Balance and Pure Tone Testing Flashcards Preview

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Flashcards in Balance and Pure Tone Testing Deck (67)
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1
Q

Vestibular portion of the inner ear:

A
  • Semicircular canals

- Utricle and saccule

2
Q

Semicircular canals are needed for:

A

angular movement and body in space information

3
Q

Utricle and Saccule needed for:

A

linear movement and speed/direction

4
Q

Stereocilia Parts

A
  • Kincocilium
  • Sterocilia
  • Otolithic membrane
  • Cupula
5
Q

Kinocilium

A
  • longest hair cell at the top of the cell

- tubular with decreasing stiffness form bottom to top

6
Q

Sterocilia

A

-bundle of hair cells (similar to the hearing mechanism)

7
Q

Otolithic Membrane

A
  • gelatinous membrane in saccule and utricle

- contains otoconia (calcium carbonate crystals)

8
Q

Cupula

A

-Gelatinous membrane in semicircular canals

9
Q

Stereocilia Functions/uses

A
  • resting potential (firing rate)

- movement of stereocilia causes change in potential

10
Q

Stereocilia movement toward the kinocilium will:

A

Excite nerve

increase firing rate

11
Q

Stereocilia movement away from the kinocilium will:

A

inhibit the nerve

decrease the firing rate

12
Q

True or False

The vestibular system is tied to the visual system

A

True

13
Q

Vestibulo-ocular reflex:

A

-eyes move opposite of head turn or stay steady

14
Q

Saccade System

A

Quick return of the eyes to direction of head turn

15
Q

Smooth Pursuit

A

“tracking” an image with smooth eye movements

16
Q

Optokinetic system

A

combination of saccade and smooth pursuit

17
Q

Nystagmus

A
  • results from an abnormal neural connection between the vestibular and visual systems
  • can be symptomatic or benign
  • constant shifting of eyes
  • slow movement in one direction, fast return in opposite direction
18
Q

Electro-oculography

A

-electrodes placed around the eyes, measures eye movements while turning the head

19
Q

Proprioceptive/Somatosensory Kinesthesia

A

-info about posture, movement and body in space
-Supports balance via pressure sensors,
tactile cues,
muscular input (length, pressure, tension and noxious stimuli),
joint pressure, position and movement

20
Q

Balance Testing

A
  • symptoms can be acute or chronic (ENT visit first, mud history)
  • Rule out neurological or cardiac involvement (MRI or cranial nerve testing)
  • Determine peripheral vs central etiology (spontaneous or evoked nystagmus, Fernzel glasses prevent fixation)
21
Q

ENG/VNG

A

-electronystagmography or videonystagmography
1. electro-oculography tests the semicircular canals
2. Oculo-motor evaluation. Saccade, smooth pursuit, optokinetic and gaze fixation.
3. Dix Hallpike Maneuver
BPPV: benign paroxysmal positional vertigo
4. positional testing (9 positions and recordings)
5. Calorics (Warm/cool air or water interacts with the endolymph)

22
Q

What is the only balance test that evaluates the posterior canal?

A

Dix Hallpike Maneuver (BPPV)

23
Q

What is the only balance test that shows ear specific data on the horizontal canal and/or vestibular nerve?

A

-Calorics

24
Q

Explain Calorics

A
  • warm/cold air or water is introduced into the ear canal and reacts with the endolymph.
  • Heat makes the endolymph less dense and it moves cupula toward utricle
  • Cool makes the endolymph thick and dense which moves cupula away from the utricle
  • this creates a very dizzying effect
25
Q

Rotational Chair Testing

A
  • dark room
  • head attached/secured to chair
  • Record eye movements as chair moves
26
Q

Postural Control Testing

A
  • Assesses vestibular, ocular and proprioceptive systems
  • Floor sways/moves
  • patient is harnessed for safety
27
Q

Describe self rating scales and why they are useful

A
  • pre and post testing
  • patient perceives impact on their lives (functional psychological and physical)
  • used to quantify improvement after rehab services
28
Q

7 parts of Rehabilitation:

A
  • Home exercises
  • low sodium diet
  • Medication
  • Desensitization/habituation of vestibular responses
  • physical therapy to increase proprio-receptive system
  • Surgery
  • Vestibular Rehabilitation (increase central compensation)
29
Q

Pure Tone testing

A
  • Quantify auditory access to each frequency needed for speech perception
  • ear specific info
  • Helps us predict communication struggles (speech banana/articulation index)
  • Used to prescribe hearing aids, CI, etc.
30
Q

Audiometer

A
  • screening or diagnostic
  • Two channel allows for testing and masking
  • stimulus=puretone, live voice, recorded speech, noise, etc
  • Transducer=supra-aural headsets, inserts, speaker, bone oscillator
  • Routing=right, left, both
31
Q

Types of transducers:

A
  • Earphones (supra-aural)
  • Earphones (Circum-aural)
  • Insert earphones
  • Bone oscillator/Conductor
  • Speaker
32
Q

Earphones (Supra-aural)

A

Pros
-very easy to clean, -patient familiarity
Cons
-collapsed canal
-more crossover sound
(distance from earphone to eardrum can cause sound wave to cancel out)

33
Q

Earphones (Circum-aural)

A
Pros
-less constricting
-more comfortable 
Cons
-sound leaks around the headset
-less accurate results
34
Q

Insert Earphones

A
Pros
-reduces "turtle effect" in children
-no standing wave
-less masking needed
-no collapsed canals 
Cons 
-disposable and more costly 
-can't use if there is a drainage
35
Q

Bone Oscillator/Conductor

A

-Placement is important!
on mastoid bone but not touching pinna
-Pitfalls: may fall off easily

36
Q

Speaker

A

Pros
-can be used with difficult patients
Cons
-no ear specific info

37
Q

Attenuators of an Audiometer:

A

-Decibels: (-10 dBHL to 120 dBHL)
some only go to 110 dBHL
-Frequency (125-8000Hz)
some capable to go to 12,000

38
Q

Calibration of an Audiometer:

A
  • annual assessment

- computer based equipment is more stable than portable equipment

39
Q

Correction Factors for an Audiometer:

A
  • dBHL to add/subtract per frequency
  • sticker placed on audiometer
  • Can be different for each transducer
40
Q

Testing Environment:

A
  • quiet room for screening
  • diagnostic in sound treated room (NOT SOUND PROOF)
  • double walled booth with sound absorbing material with holes to expose this material
  • floor is carpeted with padding and raised above the ground to reduce vibrational noise
  • double doors with thick molding
  • windows are insulated
  • fire alarms only if sprinkler goes off it ruins material
  • special lights
  • quiet ventilation
41
Q

Pre Evaluation

A
  • File review
  • case history
  • self rating scales
  • conversation
  • Otoscopy
42
Q

Testing…

A
  • seating
  • clear, concise instructions
  • mode of response
  • transducer selection
43
Q

Threshold Search

A
  • tone presentation
  • Ascending technique
  • descending technique
  • combo approach
  • threshold criteria
  • frequency progression
44
Q

Tone presentation of a threshold search

A
  • give one presentation at dBSL to alert
  • 1-2 second duration
  • pure tone, warble or pulsed tones
  • vary the wait time
45
Q

Ascending technique

A

-start at 0 dBHL and work up in 10 dB steps

46
Q

Descending technique

A

-start at alerting tone and work down in 10 dB steps

47
Q

Combination approach

A
  • give alerting tone and work down in 10 dB steps
  • missed response, go up in 5 dB steps
  • very common now
48
Q

Threshold criteria (ASHA 2005)

A
  • respond 50% of the time

- 2/3 presentations elicit response

49
Q

Frequency Progression

A
  • start at 1k, then 2-8k
  • however 3 and 6 are rarely tested
  • return to 1k for a reliability check then 250 and 500 Hz
  • More than a 20 dB difference between frequencies, add interoctave testing (750, 1500Hz)
50
Q

When there is no response to 1K Hz tone…

A
  • increase by 20 dBHL and try again
  • switch to 500 Hz at same dBHL and try again
  • reinstruct
51
Q

False positives

A
  • eager to please, ringing, nervous, afraid to fail
  • reinstruct, change wait time, change Hz
  • use another signal (Pulse, NBN or warble)
52
Q

False negatives

A
  • need to be sure, afraid, confused, malingering, ADD/ADHD

- reinstruct, change signal , give reassurance of correct answers

53
Q

Pediatric testing

A
  • use second tester to assit
  • try to get low frequency and high frequency info for each ear (500Hz 4000Hz)
  • Need to move quickly
  • keep child’s attention
  • Use reinforcers
54
Q

PTA

A
  • pure tone average
  • 500 Hz + 1k +2k / 3 =PTA
  • may not reflect loss
  • may underestimate impact of loss
55
Q

Tactile Responses

A
  • low frequencies are affected (felt)
  • Transducer contact
  • Profound hearing loss
56
Q

Bone conduction testing threshold search

A
  • combination technique
  • frequency progression
  • unmasked thresholds could be a “better ear” response
57
Q

Bone conduction testing placement options

A
  • mastoid

- forehead

58
Q

Masking

A
  • 2 channel audiometer required
  • used when there is an asymmetrical loss
  • stimulus: speech or noise
59
Q

Speech Stimulus

A
  • babble
  • nonsense
  • speech weighted noise
60
Q

Noise Stimulus

A
  • narrow band noise
  • white noise
  • pink noise
  • fresh noise
61
Q

Effective Masking

A
  • interaural difference of 40 dB (earphones)
  • interaural difference of 50 dB (inserts)
  • just enough to occupy better ear
  • threshold of better ear (non test ear) +10 dBHL
62
Q

Under masking

A

-insufficient masking, the better ear is still contributing

63
Q

Over masking

A
  • excessive masking noise crosses over into test ear

- over estimates the hearing loss in the test ear

64
Q

Plateau Method

A
  • add masking, no shift in TE means threshold is accurate

- if threshold shift by 5 dB or more, increase masking by 10 dB and re establish, continue until stable

65
Q

Occlusion effect in masking

A
  • decrease (improvement) in BC thresholds at 1K or lower frequencies because of tightly fitting earphones
  • seen only in normal listeners and sensorineural losses
66
Q

Masking dilemma

A
  • bilateral conductive hearing loss

- any attempt to mask the non test ear, bleeds into the test ear BC thresholds

67
Q

What are the three main tests of balance testing?

A
  • ENG/VNG
  • Rotational chair testing
  • Postural control