
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