Pure Tone Audiometry

Front 1

air conduction frequencies tested:

Back 1

125, 250, 500, 750, 1K, 1500, 2K, 3K, 4K, 6K, 8KHz. Usually start at 1000 Hz and test at octave intervals.

Front 2

air conduction intensities tested

Back 2

-10dB to 110-120 dBHL (lower intensities at the high and low extremes of frequency)

Front 3

bone conduction frequencies tested:

Back 3

250 to 4000 Hz

Front 4

bone conduction intensities

Back 4

70-80 dB

Front 5

parts of a pure tone audiometer

Back 5

on/off switch, output selecter (right vs. left, ac vs bc), frequency selector, hearing level dial (attenuator in dBHL), masking level dial, tone presentation bar (aka tone interrupter, makes sound come out)

Front 6

test environment

Back 6

ambient noise must be controlled. this is done through sound-treated rooms (double or single), earphone enclosures and insert earphones.

Front 7

threshold of hearing

Back 7

softest level at which tones can be heard at least half of the time (3 out of 6). rarely exactly 50% level, round up to the last place you had a response. also depends on psychological factors.

Front 8

important that patient understand

Back 8

respond even when tone is very soft

Front 9

adult responses

Back 9

CAT: conventional audiometric technique. hand raising, finger raising, vocal response (might desensitize cochlea)

Front 10

false negative

Back 10

heard tone, no response

Front 11

false positive

Back 11

no tone presented, but response made

Front 12

clinician's role

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written/oral instructions, positioning of patient (must not see clinician, right angle is best)

Front 13

air conduction audiometry

Back 13

specify the AMOUNT of hearing sensitivity at various frequencies. tells you degree but not cause of hearing loss.

Front 14

collapsing canals

Back 14

happens in elderly, ear canals get saggy and can close creating a greater hearing loss due to the pressure of the ear phones. avoided with insert headphones.

Front 15

ASHA recommends for AC

Back 15

tested better ear first (right ear if better is unknown), test 1KHz first, then 2K, 4K, 8K/then 1000, 500, 250, 125

Front 16

1KHz

Back 16

where hearing is most sensitive, middle of the speech frequencies. retest later for more reliability.

Front 17

test half octaves if

Back 17

greater than 20dB HL between adjacent octaves

Front 18

start testing at

Back 18

30 dB HL. no response: increase to 50db HL

Front 19

once you've gotten a response:

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response: decrease 10 dB, no response, increase 5 dB (plateau method) until 50% response level at softest sound

Front 20

screening

Back 20

patient either responds or not. no effort is made to discern the softest sounds that can be heard; practice can be given. tones 1000, 2000, 4000 Hz at 20dbHL to usually the right ear first. failure at any frequency to either ear=fail. kids can respond with conditioned play response. test at high frequencies because theyre lest susceptible to ambient noise. within scope of SLP.

Front 21

threshold measurement

Back 21

not for SLP. recorded on audiogram. frequency is always on abcissa (x), and intensity always on the ordinate (y)

Front 22

pure tone average (PTA)

Back 22

average of thresholds at 500, 1000, 2000 (unless it is sharply sloping, in which case you should use the lowest 2). gives us idea of hearing for speech. SRT will usually be within 8 dB above or below PTA. SRT much better=high freq HL. SRT must worse=central auditory processing problem.

Front 23

distortional bone conduction

Back 23

bones of the skull are set in motion=distortion of structures of hearing in cochlea=same electrochemical activity as in AC (how sound normally travels)

Front 24

inertial bone conduction

Back 24

as skull moves, ossicular chain lags behind due to inertia, causing footplate of stapes to move in oval windows as in AC

Front 25

bone conduction audiometry

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tells us where the problem is. starting point depends on where AC thresholds are. BC vibrator placed on forehead or mastoid, may be masked or unmasked

Front 26

osseotympanic bone conduction

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vibrating skull bones cause air in ear canal to vibrate, some vibrations escape from canal but some go further in the canal, causing TM to vibrate as in AC

Front 27

interaural attenuation rate for BC is theoretically...

Back 27

0dB

Front 28

occlusion effect

Back 28

when a normal ear is blocked up, the loudness of a BC tone increases. this is why both ears must be uncovered during routine BC audiometry. more of a concern for frequencies at 1000 and below.

Front 29

masking

Back 29

delivering a noise to the non-test ear to remove it from the test procedure whenever there is danger of cross0hearing

Front 30

white noise

Back 30

broadband with approximately equal intensity at each freq. least efficient. all audible freq at equal intensities.

Front 31

narrow band

Back 31

frequencies surrounding the test frequency: more efficient (most efficient when width is precisely determined) some tone quality to it. for bone conduction audiometry

Front 32

speech noise

Back 32

proportional representation of frequencies important in speech, used in speech audiometry

Front 33

air bone relationship

Back 33

SNHL: BC=AC
conductive/mixed: AC worse than BC. technically BC cannot be poorer than AC.

Front 34

Air-Bone Gap (ABG)

Back 34

The gap between better BC and poorer AC (conductive and mixed HL only)

Front 35

symmetrical

Back 35

hearing in ears is the same or only 5-10dB different (as opposed to non-symmetrical)

Front 36

handicapping effects of hearing loss in children

Back 36

small amount of HL are more significant in kids. add 5dB to each number to get the adult standards. when we report the degree of loss, we report in AC.

Front 37

speech audiometry

Back 37

how much louder do we need to make speech to make it just as loud for them as it is for someone else?

Front 38

monitored live voice

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(patient must be in separate room)
examiner speaks stimulus words through a mic while monitoring volume on VU meter

Front 39

prerecorded speech material

Back 39

allows standardized presentation, not as flexible as MLV. words come at given interval and there is standardized preparation

Front 40

patient responses in speech audiometry

Back 40

oral responses used most often
picture pointing for those with problems
written response only for certain tests

Front 41

examiner role

Back 41

must use clear, natural articulation. patient cannot see face.

Front 42

speech-threshold testing

Back 42

speech detection threshold (SDT/SAT)
and
speech recognition threshold (SRT/SRT)

Front 43

speech detection threshold

Back 43

lowest level in decibels at which a pateint can barely detect the presence of speech 50% of the time. doesnt need to be understood, just detected. results in dB HL. you bracket the threshold. easier than SRT (speech has to be louder to be understood than detected)

Front 44

speech recognition threshold

Back 44

lowest hearing level at which speech can be barely understood 50% of the time. patient must repeat word back. much more widely used. spondee words are used as stimuli (2 syllables, equally stressed) can be prerecorded.

Front 45

SRT procedures

Back 45

one spondee at 30db HL
no response, increase t 50 db HL. no response, increase 10 dB. correct response, lower intensity 10 db. then correct, raise 5 db. you dont have to hear all of the sounds in the word to know what the word is.

Front 46

doing both SRT and SDT

Back 46

malingering and legal cases. SRT will usually be within 12 dB of SDT.

Front 47

why spondees?

Back 47

steep performance-intensity function lends itself well to threshold measurement. can go from 0% to 100% performance with small increase in intensity. they are not as black and white as pure tones.

Front 48

most comfortable loudness (MCL)

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normal hearing: 40-55 dB SL (not about setting this on the attenuator, SL is sensation level).
measured with continuous discourse (important in hearing aid fitting). not about threshold.

Front 49

uncomfortable loudness level (UCL)

Back 49

very important in hearing aid fitting, can suggest the presence of loudness recruitment. we all have a ceiling in the same neighborhood, even deaf people. not related to hearing loss.

Front 50

loudness recruitment

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abnormal loudness growth often present in those with SNHL. SRT may be 76 dB HL and UCL is 96 dB HL which means 20 dB range of usable hearing. the most difficult people to fit with amplification.

Front 51

word recognition score (WRS)

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measures how clear speech is when it has been made loud enough/comfortable for the person with hearing loss (turning up the volume doesn't help the clarity of speech). 50 words, they get a percentage correct.

Front 52

word recognition score procedures

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tested using lists of words that are phonetically balanced (in proportion to their use in connected english discourse). NU test 6 or different list of 50 monosyllables (PBK used for children.)

Front 53

word intelligibility by picture identification (WIPI)

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picture pointing test. useful when speech of patient is a problem, can be used with children down to 3.5. usually start at 30 dB SL for normal and SNHL and 40 dB SL for conductives. multi-testing: try to find PB Max. often tested in noise. 25 words and they get a percentage

Front 54

PB Max

Back 54

their best performance in the best possible setting