Three Distinct Parts of the Ear
external ear
middle ear
inner ear
Separates External Ear from Middle Ear
tympanic membrane
Parts of Ear that can be Assessed by Direct Inspection and Otoscope
external ear and tympanic membrane
Parts of the Ear Assessed by Testing Hearing Acuity and Conduction of Sound
middle and inner ear
External Ear - Parts of
Auricle or pinna;
External auditory canal;
Modified sweat glands (cerumen);
tympanic membrane
Middle Ear
AKA tympanic cavity;
small, air-filled chamber in temporal bone;
separated from external ear by eardrum and from inner ear by bony partition containing two openings (round and oval windows)
Middle Ear - Parts of
� Tympanic cavity
� Windows
- round
- oval
� Auditory ossicles: (transmit sound waves from
eardrum to inner ear thru oval window)
- malleus
- incus
- stapes
Eustachian Tube
connects middle ear to nasopharynx
Inner Ear (AKA labyrinth)
Fluid filled & made up of:
� bony labryinth
� inner membranous labyrinth
� inner cochlear duct
Inner Ear:parts of bony labyrinth
1. vestibule
2. semicircular canals
3. cochlea
Inner Cochlear Duct - Contains What?
spiral organ of Corti, the sensory organ for hearing
Sensory Receptors
located in vestibule and membranous semicircular canals (inner ear) sense position and head movements;
help maintain static and dynamic equilibrium
Vestibular Nerve
connects with cochlear nerve to form Cranial Nerve VIII (acoustic or vestibulocochlear nerve)
Conductive Hearing
transmission of sound waves thru external and middle ear
Sensorineural Hearing
transmission of sound waves in inner ear;
AKA "perceptive hearing
Cerumen
wax-like substance that keeps tympanic membrane soft;
secreted from modified sweat glands in the external ear canal;
has bacteriostatic properties, and its sticky consistency serves as defense against foreign bodies
Tympanic Membrane
AKA eardrum;
translucent, pearly gray appearance;
serves as partition stretched across inner end of auditory canal, separating if from middle ear;
membrane is concave and located at end of auditory canal in tilted position (top of membrane is closer to au
Distinct Landmarks of Tympanic Membrane
- handle and short process of malleus (nearest auditory ossicle)
- umbo (base of malleus; also serves as center point landmark)
- cone of light (reflection of otoscope light seen as a cone)
- pars flaccida (top of membrane; appears less taut than bottom)
Otoscope
flashlight-type viewer used to visualize eardrum and external ear canal;
speculum = part that enters ear canal;
body = contains light source
Hearing Loss - Risk Factors
- age (>65 years)
- loud noises (decibel levels >85)
- heredity
- otitis media (esp. chronic/untreated)
- some medications (gentamicin, chemo drugs, tinnitus or loss w/ high dose aspirin/NSAIDs, antimalarials, and loop diuretics)
- child of mother who con
Otitis Media - Risk Factors
- age (highest rate 6-18 mos. old, but occurs 4 mos. to 4 years; rarely in adults)
- group child care
- poor air quality (tobacco smoke/air pollution)
- family history
- race/ethnic group (American Indian or Eskimo)
Rinne Test
compares air and bone conduction sounds;
strike a tuning fork and place base of fork on client's mastoid process; ask client to tell you when sound is no longer heard; move prongs of tuning fork to front of external auditory canal; ask client to tell you
Romberg Test
tests client's equilibrium;
ask client to stand w/ feet together and arms at sides and eyes open and then w/ eyes closed: normal finding if client maintains position for 20 seconds without swaying or w/ minimal swaying
Presbycusis
gradual sensoneural hearing loss due to degeneration of cochlea or vestibulocochlear nerve;
common in older clients (> age 50);
clients have difficulty hearing consonants and whispered words (difficulty increases over time)
Weber's Test
helps evaluate conduction of wave sounds thru bone to help distinguish between conductive hearing (sound waves transmitted by external and middle ear) and sensorineural hearing (sound waves transmitted by inner ear);
strike tuning fork softly w/ back of y
Type of Earwax in most Europeans and Africans
wet
Type of Earwax in most Asians and Native Americans
dry (w/ transition in southern Asia)
Inner Ear
- inner ear innervation: acoustic or vestibulochochlear nerve (Cranial VIII)
- hearing pathways: sound vibrates thru air; collected and funneled thru external ear
Auditory system has three levels
Hearing:
Auditory system has 3 levels:
1. peripheral
2. brainstem
3. cerebral cortex
Pathways of hearing:
A. air conduction
B. bone conduction
Hearing Loss
CONDUCTIVE:
mechanical dysfunction (e.g. cerumen, toy, bug, perforated TM or otosclerosis - decreased mobility of ear bones (ossicles)
SENSORINEURAL (perceptive):
nerve (Cranial Nerve VIII), cerebral cortex (e.g. presbycusis/gradual nerve degeneration)
Aging Changes
- cilia coarser; cerumen drier
- otosclerosis (adults): hardening of stapes bone = loss of sound transmission
- infants/young children have short/horizontal external canal, which increases chance of otitis media
Weber Test - Types of Hearing Loss
Conductive Hearing Loss:
client hears w/ POORER ear via bone conduction.
Bone conduction sound is heard longer than or equally as long as air conduction. (BC>=AC)
Sensorineural Hearing Loss:
Client reports lateralization of sound to the good ear due to ne
Weber Test - Findings of Sensorineural Loss
client hears better w/ ear that does not have nerve dysfunction
Hearing Acuity - Testing
- conversational speech
- voice test
- tuning fork tests (Weber, Rinne)
Hearing Acuity - Vestibular Apparatus
- Romberg test (loss of vestibular function)
- client stands w/ eyes closed
- swaying is positive
- may also be indicative of neurological dysfunction
Objective Data - Physical Exam of Tympanic Membrane
color and characteristics
position
integrity of membrane
Position of Ear for Examination - Adult
pinna up and back
Position of Ear for Examination - Child
pinna down and back
Objective Data - Physical Exam of External Ear
inspect and palpate:
size and shape
skin condition
tenderness
external auditory meatus
Objective Data - Physical Exam w/ Otoscope
position head and ear
method of holding and inserting otoscope
external canal: color, swelling
Objective Data - Physical Exam
preparation: position, cleaning ear canal
equipment needed: otoscope w/ bright light, pneumatic bulb attachment, tuning forks in 512 and 1024 Hz
Subjective Data - Health History Questions
earaches
infections
discharge
hearing loss
environmental noise
tinnitus
vertigo
self-care behaviors
Air pressure equalized on both sides of tympanic membrane via
eustachian tube
Video A&P or the Ear
http://www.youtube.com/watch?v=QwTXmaaiGMw
external auditory meatus (external acoustic meatus) is AKA
ear canal
Location of auricle or pinna
External Ear
Location of external auditory canal
External Ear
Location of modified sweat glands (cerumen)
External Ear
Location of tympanic membrane
External Ear
Middle Ear AKA
tympanic cavity
Small, air-filled chamber in temporal bone
Middle Ear
Round and oval windows are found in
Middle Ear
Function of auditory ossicles
transmit sound waves from
eardrum to inner ear thru oval window
What makes up the auditory ossicles
- malleus
- incus
- stapes
Bony labryinth & inner membranous labyrinth are found in the
Inner Ear
Inner Ear is also known as
labyrinth
Inner cochlear duct is found in
Inner ear
Vestibule is part of
bony labyrinth of inner ear
Semicircular canals is part of
bony labyrinth of inner ear
Cochlea is part of
bony labyrinth of inner earspiral organ of Corti
Function of spiral organ of Corti
sensory organ for hearing
Sensory Receptors are located in
vestibule of inner ear
Umbo is located at the
Tympanic membrane near base of malleus
Pars flaccida is located at the
Top of tympanic membrane (less taut than bottom)
Pars tensais located at the
bottom of membrane (appears taut)
Speculum
Part of otoscope that enters the ear
High dose aspirin/NSAIDs and antimalarials can cause
hearing loss
child of mother who contracted rubella while pregnant
can have hearing loss
American Indian or Eskimo have greater increase for
Otitis Media
Group child care can be a risk factor for
Otitis Media
Loss of vestibular function is assessed via
Romberg Test
Otosclerosis in adults
hardening of stapes bone
Degeneration of cochlea or vestibulocochlear nerve can result
Presbycusis (gradual sensoneural hearing loss >50)
Clients have difficulty hearing consonants and whispered words is commonly associated with
Presbycusis (gradual sensoneural hearing loss >50)
Sudden decrease in ability to hear in one ear may be due to
otis media
Client reporting sudden hearing loss should be
referred to a physician
Inability to hear high-frequency sounds may be due to
presbycusis
Draining from ear (otorrhea) may indicate
infection
{Purulent, bloody drainage suggest
infection of external ear (external otitis)
Purulent drainage w/pain & popping sensation is characterized by
otitis media with perforation of the tympanic membrane.
Earache (otalgia) can occur with
ear infection, cerumen blockage, sinus infections, or teeth & gum problems.
Tinnitus can be caused by e
excessive wax, HTN
Vertigo can be caused by
inner ear problem
subjective vertigo
when feeling that room is spinning around you
objective vertigo
when feeling that you are spinning around room
Repeated infections can affect
tympanic membrane
Swimmer's ear
infection of the ear canal
Yearly hearing tests recommended for
those exposed to laud noises for long periods
Cotton-tipped applicators( Q-Tips)
can cause ear wax to become impacted and cause ear damage.
Ears smaller than 4 cm or larger than 10 cm is
abnormal
Abnormal: Maligned or low-set ears may be seen with genitourinary disorders or
chromosomal defects
Tophi (non-tender, hard cream-colored nodule on helix or antihelix
gout (due to uric acid crystals)
Ulcerated, crusted nodules that bleed (mostly on helix) are a sign of
skin cancer
Redness, swelling, scaling, or itching is a sign of
otitis externa
Painful auricle or tragus is associated with
otitis externa or postauricular cyst
Tenderness over the mostoid process suggests
mastoiditis
Tenderness behind the ear may occur with
otitis media
Foul smelling, stick, yellow discharge is associated with
otitis externa or impacted foreign body
bood or watery drainage can be a sign of
skull trauma
Red, bulging eardrum and distorted with deminished or absent light reflex
acute otits media
Yellow, bulging tympanic membrane with bubbles behind is most likely
serous otitis media
White spots on tympanic membrane
scarring from infections
Client feet are together with eyes closed and he moves feet apart to prevent fall or starts to fall from loss of balance. This indicates a
vestibular disorder
Problem with vestibular apparatus may indicate
neurological problem
Tympanic membrane of left ear reveals
cone of light at 7 o'clock position
Tympanic membrane of right ear reveals
cone of light at 5 o'clock position
Damage to the spiral organ of Corti leads to
sensorineural hearing loss
sensorineural hearing loss occurs in when damage is located in the
inner ear
Measeles is a considered
a risk factor for hearing loss
Older clients' eardrums may appear
cloudy as a normal part of aging with prominent landmarks due to atrophy of the tympanic membrane
Prominent landmarks when examining the clients tympanic membrane can be a sign of
obstructed Eustachian tubes
What test should be performed when a client has difficulty a hearing conversation due to background noise or background conversations
Weber
What test should be performed if a client has vertigo
Romberg test
Inability to hear whisper sounds indicates
presbycusis (hearing loss)
Clinically insignificant projection on the auricle
Darwin's tubercle
High tone frequency loss of an elderly client is considered
a normal part of aging
Ototoxic med such as antibiotics can result in
tinnitus