Pure Tone Audiometry Flashcards Preview

Intro to Audiology > Pure Tone Audiometry > Flashcards

Flashcards in Pure Tone Audiometry Deck (12):
1

Pure Tone Audiometry

Done with audiometer

Find hearing threshold

Frequences range from 125Hz to 20,000Hz
Typically test 250 Hz to 8 kHz; No speech information after 8K Hz

“High Frequency Audiometry” goes from 8 to 20 kHz; reserved for those at risk: military, cancer patient or anyone receiving ototoxic drugs

-10dBHL to 120dBHL Loudness Level
Typically stop around 110

Bone conduction:
250 Hz to 4 kHz – equipment can only be calibrated to 4kHz

Stop between 50 dBHL and 80 dBHL; After this vibration felt and not heard; vibrates on head

2

Threshold

when patient hears the tone 50% of the time

3

Interaural attenuation

crossover

Inserts = 60 dBHL difference level will crossover

Headphones = 40 dBHL difference level will crossover

4

Air Conduction Audiometry

Proper placement is super important

Inserts = preferred over headphones
Procedure

Begin at 1kHz and then go up to 8kHz then back down

Begin at 30 dBHL
Increase to 50 dBHL if no response
Increase in 10 dBHL increments if no response at 50 dBHL

Once they respond, follow the “down 10, up 5” method

Plot on audiogram

Use pulsed warble (pure) tones
Play 2-3 beeps, longer if needed
PTA – average of 500, 1000, & 2000 Hz

If the difference btwn octaves is 20 dB or more, test the inner octaves as well

5

Bone Conduction Audiometry

Purpose: see their sensorineural sensitivity

CHL/MHL vs SNHL

Placed on the mastoid, under hair: Loudest behind the ear because you have added benefit of middle ear bone movement from vibration as well

Glasses & pinna will vibrate if touched with sensor; cause false positive

Same method as air conduction (start at 1kHz; up then down)

Tactile response (felt)

Cross Hearing
(interaural attenuation is 0 bc everything vibrates)

If the difference btwn octaves is 20 dB or more, test the inner octaves as well

6

Sensorineural HL on Audiogram

AC & BC outside of normal

Air-Bone Gap

7

Mixed HL on Audiogram

AC & BC outside of normal

Air-Bone Gap
>10 dBHL between AC and BC

8

Conductive HL on Audiogram

AC outside of normal, BC within normal

Air-Bone Gap
>10 dBHL between AC and BC

9

Other types of Audiometry

Automatic Audiometry: Smartphone applications; generally not reliable

Computerized Audiometry: Mostly for research

10

Masking

AKA: Interaural attention, Cross hearing

What does it do:
Distracts one ear so you know the response is true: a "masked response"

11

BC Masking

Bone conduction is tested to determine if there is SN HL; check the difference btwn AC tests; if more than 10dB difference, must mask for BC testing

BC masking requires both ears to be masked and tested, one at a time, to get the threshold for each ear

12

AC Masking

Required when there is sufficient difference btwn SL in the ears

Headphones: 40 dBHL
Inserts: 60 dBHL