Aud clinical assessment exam Flashcards
1
Q
What are some key considerations when taking case history?
A
- Sudden, gradual or fluctuating loss
- When was change first noticed
- Can you hear in a group situation?
- How often does the particular sensation occur?
- Does anything trigger the sensation?
- Describe the sound (for tinnitus)
- Is it continuous or intermittent
- Loss of balance? Describe the feeling
- On any medication?
- Medical history
- Family history of hearing loss?
- Was it congenital, acquired, hereditary, childhood, early adulthood etc.
- Occupation
- exposure to noise
- Any amplification devices currently
- Ability to hear speech
- Any disabilities
- If child, ask about birth history/postnatal days
- Developmental milestones being met?
- Speech delay?
- Family history of speech and lang delay?
- Learning or behavioural concerns?
- Childhood illness?
2
Q
Which frequencies is PTA obtained for generally?
A
250, 500, 1000, 2000, 4000 and 8000 Hz
3
Q
How do you calculate the Pure Tone Average?
A
Average threshold of 500 Hz, 1 kHz and 2 kHz
4
Q
Define the degrees of hearing loss
A
< or equal to 25 = Normal, 26-40 = mild, 41 - 55 = Moderate, 56-70 = Moderately Severe, 71-90 = profound
5
Q
What tone should be used as a starting tone for people with potentially normal hearing?
A
30 dB
6
Q
If initial tone cannot be heard, what should the next tone be?
A
50 dB
7
Q
If the 50 dB tone cannot be heard, what is the next step?
A
To increase in 10dB steps until a response is obtained
8
Q
What is the Hughson Westlake Technique?
A
This is essentially a “Down 10 , Up 5 ” procedure– if a response is obtained, decrease the intensity of the tone by 10 dB; if a response is not obtained, increase the intensity by 5 dB
A threshold is the lowest hearing level at which responses occur in a series of ascending trials, with two out of three responses required at a single intensity level
9
Q
How would you instruct a patient for PTA?
A
You will hear a series of tones (whistles). I want you to press this button for me every time you hear a tone. I want to find out the softest sound you can hear. So press the button even if the tone is very, very soft. Do you have any questions before we start?”
10
Q
What are the key steps involved in PTA?
A
- Turn the audiometer on and allow 10 minutes for the audiometer to warm up.
- Perform a listening check of the audiometer (Why and how?)
- Perform otoscopic examination (If the patient has discharging ears, impacted wax, sore ears, or ear operation performed within 2 weeks, audiological assessment should not be performed).
- Seat the patient properly for testing (Why and how?).
- Instruct patient
- Place earphones properly. It is important that the centre of the earphone diaphragm is facing the concha (opening of the ear canal) on each side. Make sure that the red earphone is on the right ear.
- Test the better ear first.
- Present tones of 1-1.5 sec in duration. After the presentation of a tone, you should allow for at least 2-3 sec before you present the next tone. Vary the rhythm of your tone presentation (Why and how?)
- Test 1 kHz, then 2 kHz, 4 kHz and 8 kHz. Repeat at 1 kHz for a reliability check (difference in thresholds should normally differ by no more than 5 dB). Then test 500 Hz and 250 Hz.
- If there is a difference of 20 dB or more across the adjacent octave frequencies, you need to test at the half-octave frequency (e.g. 1.5 kHz, 3 kHz or 6 kHz) as well.(e.g., in ski-slope audiograms)
- Remember to give adequate positive reinforcement to the client. Try to look at the client rather than looking at the audiometer all the time.
11
Q
What are five extrinsic factors that may impact on PTA threshold measurement?
A
Extrinsic variables –
• physical environment (background noise, lighting, temperature etc)
• Equipment (e.g., calibration, h/p worn out, broken electric wires, poor contact at joints)
• Test methodology (methods other than the Hughson-Westlake procedure – e.g., guessing)
• Instructions (inadequate or poorly phrased)
• Inadequate reinforcement during test
12
Q
What are five intrinsic factors that may impact on PTA threshold measurement?
A
Intrinsic –
• neurophysiologic factors governing organic sensation
• internal noise linked with vascular, digestive and respiratory function
• listener’s motivation, intelligence, attention
• familiarity with the listening task
• listener’s understanding of test instruction (language barrier, misunderstanding etc.)
13
Q
What are 5 limitations of PTA?
A
- Results affected by noise (physiologic and ambient noise) – giving raised thresholds
- It requires a behavioural response. Hence, young children and difficult-to-test patients may not respond reliably to auditory stimuli.
- A client can deliberately exaggerate a hearing loss (e.g., in compensation cases).
- Only test at octave frequencies. Abnormal hearing at other frequencies are not tested.
- It requires a specific environment to test accurately (e.g. Sound proof booth/quiet room)
- Relies on calibrated and quality equipment
14
Q
What are four points relating to the test, re-test variability
A
• Threshold testing at any frequency varies from test to test.
• Variability is usually the smallest at 1 kHz, but greater at other frequencies.
• Variability is large at low frequencies (e.g., 0.25 kHz)
Reason: sound leaking through the gap between the skull and the earphones (and background noise getting in through the gap)(Kylin, 1960)
• Variability is large at high frequencies (e.g., 4 & 8 kHz)
Reason: standing waves are created which affect the intensity of the sound heard by the listener. A slight change in positioning of the headphone changes the intensity of sound (Hickling, 1966)
15
Q
Are high or low/mid frequency sounds more affected by standing waves?
A
High
16
Q
How regularly are audiometers calibrated?
A
Yearly
17
Q
What are the three mechanisms of Bone Conduction?
A
- Inertial stimulation
- Compressional stimulation
- Osseotympanic stimulation
18
Q
What is intertial stimulation?
A
- When the skull vibrates as a unit, the inertia of the ossicular chain causes it to lag behind.
- Relative movement between the footplate of the stapes and the oval window occurs. Thus, sound is transmitted into the cochlea as per air-conduction (AC) route.
- This mechanism is more important for low frequencies (e.g., 500 Hz).
19
Q
What is Compressional stimulation?
A
- Occurs when forces are transferred from the skull into the cochlear fluid (perilymph).
- Causes movement of the membranes of the oval and round windows to different extents (different stiffness), and the cochlear aqueduct, resulting in deformation of the basilar membrane and hence stimulation of the cochlea.
- This mechanism makes a greater contribution to the transmission of high frequency sounds (e.g., 4 kHz).
20
Q
What is Osseotympanic stimulation?
A
- Vibrations of the skull produce sound energy inside the ear canal. Part of the energy travels to the TM, middle ear and then the inner ear (via the regular air conduction route)[This energy transmission is known as osseotympanic stimulation.], while the remaining energy leaks out of the ear canal.
- The sound going through the TM into the middle ear and the inner ear is much reduced if there is a middle ear problem (conductive loss). Thus, osseotympanic stimulation does not work if a ME problem is present.
21
Q
What instructions would you give for BC?
A
“You will hear the same tones as before. I want you to press this button for me every time you hear a tone. I want to find out the softest sound you can hear. So press the button even if the tone is very, very soft. Do you have any questions?”
22
Q
Which frequencies are tested for BC?
A
500, 1000, 2000 and 4000 Hz
23
Q
Which ear is tested first in AC?
A
Better ear
24
Q
Which ear is tested first in BC?
A
Worse ear
25
What to do if reverse air bone gap found?
(1) re-test with careful attention to bone vibrator placement;
(2) check if test procedure (or instruction) is correct;
(3) check calibration of bone vibrator.
26
What are 7 factors affecting the validity of BC thresholds?
1. Variation in the size of the skull and thickness of the skin and bone of the skull affect the BC thresholds.
2. Maximum output of audiometer for BC is only 60-70 dB HL. So it can’t measure the AB gap correctly if the AC>70 dB.
3. With sound delivered through the bone vibrator, the whole skull is vibrating. The cochlea with better sensitivity will respond to the sound. So, it’s not possible to know which cochlea is responding unless an appropriate masking procedure is applied.
4. From a theoretical perspective, there is no energy loss for bone conducted sound to travel from one ear to the other. Hence, interaural attenuation for a bone conducted sound is taken as 0 dB {but it can vary from 0 – 10 dB in practice}.
5. Vibrotactile responses (vibrations) may occur for 500 Hz at about 55 dB HL. So, vibrotactile responses, marked by VT on the audiogram, should not be considered as true hearing responses.
6. Environmental noise affects the measurement of BC thresholds. Hence, BC thresholds are elevated when testing in non-sound treated rooms.
7. When conducting BC testing at the low frequencies (500 & 1000 Hz) with one ear occluded, the measured BC threshold may be better than the true BC threshold by 5 to 15 dB. This is called an Occlusion Effect.
27
What is Carhart Notch?
Carhart (1950) found that patients with otosclerosis (in the early stages) often show a dip in BC thresholds around 2000 Hz. This is often called a “Carhart Notch”.
28
How can ME disorder make BC thresholds worse?
BC thresholds are influenced by middle ear disorders because both inertial and osseotympanic modes of stimulation depend on the function of the middle ear to various extents.
29
What are the three rules of masking?
- If the bone conduction threshold of the better ear and the air conduction threshold of the test ear differ by 15dB or more, bone masking required
- If the bone conduction threshold of the non test ear and the air conduction threshold of the test ear differ by 40dB or more, air masking is required
- If the air conduction threshold of the test ear and the air conduction threshold of the not test ear differ by 40dB or more, air masking is required
30
What are the steps for bone masking?
1. Obtain and record the unmasked BC threshold with the bone vibrator on the mastoid of the test ear.
2. Select an initial amount of masking (+10 dB) for the NT ear (i.e. nontest air-conduction threshold plus 10 dB EM). This masking noise is presented via the headphone (or insert) to the NT ear.
3. Start at the unmasked threshold level of the test ear that you have previously established (as per Step 1) and present the tone through the bone vibrator to the test ear [Note: BC threshold will remain unchanged if the hearing loss is conductive; but BC threshold will change if hearing loss is sensory/neural.]
4. Each time the client responds to the pure tone signal presented to the test ear, increase the masking noise presented to the non-test ear by 10 dB.
5. Each time the client does not respond to the pure tone signal presented to the test ear, increase the signal in 5-dB steps until the client responds again.
[Kei (2015) called this : UP 10, UP 5 procedure for masking]
6. Continue the procedure until the masking noise can be increased over a 30 dB interval without producing a shift in the threshold level of the test ear (i.e. over a plateau of 30 dB). See Example 1 for details. [Some clinics use a plateau of 20 dB]
31
What are the instructions for air masking?
“This time I’ll put a rushing noise in your other ear. I want you to ignore this rushing noise and listen for the same tones as before. I want you to press this button every time you hear a tone. So press the button even if the tone is very, very soft. Do you have any questions?”
32
Why is the 30dB plateau used in masking?
(1) To safeguard errors due to calibration,
(2) To allow for patient’s variability in performance, and
(3) To allow for the occlusion effect when performing bone masking at low frequencies (i.e. 500 Hz and 1000 Hz).
33
What is Central Masking?
Central masking is a shift or worsening in
threshold of the test ear due to the introduction of masking noise in the nontest ear. This shift in threshold is mediated through the central nervous system.
• Thecentralmaskingshiftbeginstooccuratlow masking intensities and appears to increase slightly with increased masking (usually 5-10 dB; can be as high as 15 dB).
• Centralmaskingmay(ormaynot)occurduringthe masking procedure. Its occurrence is unpredictable.
34
How do you find the max masking level?
Mmax=BCt +IA
35
What is the masking dilemma?
Masking dilemma occurs when adequate masking cannot be achieved in the non-test ear without simultaneously producing overmasking.
• It occurs when the masking noise we put in already exceeds the maximum masking level (i.e., M > Mmax ), resulting in overmasking.
- occurs in bilateral conductive hearing loss
36
How do you calculate and individuals IA for air conduction?
Take the unmasked Air conduction for test ear and minus the AC/BC min of non test ear
37
Can you calculate the IA if the unmasked and masked AC threshold for the test ear are the same?
No, you can only estimate a range within which it might fall
38
What are the principles of tympanometry?
A sound (226 Hz pure tone at 85 dBSPL) is delivered to the ear when the pressure in the ear canal is varied from +200 daPa to 400 daPa. The sound reflected by the eardrum is measured and analysed.
39
What is Ear Canal Pressure?
The change in applied pressure inside the ear canal is measured with reference to the Atmospheric Pressure (e.g., how much greater or smaller than the Atm. Pressure). [Note: 1 daPa (decaPascal) = 10 Pascals]
40
What does 0daPa mean?
no difference in pressure between the ear canal pressure and Atm. pressure. When the air pressure inside the middle ear equals the pressure of the ear canal, the ear drum vibrates freely and a large portion of sound energy is transmitted into the middle ear system (
41
In an uncompensated tympanogram, what is starting value on the righthand side?
ECV
42
What is the peak compliance when tympanogram is uncompensated?
ECV + SC
43
In a compensated tympanogram, what is the starting value on the righthand side?
0
44
What is the peak compliance when tympanogram is compensated?
SC only
45
What are two limitations of tympanometry
ECV can overestimate the actual ear canal volume by about 40% (Shanks & Lilly, 1981)
• TPP can overestimate the actual middle ear pressure by as much as 100% (Hunter and
Sanford, 2015)
46
What is normal SC range for adults?
0.3 - 1.6 ml
47
What is normal TPP for adults?
-100 to 50
48
What two terms should you use when describing a tympanogram on a report?
Mobility and pressure
49
What is the normal SC range for children?
0.2 - 1.0 ml
50
What are the instructions that you would offer for tympanometry?
I’m going to do a test to check if your ear drums are moving normally. I’m going to put this probe at the entrance of your ear canal and you’ll hear a buzzing sound with a change of pressure. You don’t have to do anything this time. I just need you to sit still and relax.
Do you have any questions before we start?
51
What is the procedure for tympanometry?
* Otoscopy
* Select an appropriate tip size and put the tip properly on the probe
* Insert the tip into the ear canal while pulling the pinna backwards (for adults). Don’t screw the probe into the ear canal as this is not necessary and will only cause uncomfortable feelings.
* Make sure that the tip is not blocked by the ear canal wall of the patient
* A good seal is obtained if an increase in air pressure (of up to +200 daPa) is observed
* A seal can usually be obtained even if there is a perforation unless the Eustachian tube opens too easily to release the air pressure.
52
List some key uses for tympanometry
* As an alternative to bone conduction (e.g.,in masking dilemma);
* To help in the diagnosis of middle ear pathology;
* To check the stages in chronic middle ear pathology (e.g. type B to type C to type A or vice versa);
* To check if grommets are patent or blocked;
* To confirm TM perforation if present.
53
List some variables affecting tympanometry
* Drift in calibration of equipment - daily calibration, using a 2 cc cavity, is important.
* Direction of air pressure change affects tym results (SC, TPP etc). In clinical practice, prefer + to to reduce chance of a collapsed ear canal.
* Rate of pressure change - static compliance (SC) decreases as rate of pressure change increases.
* 226 Hz probe tone is suitable only for adults and children. For infants from 0 to 6 months of age, clinicians must use a 1000 Hz probe tone.
* Inadequate probe seal (poor stability of the probe) – SC decreases, TW increases
* Patient’s jaw movement – creates artefacts (spikes)
* Poor probe design results in inadequate probe seal and wax occluding the probe tip.
54
What is the Acoustic Stapedial Reflex?
The acoustic stapedial reflex is an acoustically evoked contraction of the stapedius muscles in both ears by a loud sound presented to either ear.
55
What are the principles of reflexometry?
A probe tone (226 Hz at 85 dBSPL) is continuously delivered to the ear.
The pressure in the ear canal is kept at TPP (the pressure at which maximum admittance occurred).
A loud sound (e.g. 1 kHz tone of ≥80 dB HL) of short duration (≈ 2 s) is presented to the ear.
This loud sound(e.g., a 1kHz tone stimulus) elicits a contraction of the muscles in both ears.
• When the stapedius muscle contracts, the stapes footplate is rocked laterally from the oval window. The ossicular chain and the TM are stiffened.
• When this happens, sound energy (the continuous 226 Hz probe tone) going to the middle ear is reduced. Hence, the admittance is reduced in response to the contraction of the muscle.
• In general, as the stimulus becomes louder, the admittance is reduced further.
56
What is the criteria for present ASR?
ASR is considered present (in adults and children) if a change in admittance of ≥ 0.02 mmho occurs.
57
What frequencies are ASR tested at?
0.5, 1, 2 and 4 kHz
58
What is the Acoustic Stapedial Reflex threshold?
The acoustic stapedial reflex threshold (ASRT) is the lowest intensity of an acoustic stimulus at which a minimal change in the middle ear admittance can be measured (or visually detected).
59
What happens if an increase in admittance is detected in ASR?
Often, an increase in admittance is considered as an artifact (esp. when testing adults). But if the change in admittance grows with increasing stimulus intensity, it may be considered as a true ASR response.
60
What does it mean to get a biphasic response for ASR?
When biphasic ASR occurs at onset, it is regarded as a normal reflex response. BUT if Biphasic ASR occurs at both reflex onset and offset
• This pattern regarded as abnormal ASR, is usually seen in early stage of otosclerosis, congenital stapes fixation, and osteogenesis imperfecta
61
What is the process for ASR?
1. Alert the patient that he/she will hear some loud sounds in the ear. Ask the patient to sit still for the test (without jaw movements or swallowing).
2. ASR should be measured with the ear canal pressure set to TPP (this is usually done by the equipment after doing tympanometry).
3. Start with 0.5 kHz and present acoustic signal at 80 dB HL for about 2 sec.
4. If no ASR response is detected, increase signal in 5 dB steps until an ASR is detected.
(i) If an ASR is detected, repeat at the same level to check for repeatability of the response; If the response is not repeatable, increase the level in steps of 5 dB (up to a maximum of 100 dB HL for normally hearing clients) to elicit an ASR. Then check for repeatability again.
Or (ii) If an ASR is detected, increase the stimulus by 5 dB to see if the reflex response grows with increasing intensity. If the response magnitude is greater with the 5 dB increase in stimulus, then the previous stimulus level represents the ASR threshold.
5. Repeat Steps 3 & 4 for other frequencies (1, 2 and 4 kHz).
6. For diagnostic purposes, both ipsilateral and contralateral ASRs for each ear should be obtained.
62
What is the normal range for ASRT?
Normal levels (Median value = 85 dB HL; Range = 70 – 100 dB HL) for adults
63
What are raised ASRT classified as?
• Raised levels (105–110dBHL)
64
Name three factors that will affect ASRT?
* Degree of loss in either ear
* Type of hearing loss in either ear (e.g., conductive, cochlear (sensory), or retrocochlear hearing loss)
* Facial nerve (stapedial muscle) function
65
What results will be absent for mild-mod conductive loss in ASR?
Probe effect for test ear and also when stimulus is in ear with conductive loss.
66
For SNL when will ASR start becoming absent?
In general, ASR is present for ears with a hearing loss up to about 70 dB HL. Results will be raised above 55dB
67
What is recruitment?
Recruitment is defined as an abnormal growth of loudness for acoustic signals at supra-threshold intensity levels.
68
Will mild to mod cochlear loss ASR be raised, normal or absent?
Normal and High end of normal (85-95)
69
Will severe to profound cochlear HL ASR be raised normal or absent?
A mix of absent and raised for stimulus effect
70
Will retrocochlear lesion with HL ASR be raised normal or absent?
absent
71
Does Bells Palsy exhibit the probe or stimulus effect?
Probe
72
What do ASR look like for intra-axial brainstem lesion?
Absent contra-laterally
73
What is the reflex decay test?
A test for abnormal adaptation of the auditory system (checking for retrocochlear lesion). Acoustic reflex decay test may be applied only when reflex is present.
• Reflex decay is determined by presenting the stimulus test tone at 10 dB above the acoustic reflex threshold for 10 seconds at 500 Hz and 1000 Hz separately.
Reflex decay occurs when the amplitude of the acoustic reflex declines by more than half of its initial magnitude in less than 10 sec under continuous pure tone stimulation at 500 Hz or 1 kHz.
74
What are the purposes of speech audiometry?
* to measure how well a listener can recognize speech sounds;
* to confirm the results of pure tone audiometry;
* to check for non-organic hearing loss;
* to check for retrocochlear lesions;
* to measure the outcomes of hearing aid evaluation.
75
In speech audiometry, how much larger is SPL than HL
20
76
How do you calculate starting stimulus for speech audiometry?
PTA + 30 dB HL
77
What points are you looking to obtain for PI function plot?
Max (at or close to 100%), one above 50 % and one below 50%
78
What level loss would a cochlear HL be to not reach 100 % max?
<50 dB HL
79
What result might be seen for PI function for retrocochlear lesion?
With a retrocochlear loss, the maximum score may be poorer than predicted and there is a possibility of rollover
80
What PI function may be seen for psydeuhypacusis?
Better results than PTA
81
What are the steps involved in calibration for speech audiometry?
* Calibration sound: a 1 kHz tone or NBN. While playing the calibration sound, adjust the VU meter on the audiometer to zero
* The words are recorded so that every word produces a peak at zero on the VU meter
* Hence the output of the pure tone will be 0 dB HL (or 20 dB SPL) (Hint: Roughly 0 dB HL for speech = 20 dB SPL for monaural hearing). This value will be used in the AUDL7821 Exam.
* If the NAL-AB words are used in a clinic, a correction factor of “5” may be applied.[i.e., 0 dB HL=15 dB SPL]
82
Describe the AB words test
Designed by Arthur Boothroyd (1968).
Characteristics
1. 15 lists, each of 10 words per list
2. Each word is of consonant-vowel-consonant (CVC) structure
3. Most frequently occurred words
4. No carrier phrase
5. Scored by phonemes, not by the word. E.g., “cat” has 3 phonemes /k/, /ǽ/, /t/. Hence, 30 test items for scoring.
6. Standardized on 5- and 6-year-old children in UK
8. A person with an average pure tone threshold of 0 dB HL has an SRT at 0 dB HL (or 20 dB SPL) and has a maximum score of 100 % at 30 dB HL (or 50 dB SPL)
9. Accuracy of discrimination threshold: 3 dB if three measurements at three different intensities are obtained for the PI function
10. If the maximum score is less than 80 %, the SRT is not used. Instead the half-peak level (HPL) should be used.
83
What happens if a maximum score of <80% occurs in speech audiometry?
The half-peak level (HPL) should be used.
84
What instructions would you use for speech audiometry (AB words)?
When you have prepared the equipment for speech audiometry, instruct your patient: e.g. “You will hear a man saying some words. I want you to repeat each word immediately after the man. Some of the words will be very soft. It is important to have a guess even if you are not too sure what the man says. Do you have any questions?”
85
What is the procedure for AB words?
Adjust the VU meter to zero for the calibration tone.
• Calculate the PTA (.5, 1 & 2 kHz) of the ear (or the average of .5 & 1 kHz for ski-slope losses) in dB HL. Then add 30 dB to the PTA to get the initial presentation level (dial reading) where maximum speech score will occur. Present speech at this intensity level (PTA+30 dB) to obtain a percentage score.
• If the intended maximum score is close to 100 %, decrease the presentation level by 15 dB and test again.
• Decrease the presentation level again by 15 dB and obtain a score below 50%. If the score is still above 50%, decrease the level by another 10-15 dB to obtain a score below 50%.
• Connect the points (at least 3) and obtain the SRT.
• The PI function so obtained should agree with the predicted curve (based on the PTA)[i.e., the SRT ≈ PTA] (If SRT differs from the PTA by >15 dB, this result suggests the possibility of pseudohypacusis, retrocochlear lesion, language deficiency or equipment failure.)
• When you suspect a retrocochlear lesion as evidenced by case history or basic audiological findings, you may check for a rollover effect.
• To check for a rollover effect, the presentation level is increased to 40 dB beyond the presentational level at which maximum performance (ABmax) occur (or up to a maximum intensity level of 90 dB HL or 110 dBSPL).
• The reason for the rollover testing is to stress the auditory system with loud speech. At this high presentation level (90 dB HL), a patient with a retrocochlear lesion may obtain a markedly poor score (ABmin).
86
What is the rollover ratio?
A rollover ratio, defined as
(ABmax - ABmin) ÷ ABmax ,
If the rollover ratio is
greater than 0.2, retrocochlear lesion is suspected.
87
How and why do you check for rollover in speech audio?
To check for a rollover effect, the presentation level is increased to 40 dB beyond the presentational level at which maximum performance (ABmax) occur (or up to a maximum intensity level of 90 dB HL or 110 dBSPL).
The reason for the rollover testing is to stress the auditory system with loud speech. At this high presentation level (90 dB HL), a patient with a retrocochlear lesion may obtain a markedly poor score (ABmin).
88
What is the range of comparison between 3FA and SRT?
In speech audiometry, the SRT (± 15 dB) to be consistent with PTA results.
89
When is speech masking required?
When the presentation level to the test ear (in dB dial) and the best pure tone bone conduction threshold of the nontest ear differ by 40 dB or more;
90
How do you calculate initial speech masking level?
Speech stimulus level + AB gap (max) of NT ear -40 (IA) + 10 (EM)
91
What is the Kendell Toy Test?
* intended for children 3 to 5 years old
* 3 lists each of 10 monosyllabic words which are represented by small toy replicas
* 5 additional items are used as distracters
* each word-list contains a range of the most common vowels, diphthongs and consonants
* e.g. Test 1: knife, bath, soap, car, bus, tin, boat, pig, brush, pipe (pin, duck, jar, comb, wheel)
* Speech items are presented live voice in free field.
* Tester covers the face and say “Show me the ...” at various stimulus levels from normal conversational level to soft levels (whispering).
* A sound level meter placed near the child’s ears records the stimulus level for each stimulus.
* Child to point to toy replicas in response.
* Speech score is calculated as a percentage correct at a certain stimulus level.
* If child gets ≥ 90% at about 40-45 dBA (with whispering), child should have near normal hearing in the high frequency region (2-6 kHz) in the better ear.
92
What is the difference between open vs closed set tests in speech audio?
* open set tests - listeners are often asked to repeat words / sentences or to write down the responses. Advantages/disadvantages ?
* closed set tests - listeners are required to choose the correct response out of a set of responses (e.g. multiple choice format). Advantages / disadvantages ?
93
What are some advantages/disadvantages of recorded speech stimuli?
* Advantages: can test each ear individually; speech signals can be standardized; intensity of speech signals can be carefully monitored; speech signals are repeatable; background noise may be reduced, hence a lower intensity level of the signal may be used.
* Disadvantages: presentation is not flexible (hence not suitable for young children); listening environment restricted to clinic only.
94
What are some advantages/disadvantages of live speech stimuli?
* Advantages: presentation of speech signal is flexible; listening environment appears to be more realistic;
* Disadvantages: speech signals are more variable with respect to the speech spectrum and intensity level; the lowest intensity level may be restricted; talker differences may affect test results; speech signals can’t be standardized; lipreading may occur.
95
What is the CID Everyday Sentence Test?
```
• Ten lists each of 10 sentences
• score by key words in a sentence e.g.
Open your window before you go to bed.
• contains 50 key words in each list
• Meaning of sentence is assumed in the responses, but not actually tested.
```
96
What are 5 other speech audio tests
• NU-CHIPS (Northwestern University - Children’s Perception of Speech),
• Modified Rhyme test
• California consonant test (for high
frequency consonants)
• Nonsense syllable test (not affected by meaning of speech stimuli)
•CID Everyday Sentence Test
97
What is PB-50 word list?
* Harvard Psychoacoustic Laboratory
* Revised version (Egan, 1948)
* Widely used in USA
* 24 lists of 50 words each
* Phonetic Balanced - the appearance of a sound in the list with respect to its proportion of occurrence in everyday speech (confined to first part of the word)
* Devised to meet the following criteria: monosyllabic words, equal average difficulty, equal range of difficulty and phonetic composition for each list, words in common usage.
* containsacarrierphrasee.g.“Youwillsay...”
* scoring based on whole word
* half-list (25words) may be used instead o fthe whole list
98
What are the problems with PB-50 word list?
problems in clinical use :(1) low reliability, (2) wide range of difficulty among individual test items, (3) unfamiliar words for some listeners.
99
What should a formal audiologist report contain?
* Report to source of referral-Otologists, GP, paediatricians, speech pathologists, psychologist, audiologists, teachers etc.
* Patient’s particulars - name, address, telephone, date of assessment, relevant case history
* Comprehensive results and interpretation: (1) pure tone audiometry (not in detail if a copy of the audiogram is attached), (2) immittance results (not in detail if a copy of the tympanogram & ASR results is attached), (3) speech audiometry results - e.g., consistency with audiogram, speech discrimination ability in quiet, and (4) results of other tests (e.g. reflex decay etc.).
* Summary of results - In summary, these results are consistent with .....(nature and degree of hearing loss).Case management
* Further testing using objective measures [e.g., otoacoustic emissions (OAEs), auditory steady- state response (ASSR), auditory brainstem response (ABR)]• Regular monitoring of hearing (retest) if hearing loss is present.
* Counselling regarding implications of hearing loss and its prevention.
* Referral to specialist (e.g., Diagnostic or Rehab audiologist, general practitioner, speech pathologist, occupational therapist)• Referral to Australian Hearing for hearing aid prescription and rehabilitation services for children and pensioners with sensorineural HL.
* Referral for cochlear implants when hearing aids are not helping
* Recommend hearing tactics, listening strategies and lipreading class.
* Recommend assistive listening devices (e.g., infrared headphone, alarm system (vibrator), flashing light door bell and telephone etc.)
* Educational intervention (e.g., referral for special education services; to be seated close to teacher in class)
100
How would you describe speech audiometry results for different scenarios?
Speech audiometry consistent with audiogram, showing excellent speech perception at amplified levels in quiet conditions.
Speech audiometry results improved with amplification and consistent with the pure tone audiogram.
101
When should you use 2FA for speech audiometry?
When the slope is very steep
102
When will reflexes be elevated and absent for cochlear loss?
elevated 55-70dB and absent 70 and above
