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Degrees
of Hearing Impairment
For Children
Frequencies
in Hz
Normal Hearing
Children with thresholds
less than 15 dB HL have normal hearing. These children will be
able to hear vowels and consonants. Speech sounds will be heard
clearly and consistently. Children with normal hearing are able to
understand rapid speech better than a child with even a mild
hearing loss. These children are better equipped to understand
speech when background noise is present.
Mild Hearing Loss
Children with thresholds
15 dB HL – 30 dB HL have a mild hearing loss. Speech sounds are
not heard clearly and consistently. These children will be able to
hear the vowel sounds, a, e, i, o, u, clearly, but they may miss
some consonants. For example, they may miss the sounds p, h, f, s
and th. A mild hearing loss will make it difficult for a child to
understand speech, when background noise is present. Rapid speech
also poses a problem.
Moderate Hearing Loss
Children with thresholds
30 dB HL – 50 dB HL have a moderate hearing loss. Without the
amplification of hearing aids and implementation of auditory
training and speech therapy, these children will miss most sounds
at a normal conversation level. Due to inaccurately hearing sounds
and missing sounds completely, children with a moderate hearing
loss may have a limited vocabulary and difficulty with grammatical
rules, word placement in a sentence and word meanings.
Severe Hearing Loss
Children with thresholds
50 dB HL – 70 dB HL have a severe hearing loss. No sounds can be
heard at normal conversation level, without amplification by a
hearing aid. If a severe loss is not detected at birth, or shortly
there after, language and speech will not develop spontaneously
and learning dysfunction is possible. If a severe hearing loss is
identified early, and the child is fit with hearing aids and
auditory training and speech therapy are implemented, the child
has a much more positive outlook on speech and language
development and facility of learning.
Profound Hearing Loss
Children with thresholds
greater than 70 dB HL have a profound hearing impairment. Without
the use of hearing aids, these children, generally, are unable to
hear sound. Children with a profound hearing loss will experience
severely impeded language development and learning dysfunction.
The speech of these children is characterized by extended vowel
sounds, distortion of vowel sounds, slow speech, excessive
nasality and abnormal rhythm. Children with a profound hearing
loss are able to learn speech and language with the use of hearing
aids and intensive training and education.
Children with mild,
moderate, severe and profound hearing losses can all benefit from
the use of hearing aids, auditory training and speech therapy. The
type of hearing aid and intensity of auditory training and speech
therapy can be determined by an Audiologist and Speech Language
Pathologist, based on each child’s hearing loss and special
needs.

A Trip to the Audiologist
Here are a few things that
can be expected at a visit with an Audiologist. First, the
Audiologist will request information about the child including
medical history and overall development, speech and language
development and the parents’ observations and concerns regarding
the child’s hearing.
If the child is between
birth and two years of age, the Audiologist will begin testing
with Behavioral Observation Audiometry (BOA). With BOA, the
Audiologist observes the child’s unconditioned responses, such
as head and/or eye movement, in response to sounds produced by
noisemakers and soundfield signals, in a controlled environment.
Testing usually begins in
the soundbooth for children two and older, where several tests are
performed in order to obtain an accurate measure of the child’s
hearing thresholds at different frequencies. The following are
tests the could be performed:
- Speech
Reception Threshold (SRT) – The audiologist tries to find
the softest test sound level at which the child is able to
identify 50% of spoken words.
- Audiometry
- The child wears a set of earphones and is asked to respond,
when he or she detects a sound generated by an audiometer. The
audiologist will test different frequencies.
- Bone
Conduction – A bone conduction receiver is placed behind the
ear, and the
child is asked to respond when he or she detects a sound
produced by the device. The Audiologist will test different
frequencies.
The Audiologist will
examine the ear canal and tympanic membrane (ear drum), with an
otoscope, before continuing with immittance testing. The
immittance test battery includes the following tests:
- Tympanometry
– This test measures how easily sound flows through the
tympanic membrane (ear drum), while air pressure is varied
against it.
- Acoustic
Reflex Measurement – This test measures the contraction of
the middle ear muscles in response to loud sounds.
- Physical
Volume Measure
For
children who are physically or mentally incapable of cooperating
to perform the conventional audiometric tests, which require
participation, there are other tests, which measure the hearing
function of a child without his or her active participation.
After reviewing the
patient’s information and test results, the Audiologist will be
able to describe a hearing loss as unilateral (affecting one ear)
or bilateral (affecting both ears), the degree of hearing
impairment: mild, moderate, severe or profound, and the type of
loss: conductive, sensorineural or mixed. If he or she deems
necessary, the Audiologist will make referrals to other
professionals. He or she will make recommendations regarding
amplification and provide suggestions on how to best manage the
hearing impairment.
Contributed
by Brandi Pandis

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