Chapter 11: Ears and Eyes Flashcards
external ear
auricle, external auditory canal
middle ear
from tympanic membrane to oval window; malleus, incus, stapes
inner ear
series of fluid filled passages knkown as labyrinth
cochlea
front portion of inner ear
vestibular apparatus
rear portion of inner ear
external ear produces
cerumen - filter that trapps dust and foreign substances
indented shape of auricles act as
effective receivers of sound waves
soundwaves travel through auditory canal and strike tympanic membrane which
vibrates the ossicles
organ of Corti
sensitive auditory receptor area in cochlea
ot.o
ear
myring/o, tympan/o
tympanic membrane
labyrinth/o
labyrinth
acous/o, audi/o, audit/o
hearing
mastoid/o
mastoid process
salping/o
tubes
-acusis
hearing
-opsia
vision
-stenosis
narrowing
-tropia
turning
otitis media
accumulation of fluid in middle ear, earache
serous otitis media
chronic may develop from acute condition, or result from overgrowth of adenoidal tissue or chronic sinus infections
suppurative otitis media
caused by introduction of pyogenic microorganisms into middle ear
PE tubes
pressure equilizer tubes
conductive hearing loss
due to impairment in transmission of sound
meniere disease
disorder of unknown etiology within labyrinth of inner ear that can lead to hearing loss
otosclerosis
progressive deafness due to ossification in bony labyrinth of inner ear
presbycusis
impairment of hearing that results from aging process
tinnitus
ringing or tinkling noise heard constantly or intermittently in one or both ears
vertigo
sensation of moving around in space or feeling of dizziness or spinning
rinne
evaluates bone versus air conduction of sound (tuning fork test)
webber
evaluates bone conduction in both ears at same time (tuning fork test)
myringotomy
incision of tympanic membrane and insertion of PE tube to treat chronic otitis media
eye outer layer
fibrous tunic: scelra, cornea, conjunctiva
middle eye layer
vascular tunic (uvea): choroid iris, cilliary body, lens
cilliary body
externsion of choroid, attaches to suspensory ligaments that hold the lens in place behind the iris
innermost layer or eye
sensory tunic - double layered retina
retine composed of
optic disk, optic nerve, rods and cones
lacrimal gland
produces tears
sclera
white opaque outer surface that protects inner structure of eye and helps maintain its sahape
cornea
transparent layer allows light to enter and refracts light
conjunctiva
delicate transparent mucous membrane that covers insides of eyelid
choroid
supplies blood to entire eye
rods
detect shades of gray at all levels of light
cones
detect color but operate only at high light levels
optic disk
area in retine where nerve fibers and blood vessels enter and exit
optic nerve
cranial nerve II - carries impulses from retina to areas of brain responsible for processing visual information
aqueous humor
watery fluid continuously produced by ciliary body
aqueous humor drains into
canal of Schlemm, circular channel around iris, absorbed into veins and taken away by blood
vitreous humor
gel-like substance that helps maintain shape of eye; fills posterior cavity
extraocular muscles
control eye movement, attached to sclera by tendons
ocul/o, opthalm/o
eye
blephar/o
eyelid
opt/o
eye, vision
retin/o
retina
choroid/o
choroid
irid/o
iris
corne/o
corneo
dacry/o, lacrim/o
tear, lacrimal apparatus duct, sac, gland
dipl/o
double
kerat/o
horny tissue, hard, cornea
cor/o, core/o, pupill/o
pupil
-opia, -opsia
vision
-ptosis
prolapse, downward displacemnt
-tomy
incision
-tropia
turning
cataract
opacity or clouding of lens or its surrounding membrane
IOLs
intraocular lenses that are surgically implanted
two common surgical methods to remove cataracts
phacoemulsification, intracapsular and extra capsular extraction
strabismus
visual defect in which both eyes cannot be directed to focus simultaneouslu on same object
esotropia
eye turns inward, cross eye
exotropia
eye turns outward - wall eye
glaucoma
accumulated fluid pressure within eye damages retina and optic nerve - blindness
macular degeneration
macula, small area of retine responsible for central and color vision - degenerates
dry macular degeneration
slow and progressive loss
wat macular degeneration
sudden onset
hordoleum
stye - inflammatory infection of sebaceous glands of eyelid
achromatopsia
congenital deficiency in color perception
astigmatism
defective curvature of the cornea and lens that causes light rays to focus unevenly over retina
conjunctivitis
inflammation of conjunctiva - pinkeye
diabetic retinopathy
occurs in people with diabetes - scarring and eventual loss of vision
photophobia
unusual intolerance and sensitivity to light
retinal detachment
separation of retina from choroid
tonometry
detects glaucoma by measuring increased IOP
visual acuity test measured with use of
snellen chart; person is 20 feet from chart
miotics
causes pupils to constrict, increases outflow of eye fluid
mydriatics
causes pupils to dilate