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Flashcards in 1 - Audiometry Deck (82)
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0
Q

Types of Audiometers

A

Diagnostic (Clinical) vs. Portable

Speech vs. Pure Tone

Manual vs. Automatic

1
Q

Audiometer

A

An electrical devise

Presents CONTROLLED acoustic signals

Tests some aspect of auditory function

2
Q

Clinical Audiometer

A

Desktop design

Allows clinicians to perform most audiometric tests

Consists of two channels so each ear can be tested seperately

3
Q

Portable Audiometer

A

Allows testing in almost any quiet environment

Depending on the model, it can perform only simple tests to a thorough audiological exam

4
Q

Where might portable audiometers be used?

A

Schools

Industrial Settings

Homes

Etc.

5
Q

Manual Audiometer

A

Examiner controls the presentation of the signal

The most common form of both portable & clinical audiometers

6
Q

Automatic Audiometer

A

Usually computerized

Programmed to present signals based on a specific response from the person (usually by pressing a button)

Commonly used in mobile testing vans that are set up to test multiple people at once

7
Q

Parts of Audiometers

5

A

Oscillator

Intensity Dial

Presentation Switch

Output transducers

Input signal selector

8
Q

What does the oscillator do on an audiometer? How does it work? Where is it?

(4)

A

Selects the frequency of a pure tone

Available at octave and mid-octave points between 125-8000 Hz.

Some can extend even higher

It is an internal component but there will be a dial or a switch on the panel

9
Q

What does the presentation switch do on an audiometer? How does it work?

A

Allows the examiner to present the signal to the patient

The length of time that the button is held down determines the length of the signal.

It is also called an “interrupter switch” because the tone can be set to play indefinitely until switch is re-pressed

10
Q

What does the intensity dial do on an audiometer? How does it work?

A

Controls the intensity

Usually ranges from -10 to 120 dB HL

The intensity can usually be modified in 5 dB steps

11
Q

Why can the highest and lowest frequencies on an audiometer not be played at the highest intensity setting?

A

It takes a large amount of energy to produce these tones

They come out distorted

12
Q

What does the output transducer do on an audiometer?

A

Coverts energy into a sound signal

13
Q

What are some types of output transducers?

A

Supra-Aural Earphones

Insert Earphones

Bone Oscillators

Speaker

14
Q

What are supra-aural earphones?

A

Standard headphones

Goes on top of pinna and ear canal

15
Q

What are insert earphones?

A

A long piece of tubing that is inserted into the ear canal via a soft, disposable tip

16
Q

What is a downside to supra-aural headphones?

A

They can collapse the ear canal due to pressure. Insert headphones can prevent this

17
Q

What are bone oscillators?

A

A small vibrator connected to a headband

It is usually placed on the mastoid bone behind the ear, but is sometimes used on the forehead

This sends a sound signal straight to the inner ear

18
Q

When are speakers normally used?

A

When testing infants or small children who are unwilling to use headphones

Can also be used to test the efficacy of hearing aids.

19
Q

What does the input signal selector do on an audiometer?

A

A set of switches use to choose whether the signal will be a pure tone, a speech signal, a noise, or a signal from an outside source.

On the clinical audiometer, this is often a separate set of controls but is incorporated into the frequency selector switch on portable units

This can also modulate pure tones creating a warbling sound

20
Q

Why is a warbling tone used?

A

It can help patients with short attention spans or with tinnitus

21
Q

Why must audiometers be calibrated?

4

A

To ensure the machine…

....produces tones at a specified level

....produces tones at a specified frequency

....presents the tone only to the correct earphone

....presents a tone free of distortion or unwanted noise interference
22
Q

Who regulates audiometer measurements?

A

ANSI

American National Standards Institute

23
Q

How often must audiometers be calibrated?

A

Once a year but should also be checked by the examiner prior to use

24
Q

When an examiner checks an audiometer prior to its use, what are they looking for?

A

An undistorted signal (Are cords undamaged?)

That the frequencies and intensities are accurate (can be done by performing a selftest of hearing)

25
Q

Most audiometric testing occurs at low levels to ____________.

A

Determine the threshold of hearing

26
Q

What do most audiology clinics use to perform testing?

A

A sound-treated test booth

This is not sound proof!

27
Q

What is the first step to an audiometric test?

A

To position the patient properly

- No distractions
- Unable to see examiner
- Where examiner can see patient
28
Q

What instructions are given to the patient prior to the testing?

(7)

A

The purpose of the test is find the faintest sound you can hear

Sit quietly without talking

Respond whenever you think you hear the tone, even if it’s quiet

It’s important to respond quickly when you hear the tone and/or when the tone stops

Each ear will be tested separately with tones of different pitches

Drinking, eating, chewing, smoking, etc. will interfere with the test

Any questions?

29
Q

When placing earphones, be sure to _________________ and that ____________.

A

Remove hats, headbands, glasses, etc.

Earphones are directly over the ears

30
Q

Which ear is normally tested first?

A

The better ear

If unknown, then the right

31
Q

How is the initial test performed?

A

Starts at 1000 Hz.

Then performs the higher frequencies: 2000, 4000, & 8000 Hz

Retesting of 1000 Hz

Then the lower frequencies: 500, & 250 Hz.

125 Hz is usually only reserved for those with severe to profound hearing loss

32
Q

If there is a 20 dB difference between octaves, then ___________.

A

The mid-octaves should be tested to determine the slope with greater accuracy

33
Q

What other reasons are there to test the mid-octave frequencies?

A

Monitoring the effects of noise exposure

Improving the precision of technologically advanced hearing aids

34
Q

What happens after the patient has been given instruction, fitted with headphones, and given the first tone?

A

There should be a preparatory phase (familiarization) to insure that the patient understands what to do

This is done by dropping the test tone in 10 dB increments

35
Q

What is the “Down 10, Up 5” rule?

A

If the patient responds to a tone, the examiner will drop it 10 dB until there is no response

If the patient does no respond to a tone, then the examiner will raise the tone 5 dB until there is a response

36
Q

Why is the mastoid bone usually used for testing bone conduction?

A

It is close to the inner ear

37
Q

What are some hurdles to using the mastoid bone for testing bone conduction?

A

The shape of the bone and its ability to move creates inconsistency in device placement

38
Q

What is sensorineural sensitivity?

A

The sensitivity of the inner ear and auditory pathways

39
Q

Can you test each ear separately using bone conduction?

A

No. There is no way to separate one ear from the other

40
Q

What is the point of audiometry?

A

To answer the following questions:

Does the person hear at a normal level?

How well does the person understand speech presented a comfortable listening level?

41
Q

Audiometry can test hearing, but it can also help in _________.

A

Diagnosing medical problems or pathologies

42
Q

What are some pathologies of the ear that do not create hearing loss?

A

Vertigo

Tinnitus

43
Q

What is the purpose of tone audiometry?

A

To measure the hearing sensitivity in the range of frequencies most important in understanding human speech

44
Q

What frequency range is usually measured in an audiogram?

A

250-8000 Hz

45
Q

What frequency range is most important in understanding speech?

A

200 - 6000 Hz

46
Q

What does signal detection not tell us?

A

What the person actually heard

Was it a pure tone, distorted, a tapping sound, etc.

47
Q

What is the difference between screening and threshold audiometry?

A

Screening audiometry is designed to evaluate a large number of people in a short amount of time

Threshold audiometry looks at hearing sensitivity across the range of frequencies important for everyday communication

48
Q

What is the pathway for air conduction?

A

Outer Ear

Middle Ear

Inner Ear

Eight Cranial Nerve

Brainstem

Cortex

49
Q

What is the pathway for bone conduction?

A

Inner Ear

Eight Cranial Nerve

Brainstem

Cortex

50
Q

What are important considerations for threshold measures according to ASHA?

(5)

A

Tone Duration

Interval Between Tones

Level of First Tone Presented

Levels of Succeeding Tones

Definition of Threshold

51
Q

Why is the familiarization process at the beginning of a hearing test important?

A

It assures the patient knows what to do

52
Q

Are the procedures for performing a pure tone test different when using air conduction versus bone conduction?

A

No

53
Q

Which ear do you begin with?

A

The better ear

If unknown, it’s usually the right

54
Q

How long are tones presented?

A

1-2 seconds

55
Q

Why is it important to vary the time interval between signals?

A

Unpredictability leads to better accuracy

56
Q

The level of the first presentation of tone for threshold measurement should be ________ the level of the listeners response to the familiarization presentation

A

10 dB below

57
Q

How is threshold defined during a audiometric test?

A

It is the lowest level that is responded to with a minimum of three responses at the same level

58
Q

When should inter-octaves be tested?

A

When the thresholds between two octave differ by 20 dB or more

59
Q

What might create false positives?

A

The tester is using detectable intervals between signals

The patient may not understand what to do

60
Q

When are false negatives usually seen?

A

When there is an outside motivating factor like insurance money or military service

61
Q

What does a higher number on an audiometer mean?

A

There are more funcions

62
Q

What does ANSI stand for?

A

American National Standards Institute

63
Q

What does ANSI do?

A

Sets standards for many instruments and measures

64
Q

Are ANSI standards stagnate?

A

No, they are in a constant state of revision

New standards are issued or reaffirmed every 5 years

65
Q

Pure Tone Air Conduction can be performed using _____, _____, or _____.

A

Supra-Aural Earphones

Insert Earphones

Sound Field

66
Q

What are the benefits to insert earphones?

A

Prevent ear canal collapse

Increase interaural attenuation

Provide better attenuation of ambient noise

Are lighter and more comfortable

67
Q

Why test by bone conduction?

A

Helps determine…

...Site(s) of lesion

...Severity of loss

...Management
68
Q

What might happen if bone conduction tests were omitted?

A

Misdiagnosis and mistreatment of the problem

69
Q

What is the interaural attenuation for bone conduction? What does this mean?

A

0 dB

When performing a test by bone conduction, there is no way to tell what cochlea received the information (Right? Left? Both?)

70
Q

What is the Weber Test?

A

A bone conduction test of lateralization

You place vibrating tuning fork on the patient’s head and ask where they hear the tone

71
Q

What is the Air Bone Gap?

A

When Air Conduction Thresholds are significantly WORSE than Bone Conduction Thresholds

72
Q

The air-bone gap must be ______ than _____ to be deemed clinical significant

A

Greater

10 dB

73
Q

When do we see air bone gaps?

A

With mixed and conductive hearing loss

74
Q

Can Bone Conduction ever be worse than Air Conduction

A

No

75
Q

What is Ossicular Discontinuity?

A

When the ossicles do not connect

76
Q

When performing a bone conduction test, where can the bone oscillator be placed?

A

On the mastoid bone or on the forehead

77
Q

What are the advantages of using the forehead for bone conduction tests?

A

Less curvature of the skull at forehead

Tissue and bone are more consistant

78
Q

What are the disadvantages of using the forehead for bone conduction tests?

A

Harder to keep vibrator in place

More force is required to elicit a response (10-15 dB more intensity)

79
Q

What are the ASHA procedures for bone conduction tests?

4

A

The test ear is uncovered

The threshold search is the same as for air conduction

Frequencies are limited to 250 - 4000 Hz

When testing at lower frequencies (250 & 500 Hz), ambient noise must be low

80
Q

Whats the difference between Hearing Sensitivity versus Sensorineural Senstvity?

A

Hearing Sensitivity refers to someones ability to hear with their entire auditory system, a.k.a., “normal hearing”

Sensorineural Sensitivity refers to someones ability to process sound using just the cochlea and the neural system

81
Q

What is the interaction between SPL and HL?

A

0 dB HL at any given frequency corresponds physically to the appropriate zero reference SPL for that frequency (the SPL threshold measurement)

0 dB HL has a different SPL reference depending on the frequency being measured