Objective Type hearing test, behavioral test of hearing, Pure tone Audiometry,Speech Audiometry, Tympanometry

1. Procedure of Hearing Assessment
1. Objective Tests of Hearing
2. Behavioural Tests of Hearing
3. Pure Tone Audiometry
4. Speech Audiometry
5. Tympanometry
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2. 1. Objectives Type
Tests
2

3. Objective Hearing Tests
 An objective hearing test is useful in identifying
damage to the inner ear and assessing your quality of
hearing. Objective hearing tests do not require your
cooperation and are typically performed on newborns
and infants.
3

4. Objective Hearing Tests include:
1. Otoacoustic Emission (OAE),
2. Auditory Brainstem Response(ABR)
OR
Brainstem Evoked Response Audiometry (BERA)
3. Auditory Steady State Response Test(ASSR)
4. Electrocochleagraphy
5. Middle Ear Test
 Acoustic Reflex Test,
 Static Acoustic Measures
 Tympanometry.
4

5. 1. Otoacoustic Emission (OAE)
 Oto= Ear,
 Acoustic=Sound,
 Emission= Coming out
 “Objective test”
So:
 Oto acoustic Emissions are sounds that are produced
by Healthy ears (in the cochlea) in response to acoustic
stimulation.
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6.  Otoacoustic emissions (OAE’s) are low level, inaudible
sounds produced by the outer hair cells of the inner
ear (cochlea). OAE’s can either occur spontaneously
or in response to clicks or tones. When the hair cells
of the inner ear are stimulated, they respond by
sending information to the brain and by sending an
“echo” back to the outer ear. This “echo” can be
analyzed and recorded. OAE’s are usually present in
individuals with a normal functioning cochlea but
may be absent if even a mild conductive or cochlear
hearing loss exists.
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7.  Last but not least, Otoacoustic Emissions, or sounds
given off by the inner ear when the cochlea is stimulated
by sound, are measured to narrow down types of hearing
loss.
 These emissions can be measured by inserting a small
probe into the ear canal.
 The probe measures the sounds produced by the
vibration of the outer hair cells, which occurs when the
cochlea is stimulated.
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8.  Otoacoustic emission (OAE) test to check the function of the
tiny hairs in the cochlea. The faint sound made by the hairs in
response to sound is called the otoacoustic emission
 A way to identify inner ear (cochlea) damage leading to a
hearing impairment is to perform an otoacoustic emissions
test. During this hearing evaluation, a doctor inserts a probe
that emits sounds into your ear canal.
 These sounds stimulate the inner ear, causing the outer hair
cells to vibrate. The doctor will use the probe to measure the
inner ear’s ability to produce the soft sounds created by the
vibration (emissions). If the inner ear does not produce
emissions, a hearing impairment may be present.
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9. 2. Auditory Brainstem Response
(ABR)or BERA
The auditory brainstem response test gives an
audiologist data about the inner ear and brain
pathways needed for hearing.
During the test, electrodes are placed on the
head to record brain wave activity.
To check the electrical activity in the brain in
response to a sound. Electrodes are placed on
the head to measure the brain waves
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10.  An audiologist may perform this test to gain more
information about your hearing sensitivity.
 The audiologist places a few electrodes on your head,
which will measure how the hearing nerves respond to the
sounds made through earphones.
 The information travels from the electrodes to a computer
that will record the results.
 The audiologist will review the data and look for the
softest intensity in a specific frequency range at which
your hearing nerves respond.
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11.  During this test, three small electrodes are placed on the
baby’s head, and then clicks or tones are played into little
headphones placed over the baby’s ears.
 The equipment measures the brain’s response to these
sounds.
 This test does not measure what the baby can hear, rather
it determines the sounds to which the brain actively
responds.
 This test takes only a few minutes and can be done while
the baby is sleeping.
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12.  Should hearing impairment be suspected in the auditory
nerve or even in deeper areas of the brain the doctor will
recommend BERA.
 For brain stem audiometry, an acoustic stimulus is supplied.
Head-mounted electrodes measure the electrical impulses of
the auditory nerve. Abnormalities shown give an indirect
indication of a possible disease of the auditory pathways in
the brain.
 This test also serves as evidence of other neurological
diseases, that may result in a loss of hearing.

13. 3. Auditory Steady State
Response (ASSR)
 Auditory Steady State Response (ASSR) is an objective test
used for evaluation of hearing ability in children too young for
traditional audiometric testing.
 Most children are referred for ASSR after a newborn hearing
screen in the hospital indicates the possibility of hearing loss.
 Early intervention strategies, such as hearing devices or
cochlear implantation, are necessary for development of speech
and language skills in a child with hearing impairment.
 The results obtained from ASSR testing can be used to
estimate the behavioral pure-tone audiogram.
 This information is essential in the management of children
with hearing loss
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14.  The brain activity is recorded using electrodes taped
on the forehead and behind each ear.
 The use of electrodes eliminates the need for active
participation of the patient (i.e., pushing a response
button every time a tone is activated).
 The results are detected objectively using statistical
formulas that determine the presence or absence of a
true response.
 Similar to traditional audiometric testing, threshold is
determined as the lowest level at each frequency at
which a response is present.
 ASSR provides an accurate, frequency-specific estimate
of the behavioral pure-tone audiogram.
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15.  The person being tested must be very quiet and still in
order to obtain reliable ASSR results.
 Often, testing is performed under sedation or in
natural sleep if the person is under 6 months of age.
 Results are obtained by measuring brain activity while
the person listens to tones of varying frequency
(pitch) and intensity (loudness).
 An audiologist may perform this test to gain more
information about your hearing sensitivity.
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16. 4. Electrocochleography
(Ecochg)
 The electrocochleography test is an objective measure of
the electrical potentials generated in the inner ear as a
result of sound stimulation.
 This test is most often used to determine if the inner ear
(cochlea) has an excessive amount of fluid pressure.
 Excessive fluid pressure in the cochlea can cause
symptoms such as hearing loss, aural fullness, dizziness,
and/or tinnitus.
 These symptoms are sometimes indicative of certain ear
pathologies such as Meniere’s disease or endolymphatic
hydrops.
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17.  The Ecochg takes up to 40 minutes to complete.
 A patient undergoing an Ecochg test will have several
surface electrodes placed on their head.
 A tiny microphone and an earphone will then be inserted
into the canal of the test ear.
 The patient will be instructed to relax while they listen to
a clicking sound.
 It is very important that the patient be relaxed for this test,
since any tension or muscle movement can slow down the
averaging process.
.
17

18.  No response from the patient is required for this test.
 While the patient is listening to the clicking, the audiologist
will measure the Ecochg response with a computer that
uses signal filtering and averaging to isolate neural activity
from the cochlea.
 The audiologist will collect several responses from the ear
and will look for the presence of a large waveform which
contains two components: the summating potential (SP)
and the action potential (AP).
 Both of these waveform components are direct results of
providing sound stimulation to the cochlea. A calculation of
the SP/AP ratio is made. An increased SP/AP ratio can
indicate excessive fluid pressure in the ear.
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19. 5. Middle Ear Test
 To determine how the middle ear is functioning, an
audiologist will get measurements such as,
acoustic reflex measures
static acoustic measures
 tympanometry
 During a middle ear test, the audiologist pushes air
pressure into the canal, causing the eardrum to vibrate
back and forth.
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20. Impedance Testing
 These are tests which determine the functioning of the
middle ear. It only takes from 3 to 30 seconds per ear. It
may also be referred to as Immittance Testing, which
includes tests called
 (a) Acoustic Reflexes.
 (b)Tympanometry, and
 In this type of evaluation, eardrum mobility is
measured under different pressure conditions to
determine if any problems exist in the middle ear.
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21. a. Acoustic Reflex Measures
 Acoustic reflex measures provide information regarding the
location of the hearing issue.
 Acoustic reflex is the contraction of the middle ear when
introduced to a loud sound.
 Testing for acoustic measure enables an audiologist to identify
a perforated eardrum and check the opening of the ear’s
ventilation tubes.
 An acoustic reflex test locates the possible location of a
hearing impairment.
 This hearing test uses sounds to determine if an acoustic reflex
is working properly.
 Depending on the loudness of the sound and your acoustic
reflex (or lack of acoustic reflex), the audiologist will be able
to assess the severity of your hearing loss.
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22. b. Static Acoustic Measures
 This test measures how much air is in the ear canal.
 This test helps show if there is a hole in the eardrum.
 Some people have tubes put in their eardrums to help stop
ear infections and hearing loss.
 It can also tell if you have fluid behind your eardrum.
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23. c. Stapedius Reflex Test
 In this test the ear is subjected to a loud noise.
 In healthy ears it results in the contraction of both middle
ear muscles that leads to a stiffening of the eardrum.
 This tension can be measured and an unexpected value
can indicate damage to the middle ear.
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24. d. Tympanometery
 Tympanometry was invented by Terkildsen and
Scott-Nielson in the form of an electroacoustic
device that measured the admittance of the human
ear across a range of sound pressures introduced
into the sealed outer ear canal by a pressure
pump.
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25. Tympanometery
 Tympanometry is an objective, physiological measure of
acoustic admittance of the middle ear as a function of air
pressure in a sealed ear canal.
 To obtain a tympanogram, a calibrated probe stimulus
(either pure tones or WB clicks) is presented to the outer
ear canal with a microphone.
 Air pressure in the ear canal is varied above and below
atmospheric (ambient) pressure, which causes the TM and
ossicular chain to stiffen.
 As the air pressure is increased or decreased in the ear
canal, the admittance flowing into the middle ear is
decreased, so more sound pressure remains in the ear canal.
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26. NORMAL Tympanogram / Type A)
 A normal tympanogram has a single clearly defined
peak occurring near atmospheric pressure
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27. TYPE B
 The most common
pathology that affects
tympanometry is fluid in
the middle ear space, or
otitis media with effusion
(OME).
 This condition results in an
increase in impedance
(decreased admittance),
 which broadens or flattens
the tympanogram
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28. Type c
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29. 29

30. Behavioral Audiometry
 The audiologist will be measuring your child’s
hearing levels for several different frequencies
(pitches) of sound. This will let the audiologist
generate your child’s audiogram, the overall
picture of your child’s hearing.
 School age children are generally able to raise
their hand or press a button when they hear the
tone.
 Hearing testing for younger children and children
with additional needs can require a little more
creativity. The audiologist will work with you to
figure out how your child can demonstrate his or
her best hearing.
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31. Types of Behavioral Tests
1. Behavioral Observation Audiometry (BOA)
2. Visual Reinforcement Audiometry (VRA)
3. Play Audiometry
4. Speech Recognition Test
31

32. 1. Behavioural Observation
Audiometry (BOA):
 BOA is a test used to observe
hearing behaviour to sound
when VRA is not possible.
 This is often used for infants
less than 6 months of age or
who are developmentally not
able to turn their head towards
a sound.
 Additional testing is often
necessary to supplement BOA.
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33. • Auditory signal presented to
an infant produces a change
in behaviour e.g alerting,
cessation of an activity or
widening of eyes.
 Moro`s reflex: sudden
movement of limbs
andextension of head in
response to sound of 80-90
dB.
 Cochleopalpebral
reflex: Child responds
by a blink to aloud
sound.
 Cessation reflex:
Infant stops activity or
starts crying in
response to a sound of
90 dB.
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34. 2. Visual Reinforcement
Audiometry (VRA)
 Visual reinforcement
audiometry (VRA) is a test
that allows an audiologist
to assess hearing in infants
and toddlers too young for
normal tests.
 VRA relies on behavioral
conditioning to train very
young kids to respond to
sounds. It is designed for
children aged 6 months to
around 2 to 3 years old
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35.  This test technique is suited
to infants aged 7 or 8 months
to 3 years developmentally.
 The child is taught (i.e.,
conditioned) to turn their
head. when a sound is heard.
 Initial conditioning is
achieved by the introduction
of stimuli at moderately
high levels
 When child looks for source
of sound they are shown a
colourful, moving puppet or
toy under illumination as a
reward.
 During the test, the child
will sit on mother’s lap or a
chair while sounds are
presented. The baby will be
taught to link the sound to a
visual reward such as a toy
or computer screen lighting
up.
 Once your child is able to
associate the sound and the
visual reward the volume
and pitch of the sound will
be varied to determine the
quietest sounds your child
is able to hear.
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36. 3. Play Audiometry
 Play audiometry is suited to
children aged around 3 to 7
year developmentally.
 The child is taught to respond,
using a pre-determined task,
whenever they hear tonal
stimuli that are introduced
through headphones or
through a bone conductor
placed behind the ear on the
mastoid.
 Given sufficient cooperation
from the child it is usually
possible to produce a
complete and accurate
"audiogram" that illustrates
their threshold of hearing for a
pre-determined frequency
range.
 During the test, sounds will be
played through headphones or
speakers and your child will be
asked to perform a simple task
when they hear the sound.
This may vary from putting a
ball in a bucket to completing
a puzzle.
 As with VRA, the volume and
pitch of the sound will be
varied to determine the
quietest sounds your child is
able to hear.
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37. Protocols
 Ages: Children who are
difficult to screen due to age or
developmental level
 Purpose: Obtain valid results
with very young children (ages
three to four years) or those
children who have difficulty
with standard pure tone
audiometric methods
 Description: A modification of
standard pure tone screening;
play audiometry
conditions the child to respond
to the sound by placing a toy in
a container, rather than raising
their hand
 Equipment :Pure tone
audiometer, stickers, and
small child-safe toys such as
animals, airplanes, cars,
clothes pins, nested boxes, or
pegs and pegboard
 Facilities: Appropriate size
table and chairs in a quiet,
comfortable setting with
limited distractions 37

38. Procedure
 1. First, practice without the headphones on.
 2. Lay headphones on the table, facing the child, with
audiometer set at 2000 Hz and maximum dB level to
ensure tone is audible.
 3. Hold the toy near your ear; assume a “listening”
attitude and present tone.
 4. Indicate through facial expression the sound was heard
and then drop the toy in a container, such as a pail; repeat
as often as necessary until the child shows interest.
 5. Offer the toy to the child and place your hand on theirs
to guide the first responses; encourage the child to wait
until they hear the sound.
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39.  6. When the child appears ready, present the sound and
guide the child’s hand to put the toy in the container.
 7. The child may give consistent responses after only one
demonstration or may need several demonstrations to
respond on their own.
 8. Once the child understands the play audiometry
technique use the audiometric procedure as described in
the pure tone audiometry screening section.
 9. Reward the child with praise after initial responses. If
this is not effective, a tangible reward like a sticker may
be given.
 10. If the child still is unable to do the screening after re-
instruction, stop and document “unable to screen.”
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40. Considerations
▪ The tone to response time varies between children; some
children will drop the toy as soon as they hear the tone;
others will wait until the sound goes off before dropping the
toy.
▪ If the child does not accept the headphones, the screener
should try putting them on for only one or two seconds,
removing and rewarding the child. Slowly increase the time
with the headphones on.
▪ A timid child will often benefit from watching other
children successfully complete the screening.
▪ If the child is cannot be screened, refer to Rescreen and
REFER.
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41. Play Audiometry
41

42. Speech Recognition Test
 The speech recognition test determines your
ability to both hear and understand normal
conversations. They measure the softest sound
that your ear can pick up and how clearly you
comprehend spoken words.
42

43. Procedure
 The speech recognition test
may be performed in either
silent or noisy environments,
depending on the specialist
and their analysis of your
hearing needs. Normally, one
ear is tested at a time – not
both at once.
 The test itself is very simple.
The specialist will probably
give you headphones and
present a series of words to
you,
each time varying the
loudness or intensity of the
speech.
 They will ask you to repeat
back the words. Generally,
a list of pre-selected words
are used for the test. Once
you are hearing correctly
only 50 percent of the time,
the test will end and
results will be determined.
43

44.  In this way, they will be able to determine at what
threshold of sound you can no longer understand
speech very well.
 Though simple, the test can be frustrating for some if
they experience a more severe hearing loss, as they will
not be able to hear or repeat most of the words.
44

45. Results
 In this way, they will be able to determine at
what threshold of sound you can no longer
understand speech very well.
 Though simple, the test can be frustrating for
some if they experience a more severe hearing
loss, as they will not be able to hear or repeat
most of the words.
45

46. 46

47. Introduction
 Pure tone audiometry is used to measure auditory
threshold of an individual
 The instrument used in this measurement is known as
the audiometer
 This is a subjective investigation, the accuracy of which
is dependent on the response of the patient
47

48. Audiometer
 This has been defined by
International Electrochemical
Commission 1976 as an
instrument used to measure the
acuity of hearing and auditory
threshold.
 There are two types of
audiometers: subjective and
objective ones.
 Pure tone audiometer – subjective
 Impedance / BERA - Objective
48

49. Clinical & Diagnostic Audiometer
49

50. Pure Tones
 Simplest of all sounds
 Specific and single frequency
 Described by their frequency, amplitude, phase and
duration
 Pure tone amplitude is quantified in decibel
 Pure tone audiometry provides information about the
type of hearing loss and also helps in quantifying
frequency specific threshold elevation.
 Increase in stiffness of middle ear causes low frequency
hearing loss, where as increase in mass effect of middle
ear causes high frequency hearing loss
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51. Features Of An Audiometer
 It generates pure tone
 Frequency of the tone generated can be selected
 Intensity of the tone generated can be selected
 It has the ability to route tonal stimuli to either ear
 Tone generated may be of intermittent /
continuous type. This is controlled by the presence
of an interrupter switch.
51

52. Components of an audiometer
 Oscillator
 Interrupter switch
 Equalization circuit
 Output power amplifier
 Hearing level attenuator
 Output transducers
52

53. Oscillator
Interrupter switch
 This generates pure tones
 Its accuracy ranges between
+/- 3% within the specified
frequency range
 Frequencies generated
include 125, 250, 500, 750,
1000, 1500, 2000, 3000,
4000, 6000, and 8000 Hz.
 These sounds are
electronically generated
 Tones should be either switched
on or off.
 Continuous tone undergoes
decay
 Patient fatigability should also
be considered
 It controls the duration of signal
presented to the patient
 It is typically in off position
when pure tones are presented
and can be turned on only on
pressing the button.
 It is typically in on position for
speech signal
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54. Equalization circuit
Output power
amplifier
 This contains resistors
which help in
equalization of sound
generated
 Human threshold for
various frequencies are
variable
 Human ear is highly
sensitive to 2Khz
frequency
 It is insensitive to high
and low frequencies.
 Signals produced by
oscillator needs to be
amplified.
 This amplifier produces
very little distortion.
 It has a good signal to
noise ratio.
54

55. Hearing level
attenuator
Output
transducers
 It controls the level of
signal from the
audiometer within
110-120 dB
 The intensity can be
varied in steps of 5
dB
 Attenuator steps
should be very
accurate
 Ear phones
 Bone vibrator
 Loud speaker
55

56. Head phones Bone vibrators
 These have a limited dynamic
frequency range
 At low frequencies vibrators
show distortions
 Pure tone bone conduction
thresholds can me measured
 Placed over mastoid process
(8-15 dB lower thresholds)
 Used to test pure tone Air
conduction thresholds
 These are supra-aural ear
phones
 Should always be calibrated
before use
 This type of supra aural ear
phones are easy to calibrate
 It has a flat frequency
response
 Delivers high output sounds
56

57. Loud speakers
 Used in free field audiometry
 Used to test infants and children
 Can be used to perform behavioral
audiometry
57

58. Calibration
 Used to define audiometric zero
 Calibration involves calibration of audiometer, ear
phones and bone vibrators
 Can be performed using human volunteers and
artificial ears
58

59. PTA
 An audiometer is an electronic device which produces
pure tones, intensity of which can be increased or
decreased in 5 dB steps.
 AC thresholds are measured for tones of
125,250,500,1K,2K,4K,8K Hz.
 BC thresholds are measured for tones of
250,500,1K,2K,4K Hz.
 It is charted in the form of a graph called audiogram.
59

60. Protocols
 Should be tested in sound proof room
 Claustrophobic patients should be handled with care
 Patients with collapsed ear canal should be tested using
special ear phones
 Malingerer’s should be tested only by an audiologist
 Patient should be seated comfortably
 Otoscopy should be done prior to audiometry
 Test procedure should be fully explained to the patient
 Glasses / ear rings should be removed
60

61. Precautions
 Patient should be visible to
the tester, and respond by
signaling.
 No visible or tactile clues
should be available to the
patient regarding the
hearing stimulus.
 Test should be conducted
in a sound proof room.
 Duration of presentation
should be 1-3 sec.
 The head phones should be
properly seated over the
external auditory canal.
 The audiometer should be
properly checked before
performing the test.
 Before placing the ear
phones on the patient, the
patient's ear should be
examined for the presence
of wax. If present it should
be cleaned.
61

62. Placement Of Head Phones
 Red head phone is placed over
right ear
 The diaphragm is placed over
ear canal
 It should fit snugly
 Head band should not be tight
62

63. Familiarization
 Testing is begun at 1000 Hz and 30 dB
 At this frequency the testee is likely to have residual
hearing. At this frequency testing retesting response is
reliable
 Testing usually begins with the examinee’s self
reported better ear, to decide whether masking is
necessary for testing the other ear
 Pulsed tone is used
63

64. Procedure
 Pure tone air conduction
threshold is tested using head
phones.
 “Up 5-down 10" method of
threshold estimation: This
technique is based on
Hughson - Westlake ascending
technique.
 Tones of short duration is
used for threshold estimation.
This method of threshold
estimation involves the
following steps:
 Step I : The better ear is tested
first in order to determine the
need for masking.
 Step II : Start with a 1000 Hz
tone at a level above the
threshold to allow easy
identification of the tone.
 If the patient is suspected to
be having a profound hearing
loss then the testing should
be started with 250Hz
frequency.
 This is because of the fact
that the individuals with
profound hearing loss often
have testable hearing only in
the low frequency range.
64

65.  Step III : The patient's
understanding of the listening
task should be checked by using
both short and long duration test
tones. The patient should be
instructed to raise the index
finger as soon as the sound is
heard.
Step IV : During testing, the
examiner should vary the interval
between tone presentations to
avoid telegraphing the stimulus.
 Step V : The starting intensity
of the test tone is reduced in
10 dB steps following each
positive response, until a
hearing threshold level is
reached at which the subject
fails to respond. Then, the tone
is raised by 5 dB until tone is
heard. The threshold is defined
as the faintest tone that can be
heard 50% or more of the time,
and is established after several
threshold crossings.
 Second ear is then test in the same way with the retest
beginning at 1K Hz.
 If there is difference in AC threshold exceeding 40dB at any
frequency masking should be used.
65

66. Hughson - Westlake ascending
technique Up 5 and down 10 method
 Tones of short duration is used
 Better ear is tested to decided whether masking is necessary
 Started at 1000 Hz at a level above threshold. This frequency is selected
because it is an important frequency
 In pts with profound hearing loss the test should be started with 250 Hz
because these patients have residual hearing only in low frequencies
 Stimulus is started at 0 dB and increased in steps of 10 dB till the patient
responds
 On positive response the volume is decreased by 10 dB. If the pt responds
it is decreased by 10 dB and repeated till he does not respond
 On no response the intensity is increased by 5 dB till the pt confirms
hearing the tone
 This should be repeated till the pt gives positive response in two out of
three attempts at the same dB level
 Tone presented should last between 1-3 seconds
66

67. 1K Hz
2
4250
500Hz
67

68. Bone Conduction
 Bone Conduction level are measured between 250Hz
and 4K Hz.
 BC is tested using a bone vibrator.
 The auditory threshold is assessed as described for air
conduction assessment. The only difference is that the
better hearing ear should be masked using a masking
tone delivered via a head phone.
68

69. Plotting Audiogram
 The readings are plotted
with Red color indicating
right side.
 The reading are plotted
with Blue color
indicating left side.
69

70. Audiogram Chart
Audiogram Keys
70

71. Environmental factors affecting reliability
 Excessive background noise
 Poor ventilation
 Poor lighting
 Invalid equipment calibration
71

72. Masking
Masking Principles of Masking
 If ABG (Difference between
A/C And B/C ) is greater
than 40dB then Masking is
needed.
 Masking is done in non test
ear(better ear) .
 Masking is a noise.
 It is process by which
threshold of audibility
raised by the presence of
an other sound.
 Rule 1
A/C need masking .A/C.
difference is greater than 40db.
 Rule 2
B/C needs masking ,A/C
And B/C difference is 15dbor
More
Rule 3
A/C needs masking ,ABG
(Air Bone Gap)is 40 dB.
72

74. Definition
 It is the test to measure the patient’s ability to hear and
understand and speech.
 It is the measurement of the acuity of hearing through
generation of tones of known frequencies and
amplitudes.
 It is also provides information regarding discomfort or
tolerance to speech stimuli.
74

75. Purpose Of Speech Audiometry
 To differentiate between organic and non-organic hearing
loss
 To measure the thresholds at which speech is clear
•Tells how loud it needs to be for speech understanding
•It provides additional information about the nature of the HL
•Role in decisions about and performance with amplification
•To differentiate between cochlear and retro-cochlear hearing loss
75

76. Common Speech Assessments
 Speech Reception Threshold (SRT)
 Word Recognition Score (WRS)
76

77. Speech Reception Threshold (SRT)
 Lowest level at which speech can be understood 50%
of the time
 Usually a very soft level (dB HL)
 Use spondaic word words lists (two syllable words)
 It is ear specific test
77

78. Spondee Words
 A spondee is a word with two syllables that both
pronounced with equal stress
 Use the VU meter to obtain equal syllabic stress
 Both syllables should peak at 0 VU if presented live
voice
 Also presented using recorded speech
78

79. SRT Procedure
 For SRT testing , the test level should begin twenty
decibels above the test ear pure tone average
 Same instructions pattern as determining thresholds
for tones
• Tell the patient: “you will hear some soft two-syllable words.
Please repeat the words as best as you can. if you’re not sure
of a word, please try to take a guess
Use the same bracketing techniques as pure tone
• If they repeat word correctly, decrease intensity by 10dB
• If they miss the word, increase intensity by 5dB
79

80. SRT-PTA Agreement
 The SRT decibel level results should be in a agreement
with the pure tone average threshold level obtained
during pure tone air conduction testing
 If there is poor SRT-PTA agreement, then the reliability
of results should be considered to be questionable
80

81. Roll Over Phenomenon
 It is seen in retro cochlear hearing loss
 With increase in speech intensity above a particular
level, the word score fall rather than maintain a
plateau as in cochlear type of hearing loss
81

82. Speech Audiogram
82

83. An Important Note on SRT
 Do not waste too much time on SRT
 As far as clinical utility is concerned, SRT is low on the
priority list
 Pure tone thresholds and WRS are much more
important
83

84. Word Recognition Testing
 Word or speech Recognition (Discrimination) score
 The percentage of phonetically balanced, monosyllabic
words that a patient can accurately repeat
 The intensity level used, should be the decibel level
identified during Most Comfortable Level (MCL) testing
 A pre-recorded list of 25 to 50 words should be
presented to each ear
 Each word should be preceded by a carrier phrase
• Say the word “pick”
• Say the word “Room”
84

85. WRS
 When scoring a patient’s performance on WR testing,
you must remember that wrong is wrong !
• -- The patient should only be given one attempt at
each word (oftentimes if they miss a word the first
time, they will ask you to repeat it….don’t)
• -- Close isn’t correct
i.e. if they say the word “eats” for “eat”
85

86. WRS In Determining Site Of Lesion
 Patient’s with normal hearing or conductive hearing
loss will perform normally on WR testing
 Patient’s with only high-frequency or a mild, flat SNHL
will also generally perform near normally
 The more severe the SNHL, the poorer a patient will
perform on WR testing
 Neural losses result in poor performance
86

87. Most Comfortable Level (MCL)
 The purpose of MCL testing is to establish a
comfortable intensity level for listening to speech
 The intensity level should be set twenty decibels above
the SRT
 It should be gradually increased to find the most
comfortable level
 The patient should be instructed to indicate whether
the “speech” is too soft, too loud, or comfortable
 Measurements should be made for each ear (
monaural) as well as both ear (binaural)
87

88. WRS Scoring
 90-100% Normal
 76-88% Slight difficulty
 60-74% Moderate difficulty
 40-58% poor
 < 40% Very poor
88

89. Recorded vs MLV Speech Stimuli
 Ideally, recorded word lists should be used when
performing speech audiometry
 If the clinician says the words while monitoring
his/her voice, it is to make sure they are peaking voice
at 0 on the VU meter, this is called a monitored-live
voice (MLV) presentation method
89

90. Limitations
 If the patient is not a native language speaker, you may
need to skip speech audiometry and note why didn’t
perform speech testing on the audiogram
 If you have hearing loss (as the tester) you may have
difficulty hearing what the patient said
• Don’t be afraid to ask the patient for clarification on a
word or to use the word in a sentence if you aren’t sure
what they said
• Have the patient face you so you can read their lips (just
make sure they can’t see your lips if you aren’t using a
recorded list)
90

91. 5. Tympanometry
91

92. 92

93. 93

94. 94

95. 95

96. 96

97. Procedure
 Probe is inserted into the external auditory canal till a
air tight seal is obtained.
 Probe tone is presented typically at 226Hz into the ear
canal while the air pressure of the canal is altered
between +200 and - 400 decapascals.
 The maximum compliance occurs when the pressure of
the external auditory canal and the middle ear
becomes equal.
 The compliance peak indicates the pressure of the
middle ear.
97

98. • The height of the compliance peak indicates the
mobility / stiffness of the tympanic membrane or the
middle ear cavity.
 By charting the compliance of tympano-ossicular
system various pressure changes different types of
tympanograms are obtained.
98

99. 99

100. 100

101. 101

102. 102

103. 103

104. 104