Audiology (131) Unit 2 Exam

Otoscopy definition

examination of ear canal and tympanic membrane

Ostocopy clinical relevance

Diagnostic tool for various ear conditions

Ostocope standard components (4)

Handle, light source, speculum, magnifying lens

Otoscope step-by-step procedure (4)

1. external inspection

2. straighten ear canal

3. insert speculum

4. systematic examination

How to straighten the ear canal for adults? children?

adults: pull up and back

children: pull down and back

Otoscopy - Normal Findings of the external canal

Skin-lined, small amounts of cerumen

Otoscopy - Normal Findings of the tympanic membrane

pearly gray, slightly concave, with visible handle of malleus and cone of light

Otis Externa Characteristics - Otoscopy Abnormal findings

redness, swelling, discharge, pain

cause: bacterial or fungal infection

Otis Media Characteristics - Otoscopy Abnormal findings

red/bulging TM, effusion

known complications: tympanosclerosis and cholesteatoma

Earwax impaction Characteristics - Otoscopy Abnormal findings

hearing loss, earache, tinnitus

removed via irrigation or manual extraction

Foreign bodies Characteristics - Otoscopy Abnormal findings

common objects (insects, beads, cotton swabs

require safe removal

Acoustic immittance includes… (3)

impedance, admittance, compliance

Impedance (z)

opposition to energy flow

determined by resistance, mass, and stiffness

Admittance (y)

ease of energy flow

the reciprocal of impedance

Compliance

how well the TM moves in response to pressure changes

• low = stiff

• high = hypermobile

Acoustic immittance testing equipment (4)

loudspeaker, microphone, air pump, probe assembly

• good for difficult-to test pop

  • non-invasive, no behavioral response required

• probe tone adults = 226Hz

  • infants = 1000Hz

Tympanometry - Type A

(shape/peak & What it suggests)

Normal peak near 0 daPa

normal middle ear function

Tympanometry - Type As

(shape/peak & What it suggests)

shallow peak

stiffness (eg. otosclerosis)

Tympanometry - Type Ad

(shape/peak & What it suggests)

very high/tall peak

flaccid TM or ossicular discontinuity

Tympanometry - Type B

(shape/peak & What it suggests)

Flat, no peak

TM perforation or fluid in middle ear

Tympanometry - Type C

(shape/peak & What it suggests)

Peak shifted to negative pressure

Eustachian tube dysfunction

ipsilateral vs contralateral reflexes

ipsilateral = same ear

contralateral = opp ear, crossing at the superior olivary complex

ART (Acoustic Reflex Threshold) definition

lowest intensity that triggers a measurable contraction

acoustic reflex definition

contraction of the stapedius muscle in response to loud sound

ART outcomes and their meaning

• present at normal level

• absent

• present at low intensity

• present at elevated level

present at normal level = typical funciton

absent = conductive HL or severe SN HL

present at low intensity = mild cochlear HL

present at elevated level = retrocochlear pathology

Acoustic reflex decay is a measure of …

how long the stapedius can sustain contraction

• tone presented 10dB above ART

Absent acoustic reflex means…

conductive loss

abnormal decay (acoustic reflex) means…

retrocochlear issue (eg. auditory nerve tumor)

Webber test (con and SN)

fork on midline of forehead

test laterlization

• conductive loss = laterizes to the ear

• SN = away from the ear

Rinne test

AC vs BC

• conductive hl = negative, BC > AC

• Normal or SN = positive, AC > BC

Air conduction

Tests full auditory pathway (outer, mid, inner)

shows DEGREE of HL but not type

bon conduction

stimulates cochlea

determines TYPE of HL

Audiogram symbols

Degrees of hearing loss

• normal

• slight

• mild

• moderate

• mod-severe

• severe

• profound

• normal = -10 to 15

• slight = 15 - 25

• mild = 25 - 40

• moderate = 40 to 55

• mod-severe = 55 to 70

• severe = 70 to 90

• profound = 90+

Patient responses, false positive

RESPONDS when NO sound was presented

Patient responses, false negative

FAILS to respond to a sound they DID hear

Can air conduction alnoe tell you the type of hearing loss?

no, BC needed

What range of HL does 60dB fall under?

moderatley-severe (55-70dB)

cross-hearing

stimuli reaches non-tested ear

• solved by masking

Interaural Attenuation (IA)

reduction in signal strength as sound travels from one ear to the other

Shadow audiogram

audiogram that actually represents the non-tested ear’s hearing

• due to cross hearing and IA

Types of masking noise

narrowband noise = used for pure-tone audiometry

speech noise = used for speech audiometry

Plateau method

gold standard for clinical masking

• increase masking in non-test ear until plateau is reached

masking problems (3)

udermasking

overmasking - crosses back to the test ear

occlusion effect - covering the ear boosts low frequ BC thresholds

• must account for this during BC masking

Bone conductioni IA is essentially __ dB

0

• meaning masking is almsot ALWAYS needed for BC testing

occlusion effect impacts ____ frequencies specifically

low

SRT (speech recognition threshold)

lowest level speech is UNDERSTOOD 50% of the time

• uses spondiac (two-syllable equal stress)

SDT (speech detection threshold)

lowest level at which speech is DETECTABLE - not necessarily understood

PTA is calculated from witch 3 frequencies?

500, 1000, 2000 Hz

Match behavioral tests to age range

• BOA

• VRA

• play audiometry

• Standard

(Boy vat pus stankkk)

• BOA= birth - 6mo

• VRA = 6mo - 2.5/3yrs

• Play audiometry = 2-5yrs

• Standard = 5+yrs

The gold standard for newborn hearing screening is _____

AABR - detects neural pathway integrity

Which test screens cochlear function specifically?

OAEs - quick and noninvasive

Auditory Brainstem response (ABR) - Which wave corresponds to which structure?

• I

• III

• V

• I - auditory nerve

• III - SOC (superior olivary complex)

• V - Lateral lemniscus/IC

  • most clinically SIGNIFICANT

True or false: TEOAES CAN confirm cochlear function but CANNOT rule out neural problems

True