Audiology Exam 2

temporal bone

where the entire auditory system housed

attached to parietal, frontal, mandible

parietal

top/side of skull

occipital

back of skull

frontal

front of skull

zygomatic

sinuses behind bone

maxilla and mandible

jaw

head injury damage likelihood

frontal, temporal, parietal

seen more in younger people

zygomatic process

attaches temporal bone to skull and zygomatic bone

temporal squama (squamous)

where outer ear is located

flat part of temporal bone

outermost part of temporal bone

tympanic part

where middle ear is located

mastoid

right behind pinna (right above tympanic part)

petrous part (pyramid)

where inner ear is located

deepest part of temporal bone

internal auditory canal

where facial and auditory nerve exits to brain

semicircular canals

balance

pinna

antenna, funnels sound, picks up sound

most visible part of ear

enhances high pitched sounds

leads into ear canal

made of cartilage (soft connective tissue) (all except lobe)

ear lobe

part of pinna with no cartilage (just skin) (bottom of ear where piercing is)

helix

enfolded part of pinna made of cartilage

tragus

part that can block ear canal

made of cartilage

concha

bone like depression, concavity

made of cartilage

directs sounds into ear canal

ear canal

open at one end, closed at other (like human flute that produces standing waves)

resonator (colors sound)

based on size of ear canal, standing waves change dramatically (Boyle’s Law)

• small (1/2 maybe, like 1 a figure)

• large (2-3 cycles of wave like 1 d figure)

so same sound looks different in different ear canals based on shape and size (each person hears differently because of unique size and shape of ear canal)

most cartilage, some bone

outer 1/3 of ear canal

has many glands (more likely for cerumen- sebaceous glands)

• ear canal prefers moisture, poke inside ears damage sebaceous glands

number of hair follicles + cerumen keeps foreign objects out

inner 2/3 ear canal

bony

goes through temporal bone

Osseocartilaginous junction

where two portions of external auditory canal meet

small bend where cartilaginous and bony part meet

size of ear canal

children- angles downward (more acute angle)

average adult length- 1 inch slight upward angle (depends males female size)

9mm height, 6.5 mm width

healthy ear canal

pink in color (red = inflamed)

bent (s shape)

ear drum (tympanic membrane)

soft skin tissue

concave disk like structure

pearly gray to pink in color

pars flaccida

top part of ear drum, not very rigid

lacks middle layer of fibrous connective tissue (why more flexible)

outer skin and inner mucous

pars tensa

bottom part of ear drum, more rigid

has all 3 layers (outer skin, inner connective tissue, inner mucous membrane)

outer layer of ear drum

same skin as external auditory canal

middle layer of ear drum

rough, fibrous connective tissue

contributes to ear drum mobility 

inner layer

completely lined with same mucous membrane lining inner ear

protective, moist, prevents foreign bodies

temperature and humidity of ear drum

constant

busted ear drum

perforation in part of ear drum

Audiologist can’t do anything; must go to ENT

pain associated

large/central perforation

hole in pars tensa

more common

more HL

tears through all three layers

marginal/attic perforation

hole in pars flaccida

less common

can produce collection of squamous epithelium that can grow into middle ear and give tumor like appearance

which small bone is attached to the ear drum?

malleus; manubrium (handle) specifically

pulls ear inwards (reason for concavity)

C shape

umbo

deepest point of concavity in ear drum

where cone of light emerges

cone of light

indicates healthy ear drum

disappears in ear infection, perforations

reflection of light from otoscope on ear drum

otoscope

easiest way to view ear drum

attach plastic speculum to metal point

look for foreign objects, occlusion or impacted wax, lesions, scrapes, cuts on external ear canal

otoscopy

procedure used to explore ear canal

BRIDGING- little finger against cheek, thumb giving support (way of alerting person not to move in eval)

head tilt for view

pull top of pinna backwards and upwards (children - down and back)

person’s ear level

video otoscope

show ear drum on screen through connection to video monitor

way to visualize in different way

microscopy

microscope to illuminate ear canal

many ENTs prefer

more control, better view of ear canal

probe microphone

measure output of hearing aid based on ear canal

Knowles leader of microphones and receivers

hearing aid receiver issues

ear wax, blood in ear canal, ear infection

head mirror

use to shine light in nose, ear, throat

speculum

attached to otoscope (plastic cover)

forceps

tweezers

post nasal mirror

bent mirror; visualize sinuses by shining light into them

indirect laryngoscopy 

visualize vocal folds 

straight mirror, put inside mouth

preauricular sinus

developmental embryological defect

open channel for infection into ear canal (small hole in front of pinna)

doesn’t produce HL on own

relatively harmless

surgery to fix (if think could lead to infection)

preauricular tag

extra skin growth in front of pinna

most of time harmless and no fixing necessary

no HL

anotia

absent pinna

microtia

small pinna

anotia/microtia characteristics

lack of developed pinna

usually just one side

severity varies

frequent association with congenital abnormalities

conductive HL (bc no pinna, could create through plastic surgery)

surgical reconstruction- bone anchored or bone conduction hearing aids (in temporal bone)

atresia

blocked ear canal opening

congenital malformation 

can coexist with microtia

conductive of sensorineural HL

stenosis

narrowing of ear canal

collapsed ear canals

slightly different from atresia

infants and elderly at risk from weight of headphones

• weak cartilage

haemotoma

cauliflower ear

result of blunt trauma to ear

blood collects below cartilage

• untreated, destruction of cartilage

• pressure bandage drains blood from ear to prevent

treatment= aspiration, pressure dressing, antibiotics

cerumen

ear wax

epithelial migration of skin tissue leading to buildup of keratin (dead skin tissue)

can then get infected

desquamated epithelium mixes with secretions of glands

dry or moist

older individuals collect more bc migration slows with age and more hair in older males

impacted cerumen

clogging ear canal

at risk- constant Q tips

cleaning cerumen

lighted ear curette (requires training)

debrox (use tepid water and point upwards)

external otitis

inflammation of ear canal

swimmer’s ear

fungal infection of ear canal

inflammation of ear canal skin

bullous myringitis

swelling boil on ear drum from untreated external otitis

otomycosis

fungal infection of ear canal, typically seen in swimmers

fungus

organic living material growing on dying tissue

needs water to grow

treatment- antifungal

virus

dead cells that replicated inside host (strand of RNA)

go from one host to other, more contagious

treatment- antivirals (prevents replication of virus)

bacteria

living material

has own DNA and can grow outside host

uses host DNA to be stronger

antibiotics only way to cure

gram positive bacteria

cell wall, rigidity

antibiotics- penicillin, amoxicillin, cloxacillin (destroys outer layer of bacteria)

gram negative bacteria

don’t have cell wall but strong

antibiotics- aminoglycosides (broad spectrum)

ear, lung, throat, gut infections

antibiotic resistance

frequent exposure to antibiotics can cause body immunity

most common infections

bacteria and virus

nose and mouth easiest places

ear infection travels from nose through Eustachian tube

traumatic perforations

blow to ear

irregular edge of perforation of ear drum

bleeding in ear canal

conductive loss

ear pain

spontaneous healing (no treatment) bc of epithelial tissue

• only thing to do -prevent water getting in to get external otitis with cotton ball