CODI 382 Audiology Exam 1

raymond carhart

who is the grandfather of audiology?

CC Bunch

who wrote the first audiology textbook?

hospital setting, private practice, school system

what are three settings that audiologists are typically employed?

the eardrum

what is the tympanic membrane also called?

origins in the military during and after world war II

how did modern audiology come to be?

certification is voluntary things you can get, license is required to practice

what is the difference between licensure and certification?

American Speech-Language-Hearing Association (ASHA)

________ certification (Certificate of Clinical Competence) is required of all of it's members. Requires 10 continuing education hours per year

American Board of Audiology (ABA)

_______ is voluntary. Requires 20 continuing education hours per year. ____ has established specialty certification in pediatrics and cochlear implants

LBESPA (Louisiana Board of Examiners for Speech Pathology and Audiology )

who gives licenses for audiologists in louisiana

in the school setting

where is there a shortage of audiologists

hospitals (12%) and physician offices (23%)

where do the majority of audiologists work

private practice owner (19%) and employee (9%)

what is the fastest growing employment setting for audiologists

frequency and intensity

physical sound is ____ and ____

a series of disturbances of molecules within, and propagated through, an elastic medium such as air

what is sound in the physical sense

a sound is an auditory experience—the act of hearing something

what is sound in a psychological sense

higher

a solid has ___ elasticity than a liquid or gas

Free Vibration - vibration of a mass without any outside force

Forced Vibration - Vibration of a mass controlled by some outside force

what is the difference between free vibration and force vibration

oscillating

sine waves are ____ waves

hertz

what is frequency measured in?

decreases

as the length of the wave increases, its frequency ____

velocity

the speed at which a wave travels

wavelength

the measurement of one point to the next in a wave

interference

when more than one tone is introduced, there are interactions among sound waves, or ____

pure tones

______ are the simplest sound waves

complex waves

____ are multiple pure waves

decreases

as the frequency increases, the wavelength ___

344m/sec (1,130 feet/sec)

whats the speed of sound through the air

3

how many systems in the body work together to keep us upright?

vestibular, proprioceptive and oculomotor (visual)

what are the 3 systems that work together to keep us upright

false

disorders of the outer ear will always cause a hearing loss

true

disorders of the inner ear typically cause sensory hearing loss

the tympanic membrane is larger than the oval window to increase the force of the vibrations to allow them to pass to the liquid of the cohclea

why is the tympanic membrane large than the oval window

Cartilaginous

Contains sebaceous glands for cerumen production

Contains hair follicles

The combination of hairs and cerumen helps to keep foreign objects, such as insects, from passing into the inner two-thirds of the canal

outer portion of outer ear

Protects the T M from trauma and foreign objects

Keeps T M at constant temperature and humidity levels

Serves as a sound filter

Reduces low frequencies

Resonator for frequencies between 2K and 7K Hertz.

what are some important functions of the external auditory canal

55 mm squared

what is the total vibrating surface area of the tympanic membrane

about .07 mm

what is the thickness f the tympanic membrane

conductive hearing loss

when conditions occur that interfere with or block the normal sound vibrations transmitted through the outer ear

conductive hearing loss

____ also arises from disorders of the middle ear

60 dB

air-bone- gaps never exceed ______

basal cell carcinoma

whats the most common form of skin cancer

to collect and funnel sound through the auditory canal and send to the tympanic membrane

what is the purpose of the outer ear

cartilage

what is the pinna made of

the osseocartilaginous

This portion of the external auditory canal is where cartilage and bone meet

atresia May occur in cartilaginous portion, bony portion, or both

May occur in one or both ears

May occur in isolation or with other anomalies

Associated syndromes/causes of Atresia

Treacher Collins Syndrome

CHARGE syndrome

Burns, trauma, or frostbite

disorders of the outer ear involving lack of canalization

atresia

Conductive hearing loss is directly related to the area and the amount of occlusion

When an atresia is seen, it must be suspected that the tympanic membrane and middle ear may likewise be involved

Atresia cannot be treated with traditional hearing aids

stenosis

disorder of the outer ear that involves narrowing of the EAC

Does not directly cause a hearing loss, but can be easily clogged by earwax/debris

does stenosis cause hearing loss?

collapsing auditory canals- Conductive hearing loss from collapsed auditory canals can appear during examination

what disorder of the outer ear does this describe? Pressure of the supra-aural headphones can depress the auricle against the head, causing a blockage to the opening of the canal thus attenuating sound

It is important to inspect the ear prior to testing

Inserts receivers circumvent the effects of collapsing ear canals

May be seen in 4% of a typical audiology caseload

More common among elderly patients

hearing loss may or may not result

does hearing loss always occur from foreign bodies in the ear

disorders of the outer ear: foreign bodies

If an object is pushed past the osseocartilaginous junction of the E A C, swelling may occur

external otitis

An infection that occurs in the skin of the external auditory canal

Also referred to as swimmer's ear

otomycosis

fungal external ear infection

Depending on swelling or accumulation of infectious debris, mild hearing loss may be present

can external otitis cause hearing loss

osteomas

bony tumors in the outer ear

extoses

the outward projections for the surfaces of bone

Causes:

Excessive pressure buildup during Middle-ear disorder may cause T M to rupture

Direct trauma

cotton swap or hair pin

Sudden pressure in the E A C

hand clapped over ear

explosion

Rapid changes in E A C pressure - barotrauma

scuba diving

what can cause perforations of the tympanic membrane

perforation of the TM

Immittance measures can detect perforations that are not readily visible with the naked eye

Amount of hearing loss depends on size and placement of perforation

Treatment:

Most T M perforations heal spontaneously

Surgical repair known as myringoplasty may be needed

tympanosclerosis

T M may become thickened or scarred in response to infection

Does not respond well to medical or surgical treatment

Calcium plaques may appear

Added mass to the T M interferes with its vibration

Hearing loss may or may not result

cerumen (earwax)

what is the substance that is produced by our ear that is antimicrobial and antifungal

the outer portion of the external auditory canal

what portion of the outer ear contains hair follicles

D. insert ear buds that are too loud

all of these could cause a pressure change and perforate the tympanic membrane besides. a) direct trauma b) change in pressure c) stabbing a bobby pin d) insert ear buds that are too loud

medial surface of the tympanic membrane

what area of the tympanic membrane is where the malleus connects to it?

21st fetal week - almost total ossification of malleus and incus and 24th week ossification of incus and stapes

when is the middle ear fully developed in gestation

cranial nerve 10 and 5

what cranial nerves innervate the Eustachian tube

mastoid bone

_____ is honeycombed air filled space located behind the pinna.

2-6 mm long

how long is the ossicular chain

ossicular chain

Three bones suspended in the middle ear via ligaments

Malleus

Incus

Stapes

To carry tympanic membrane vibrations to the inner ear

Lever action of the ossicular chain adds to signal intensity to overcome the impedance mismatch of the middle and inner ear

what is the function of the ossicular chain

impedence matching

Results in approximately 30 deciBel of gain which makes up for the 28 deciBel loss that occurs as the sound energy moves from air to liquid mediums

oval window

membrane-covered opening in the middle ear that connects to the inner ear. it helps transmit vibrations from the tiny bones of the middle ear to the fluid filled chamber of the cochlea.

round window

a small opening in the middle ear that connects to the inner ear. it allows fluid in the cochlea to move, which is essential for hearing

amplifier

Middle ear system is the _____ of the ear- one of the ways it does this is the rocking lever mechanism and the size difference between the tympanic membrane and the oval window

30 DB, 28 DB

The TM is a large vibrating surface as opposed to the oval window, a smaller surface. The lever action give ____ of gain to make up for ___of loss

Cranial Nerve III: Oculomotor

function is to open eyelids, eye movement (upward/ medial, upward/lateral, medial, downward/lateral)

cranial nerve V (trigeminal)

function is physical sensation and chewing movements

Cranial Nerve VII: Facial

function is facial muscle movement (except chewing muscles) and eyelid closing

cranial nerve VIII (auditory) (vestibulocochlear)

function is hearing and balance

Cranial Nerve X: Vagus

function is uvula (palate muscles) and swallowing

Cranial Nerve VII

what cranial nerve innervates the stapedius muscle

stabilizes the stapes and prevents excessive vibrations (located in the middle ear)

what does the stapedius muscle do

cranial nerve V

what CN innervates the tensor tympani muscle

it tightens the tympanic membrane, reducing its vibration amplitude thus reducing sound transmission into the inner ear. it pulls the handle of the malleus medially and then the malleus pulls on the TM and tenses it

what does the tensor tympani muscle do

conductive

disorders of the middle ear typically result in _____ hearing loss

2, ottitis media and otosclerosis

there are only _ disorders of the middle ear that could potentially cause sensory neural hearing loss.

70%

Nearly __of U S children experience otitis media before the age of 2 years

otitis media

infection of the mucus membrane lining of the middle ear

cholesteatoma

Occurs when skin is introduced into the middle ear cavity via a severely retracted T M

According to a *global disease burden modeling-based study* conducted in 2005, the incidence of acute otitis media (AOM) among adults aged 25 to 85 years is estimated to be between 1.5 to 2.3 percent.

However, the study does not provide information on the percentage of adults who experience hearing loss from otitis media.

what percent of adults experience hearing loss from otitis media

Individual: Poorly functioning eustachian tube, barotrauma, abnormal cilia of mucous membrane in the middle ear, anatomical abnormalities, age, race, socioeconomic factors, immune system

External: exposure to cigarette smoke and other fumes

what factors increase risk of otitis media

70%

otosclerosis is hereditary in __ of cases

otosclerosis

Originates in the bony labyrinth of the inner ear but is not clinically seen until it invades the middle ear resulting in a conductive hearing loss

otosclerosis

more often than not part of a disorder of the middle ear most likely causes conductive hearing loss, can become sensory neural if it reaches cochlea

vestibular

_____ is for balance and special orientation

cochlea

organ in the inner ear responsible for hearing

we have 3 but if 2 of them are working properly we can still function

how many parts of the inner ear do we need for balance and hearing?

25th

by the ___ week of gestation, our inner ear is completely formed

anguar

semicircular canals govern ___ movement

linear

utricle and saccule govern ___ movement

endolymph, perilymph

Utricle saccule and semicircular canals are filled with ___ and surrounded by ____

vertigo

When there is something going on with the vestibular system what do people experience