Found. of Aud. Exam 2 — Deck 2: Audiogram, Speech Audiometry & Etiologies

Symbol: unmasked air conduction, right ear.

• O (red)

Symbol: unmasked air conduction, left ear.

• X (blue)

Symbol: masked air conduction, right ear.

• Δ (triangle)

Symbol: masked air conduction, left ear.

• □ (square)

Symbol: unmasked mastoid bone conduction, right ear.

• <

Symbol: unmasked mastoid bone conduction, left ear.

• >

Symbol: masked mastoid bone conduction, right ear.

• [

Symbol: masked mastoid bone conduction, left ear.

• ]

Symbol: unmasked forehead bone conduction.

• V (unspecified ear)

Symbol: sound field response.

• S

What do 'A' and 'CI' mean on an audiogram?

• A = aided response (with a hearing aid)

• CI = cochlear implant response

Why are sound field results not ear specific?

• The sound comes from a speaker, so either ear could be responding

How is a 'no response' marked on an audiogram, and what does it mean?

• The symbol has a downward arrow

• The person didn't hear the audiometer's loudest level, so it isn't a threshold

Why can't you name the type of loss from an air-conduction-only audiogram?

• Type requires bone conduction results

Audiogram pattern: air conduction abnormal, bone conduction normal, air-bone gap present. What type?

• Conductive hearing loss

Audiogram pattern: air and bone conduction equally abnormal, no air-bone gap. What type?

• Sensorineural hearing loss

Audiogram pattern: bone conduction abnormal, air conduction even worse, air-bone gap present. What type?

• Mixed hearing loss

How large must the gap between air and bone conduction be to count as an air-bone gap?

• More than 10 dB

What is the most common type of hearing loss?

• High-frequency sensorineural hearing loss

Configuration: normal in the lows and highs, worse in the middle frequencies.

• Cookie bite

Configuration: a dip worst around 4000 Hz with recovery at 8000 Hz.

• Noise notch

Configuration: worse in the low frequencies, improving toward the highs.

• Reverse slope (rising, upward sloping)

Configuration: normal lows dropping sharply to a severe loss in the highs.

• Ski slope

What does 'bilateral asymmetrical' hearing loss mean?

• Hearing loss in both ears, but with a different degree in each

What does 'unilateral' hearing loss mean?

• Hearing loss in only one ear

In what order should you describe an audiogram result?

1. Degree

2. Configuration (shape)

3. Type

4. Which ear (bilateral, left or right)

When an audiogram has masked and unmasked results at the same frequency, which do you read?

• The masked result

• It's the true threshold

What three questions about progressive hearing loss does the course raise?

• What is it?

• Why is it important?

• How and why can it be missed?

What does 'phonemically balanced' mean for a word list?

• It contains all English phonemes in initial, medial and final positions

Where did the first speech audiometry word lists come from, and why were they made?

• From Veterans Affairs work after WWII, because there was no measure of hearing for real-world speech

What does the 50% rule mean in speech audiometry?

• The threshold is the level where speech is understood (or detected) at least 50% of the time

Define the speech recognition (reception) threshold.

• The softest level where a person can understand speech at least 50% of the time

What is a spondee?

• A two-syllable word with equal stress on both syllables

Give three examples of spondees.

Any three:

• Hot dog

• Baseball

• Cupcake

• Playground

• Toothbrush

• Birthday

• Duck pond

• Horseshoe

During the SRT search, what do you do after a correct response, and after an incorrect one?

• Correct: drop 10 dB

• Incorrect: go up 5 dB

How close must the SRT be to the pure-tone average for results to be reliable?

• Within ±5 dB

A patient's pure-tone average is 10 dB HL. What SRT range would confirm reliability?

• 5–15 dB HL

Why do many audiologists start testing with the SRT?

• Speech is a more natural stimulus

What does 'fair' reliability on an audiogram mean?

• Results are somewhat reliable

• It's common for kids, and their SRT may better reflect their loss than pure tones do

What does 'poor' reliability on an audiogram mean?

• A retest is needed

How is the SRT tested with a young child or someone with an intellectual disability?

• Picture pointing on a spondee board ('Show me birthday')

Define the speech detection (awareness) threshold.

• The softest level where a person can detect, or is aware of, speech at least 50% of the time

When would you use SDT/SAT instead of SRT?

• When a child won't or can't point or repeat

How does the SDT compare to the SRT for the same person?

• It's always lower (softer): you can hear that someone spoke before you can tell what was said

Must the SDT agree with the pure-tone average within ±5 dB?

• No

Name three stimuli used for SDT/SAT testing.

• Body parts ('Where's your nose?')

• The person's name

• Spondees

Define the most comfortable listening level.

• The volume at which listening is most comfortable

Name four uses of the most comfortable listening level.

• Inter-test reliability

• A reference level for word recognition testing

• An indicator of narrow dynamic range

• Hearing aid fitting

Define the loudness discomfort level (uncomfortable listening level).

• The point where a patient can no longer tolerate a tone or speech for more than 1–2 seconds

• Uncomfortable, not painful

What loudness discomfort level is normal?

• 90 dB or above

Define hyperacusis.

• Intolerance to all loud sounds

• A reduced loudness discomfort level (below 90 dB)

Define dynamic range.

• The span between a person's threshold and their loudness discomfort level

Why does a narrow dynamic range make hearing aid fitting harder?

• There's little room to make sound audible without pushing it into the uncomfortable range

• Thresholds worsen with hearing loss, but loudness tolerance doesn't move up

What does word recognition testing measure?

• How well a person can understand (discriminate) speech sounds

• It's reported as a percentage and is not a threshold

At what level is word recognition testing presented?

• At one fixed level, 30–40 dB above the person's SRT

How many words are used in word recognition testing?

• A 50-word list

• You can stop at 25 if 4 or fewer are missed, otherwise give all 50

Which sounds are most commonly missed on word recognition testing?

• High-frequency consonants in the final position, such as /s/, /f/ and /th/

What is a carrier phrase?

• A phrase that introduces each test word, such as 'Say the word ___.'

Why are recorded word lists considered best practice?

• They're consistent: no accent, recorded in a sound-treated room

• (Kids often do better with live voice.)

What does the VU meter on an audiometer do?

• Keeps live-voice speech at a consistent level

Why might a ski-slope loss have an SRT and pure-tone average that don't agree?

• The pure-tone average includes the poor high frequency, while the SRT reflects the better lows

• The Fletcher average fits better

Word recognition score 92–100%: interpretation?

• Excellent

Word recognition score 84–90%: interpretation?

• Very good

Word recognition score 78–82%: interpretation?

• Good

Word recognition score 70–76%: interpretation?

• Fair

Word recognition score 60–68%: interpretation?

• Poor

Word recognition score below 60%: interpretation and likely recommendation?

• Very poor

• A cochlear implant may be recommended for better word recognition

What can hearing aids do for speech, and what can't they do?

• They make sound louder

• They enhance speech and reduce background noise

• They can't make speech clearer or fix the ear

Why is speech-in-noise testing done?

• Simulates real-life struggles of people with hearing loss or auditory processing problems

• Qualifies their hearing challenges

• Helps with counseling about the impact of hearing loss

Name two commercial speech-in-noise tests.

• SPIN and WIN

When is masking needed for SRT testing?

• When the difference between the better ear's SRT and the poorer ear's pure-tone average is greater than 40 dB (air conduction)

What does a conductive loss on the audiogram tell you about where the problem is?

• Something is wrong with the outer or middle ear

Define microtia.

• A small or malformed outer ear

Define atresia.

• Absence or closure of the external ear canal

Why are collapsing ear canals common in elderly patients?

• Their ear cartilage is more flaccid

Name two foreign bodies commonly found in ear canals.

• Bugs

• Beads

• Pencil lead

Describe otitis externa.

• An outer ear canal infection with swelling, pus and weeping

• Treated by a physician

How does a tympanometer work?

1. A probe seals the ear canal

2. It pumps air pressure in and pulls it back out

3. This measures how well the eardrum and ossicles move

What does ear canal volume on a tympanogram tell you about?

• The outer ear only

Tympanogram type: normal peak, normal pressure.

• Type A (normal middle ear)

Tympanogram type: shallow peak, stiff middle ear.

• Type As

Name two etiologies associated with a Type As tympanogram.

• Otosclerosis and a scarred eardrum

Tympanogram type: flat, no peak.

• Type B

Name two etiologies associated with a Type B tympanogram.

• Otitis media with effusion and cholesteatoma

Tympanogram type: very deep peak, too much movement.

• Type Ad

Name an etiology associated with a Type Ad tympanogram.

• Ossicular discontinuity (disarticulated ossicular chain)

• Also hyperflaccidity in elderly patients

Tympanogram type: peak shifted to strong negative pressure.

• Type C

What causes a Type C tympanogram?

• Negative middle ear pressure that pulls the eardrum inward, as in Eustachian tube dysfunction

What tympanogram is classic for Eustachian tube dysfunction?

• Type C

Name two causes of a perforated eardrum.

• Blasts and head injuries

About what percentage of children have at least one bout of middle ear effusion?

• About 90%

What is otosclerosis (otospongiosis)?

• Bony growth on the footplate of the stapes

Does the amount of otosclerosis predict the degree of hearing loss?

• No

What is the first (most common) etiology of sensorineural hearing loss?

• Age (presbycusis)

Name four sources of noise-induced hearing loss.

• Motorcycles

• Power tools

• Concerts

• Guns

Define ototoxicity.

• Damage to the hair cells from medications that are toxic to the ear

Name three ototoxic medications.

• Chemotherapy drugs such as cisplatin

• '-mycin' antibiotics

• Aspirin in large doses

How can trauma such as a blast, accident or airbag deployment cause a mixed loss?

• It can damage both the cochlea and the conductive structures

What causes Ménière's disease?

• Overproduction of endolymph in the scala media (endolymphatic hydrops)

Name the classic symptoms of Ménière's disease.

• Fluctuating low-frequency hearing loss, strong vertigo and roaring tinnitus

• Unpredictable from day to day