csd3185 cumulative - exams 1-3

three main functions of outer ear

protection

amplification

localization

outer ear function

protection

anatomy of external ear and ear canal curvature

• keeps things out

• protects inside (middle/inner/brain)

what is the barrier between the outer and middle ear?

ear drum/tympanic membrane

healthy ear drum

top circle

manubrium of the malleus

healthy ear drum

left circle

long process of the incus

healthy ear drum

bottom circle

umbo

cone of light

where is it located

light reflex on ear drum seen in a healthy, clear ear

anterior inferior quadrant (bottom right)

outer ear function

amplification

boosts frequencies in the 2-5 kHz range

due to curvature

outer ear function

localization

timing and intensity differences between 2 ears + pinna = help us identify where sound is coming from and we look in that direction first

the outer and middle ear are filled with ___

air

3 bones of middle ear

malleus

incus

stapes

the bones in the middle ear are fused together/free flowing

free flowing

when sound makes the ear drum move in and out, what does it do to the middle ear bones

makes the middle ear bones move together

middle ear function

impedance matching

ossicles pivot against each other to boost sounds ~30 dB to make up for the loss of intensity when moving from air → fluid (middle → inner)

middle ear function

how is impedance matching accomplished

difference in area of TM and stapes

• boosts 24.6 dB

bones pivot → pressure force is directed to small area → goes to cochlea

middle ear function

too much sound = stapes pushes into cochlea and causes _______ which we don’t notice until it happens

hearing loss

middle ear

eustachian tube

runs from middle ear to back of throat

purpose: keep middle ear at a normal atmospheric pressure

pressure of tube moves ear drum in and out = popping of ear drum

inner ear is filled with _____

fluid

inner ear

semicircular canals

fluid-filled canals related to balance, keeping fluid level even when leaning side-to-side

inner ear

cochlea

organ of hearing

within cochlea

internal hair cells

• how many rows

• function

1 row

fine tune frequencies

within cochlea

external hair cells

• how many rows

• function

3 rows

protective

within cochlea

what do hair cells do

hair cells move in a wave caused by stapes hitting basilar membrane; this wave travels along fluid/cells until it hits nerve associated with its pitch

within cochlea

tonotopic organization

different areas of the cochlea have different nerves tuned to different pitches

inner ear function

change:

mechanical vibration of inner ear fluid → neural impulses transmitted to the brain

otoscopy examines what 3 parts of the ear

outer

pinna

ear canal

tympanic membrane

to prevent patient pain and discomfort:

hold otoscope like a ____

brace patient with _____

pencil

pinkie

due to ear canal curvature:

pull pinna ___ and ___

curve otoscope ___

pull pinna back and up

curve otoscope up

otoscopy

examine the good/bad ear FIRST

good ear first

• prevents infection spread

• see normal anatomy

helix

1

tragus

4

lobe

6

concha

8

external auditory canal

9

normal otoscopy

darwin’s tubercle

bump of cartilage; common

no effect on hearing

normal otoscopy

prominent ears

“cup ears”; common; due to genes, malformed in utero

no effect on hearing

normal otoscopy

preauricular tag

small skin tag; common in newborns

need to be referred to MD due to association with medical conditions

no effect on hearing

normal otoscopy

preauricular pit

pit on external ear; embryo develops weird

normal otoscopy

hairy tragus

often in men

interferes with normal migration of wax - leads to wax accumulation

normal otoscopy

hairy ear

occurs in males; genes

no effect on hearing

normal otoscopy

creased lobe

external = no hearing effect BUT

piercings might effect AuD pulling ear to see in

first 1/3 of a normal ear canal is

last 2/3 of a normal ear canal is

first 1/3: cartilaginous

last 2/3: bony

normal otoscopy

healthy ear drum (2) components

• semi-transparent

• light reflecting

normal otoscopy

wax is normal/abnormal

normal

normal otoscopy

dry cerumen

dried, flaky, excessive wax

looks like scabs

common in native american/indian

normal otoscopy

wet cerumen

moist, soft, brown

common in white and african

normal otoscopy

cerumen

• if completely obstructing canal:

• if large amount, but not completely obstructing:

if completely obstructing canal: can cause HL

if large amount, but not completely obstructing: AuD can’t see eardrum; doesn’t necessary imply HL

both

ENT/urgent care will flush or suction

in right ear, handle of malleus points:

in left ear, handle of malleus points:

right = right

left = left

normal otoscopy

tympanosclorosis

what does it look like in otoscopy

patches of calcification on ear drum

commonly associated with ventilation tubes, perforations, repeated infections

typically does not effect hearing

looks like

still see malleus

no cone of light/transparency

normal otoscopy

what type of tube is this

PE tube

• usually fall out on their own, hopefully when no longer needed

• functional life of 6-12 mo.

normal otoscopy

what type of tube is this

T tube

• must be surgically removed

• longer functional life, usually years

normal otoscopy

ventilation tubes

allow continuous aeration of the middle ear; bypasses dysfunctional eustachian tube

disordered otoscopy: pinna

anotia

absence of external ear

if internal structures intact but no opening = will have HL

conductive HL

disordered otoscopy: pinna

microtia

underdeveloped external ear; maybe underdeveloped/missing ear canal also

need to do bone conduction testing

conductive HL

disordered otoscopy: pinna

auricular hematoma

“cauliflower ear”

repeated blunt trauma causes blood to collect and bruise

scarring or thickening of cartilage can occur

disordered otoscopy: pinna

keloids

overgrowth formed by connective tissue

response which occurs due to trauma/piercings

more common in those with more skin pigment

disordered otoscopy: pinna

carcinoma

skin cancer; occurs on pinna exposed to repeated sun exposure

refer to MD

disordered otoscopy: pinna

split lobule

results from pulled earring/heavy earring wear

disordered otoscopy: pinna

contact dermatitis

reaction to nickel found in jewelry

disordered otoscopy: canal

aural atresia

malformed/none/very small ear canal

associated with microtia

conductive HL

disordered otoscopy: canal

hyper cerumenosis

buildup of excessive earwax; didn’t produce or clear correctly

treat by frequent removal

disordered otoscopy: canal

impacted cerumen

dark colored, tightly packed wax

does not cause HL

disordered otoscopy: canal

occluded cerumen

completely blocks the canal

needs to be removed

causes HL

disordered otoscopy: canal

does impacted or occluded cerumen cause hearing loss

occluded cerumen

disordered otoscopy: canal

foreign bodies

must refer to MD to have bodies removed

disordered otoscopy: canal

abrasion of canal

caused by sticking things in ears to scratch them

not problem UNLESS it causes/you get an ear infection

disordered otoscopy: canal

exostoses

growth: excess bony growths

due to cold water/pressure (sky divers/deep sea)

disordered otoscopy: canal

osteoma

growth: bony tumors grown into ear

disordered otoscopy: canal

polyps

growth: projecting masses of swollen or tumorous membrane

if starts to affect hearing = needs to be treated

disordered otoscopy: canal

papilloma

growth: benign tumor resulting from overgrowth of epithelial tissue

disordered otoscopy: canal

fibroma

growth: benign tumor consisting of fibrous tissue

disordered otoscopy: canal

collapsing ear canal

caused by deficiency in supporting cartilage; elderly

caused by headphones that push on your ear

disordered otoscopy: canal

stenosis of external auditory meatus

abnormal narrowing; caused by repeated infections or trauma

disordered otoscopy: canal

otitis externa/external otitis

“swimmers ear”; caused by fungal or bacterial infection

constantly getting ears wet leads to damage to ear immune defenses; leads to infection

inflammation/pus

refer to MD

conductive HL

disordered otoscopy: canal

necrotizing malignant external otitis complications

necrotizing: causing the localized death of living tissue

malignant: tending to infiltrate and spread from one part of body to another

external otitis can eat through ear and into brain; fatal

disordered otoscopy: eardrum/TM

TM perforation

hole in ear drum

susceptible to infection

spontaneously heals or can be patched

conductive HL - determined by position on TM

disordered otoscopy: eardrum/TM

myringotomy

incision made as part of insertion of PE tube

eventually skin will close around

disordered otoscopy: eardrum/TM

traumatic perforation

result of blow to head or trauma from something inserted into TM

disordered otoscopy: eardrum/TM

perforation

could be from blow to head, vibrations from explosion; repeated ear infections

disordered otoscopy: eardrum/TM

monomere

healed perforation with incomplete fibrous layer

looks like hole but is not

might be HL

disordered otoscopy: eardrum/TM

myringitis

infection of the eardrum; rapid onset

usually self resolves

conductive HL

disordered otoscopy: middle ear

glomus tumor

middle ear growth: blood-fed tumor originating from cells found in middle ear

reddish-blue mass behind intact TM; pulsing

refer to ENT for diagnosis

conductive HL for most

disordered otoscopy: middle ear

cholesteatoma

middle ear growth: invasive, benign progressively enlarging tumor 

starts at TM where layer is pinched and forms a pocket in middle ear where things get stuck and lead to cholesteatoma

needs to get surgically removed

conductive HL

disordered otoscopy: middle ear

otosclerosis

middle ear growth: abnormal bone grows over 3 middle ear bones

looks like: reddish blue tinge from behind TM

often in pregnancy

treated surgically - could grow back or use H.A.

conductive HL

disordered otoscopy: middle ear

otitis media

middle ear infection; inflammation with accumulation of infected fluid in middle ear; bulging TM; pain; drainage of pus into ear canal

conductive HL

disordered otoscopy: middle ear

disarticulation of the ossicles

breakage of the ossicles or their attachments; due to physical trauma

audiometry

within what range of frequencies are octaves tested with an audiometer

250 - 8000 Hz

audiometry

should the patient be able to see you

should you see them

no

yes

audiometry

what is the name of the ASHA Cstandardized procedure for a hearing test

Modified Hughson-Westlake Procedure

audiometry: modified hughson-westlake procedure

you change dB by how much when testing hearing thresholds

• if patient responds:

• if patient does not respond: 

• if patient responds: down 10

• if patient does not respond: up 5

audiometry: modified hughson-westlake procedure

when testing thresholds: vary dB level until you find lowest where patient responds correctly ___% or _____ times

50% or 2/3 times

audiometry: modified hughson-westlake procedure

start at what frequency and dB level?

1000 Hz, 30 dB

audiometry: modified hughson-westlake procedure

what ear do you start in

the better ear

if no better ear = right ear

audiometry: modified hughson-westlake procedure

once you reach 8000 Hz, where do you go next?

1000 Hz

then 500 Hz, then 250 Hz

audiometry: modified hughson-westlake procedure

if there is ___ dB between adjacent frequencies, test inter-octaves (750, 1500, 3000, 6000 Hz)

20 or greater

audiometry: modified hughson-westlake procedure

do you test one ear at a time?

yes

audiometry

0 dB HL

not the absence of sound; equal to lowest amount of sound pressure

threshold for young, healthy adults

audiometry

minimal hearing curve

done on best hearing young adults to find normal thresholds and convert dB HL to dB SPL

extreme frequencies take more sound pressure than the best threshold of hearing (our hearing range)

audiogram

symbol for: right ear, air conduction

red circle

audiogram

symbol for: left ear, air conduction

blue X