chapter 17 Flashcards
sense organs: the eye & ear
accommodation
normal adjustment of the eye to focus on objectives from far to near
anterior chamber
the area behind the cornea and in front of the lens & iris
aqueous humor
fluid produced by the ciliary body and found in anterior chamber
biconvex
consisting of two surfaces that are round, elevated & curved evenly (lens of the eye)
choroid
middle, vascular layer of the eye, between the retina & sclera
ciliary body
structure surrounding the lens that connects the choroid & iris; controls shape of lens & secretes aqueous humor
cone
photoreceptor cell in the retina that transforms light energy into a nerve impulse; responsible for color & central vision
conjunctiva
delicate membrane that lines the undersurface of eyelids & covers anterior eyeball
cornea
fibrous transparent layer of clear tissue that extends over the anterior portion of eyeball
fovea centralis
tiny depression in the retina that is the region of clearest vision
fundus of the eye
posterior, inner part of the eye
iris
pigmented layer that opens and closes to allow more or less light into the eye
macula
yellowish region on the retina lateral to and slightly below the optic disc
optic chiasm
the point at which optic nerve fibers cross in the brain
optic disc (blind spot)
the region at the back of the eye where the optic nerve meets the retina
optic nerve
cranial nerve carrying impulses from the retina to the brain
pupil
central opening of the eye, surrounded by the iris, through which light rays pass
refraction
bending of light rays by the by the cornea, lens & fluids of the eye to bring the rays into focus on the retina
retina
light-sensitive nerve cell layer of the eye containing photoreceptor cells
rod
photoreceptor cell of retina essential for vision in the dim light and for peripheral vision
sclera
tough, white outer coat of the eyeball
thalamus
relay center of the brain
vitreous humor
soft, jelly-like material behind the lens in the vitreous chamber
aque/o
water
blephar/o
eyelid
conjunctiv/o
conjunctiva
cor/o
pupil
corne/o
cornea
cycl/o
ciliary body
dacry/o
tears, tear duct
ir/o & irid/o
iris
kerat/o
cornea
lacrim/o
tears
ocul/o & opthalm/o
eye
opt/o & optic/o
eye, vision
palpebr/o
eyelid
papill/o
optic disc
phac/o & phak/o
lens of eye
pupill/o
pupil
retin/o
retina
scler/o
sclera (white of eye)
uve/o
uvea
vitre/o
glassy
ambyl/o
dull, dim
dipl/o
double
glauc/o
gray
mi/o
smaller, less
mydr/o
widen, enlarge
nyct/o
night
phot/o
light
presby/o
old age
scot/o
darkness
xer/o
dry
-opia & -opsia
vision
-tropia
to turn
ALT
argon laser trabeculoplasty
AMD
age-related macular degeneration
HEENT
head, eyes, ears, nose & throat
IOL
intraocular lens
IOP
intraocular pressure
LASER
light amplification by stimulated emission of radiation
LASIK
laser in situ keratomileus
OD
right eye; doctor optometry
OS
left eye
OU
both eyes
PERRLA
pupil equal, round, reactive to light and accommodation
POAG
primary, open-angle glaucoma
PRK
photorefractive keratectomy
SLT
selective laser trabeculoplasty
VA
visual activity
VF
visual field
auditory canal
channel that leads from the pinna to the eardrum
auditory meatus
auditory canal opening
auditory nerve fibers
carry impulses from the inner ear to the brain
auditory tube (eustachian tube)
channel between the middle ear & nasopharynx
auricle (pinna)
flap of the ear; protruding part of external ear
cerumen (earwax)
waxy substance secreted by the external ear
cochlea
snail-shaped, spirally wound tube in the inner ear
eustachian tube
auditory tube
incus
second ossicle of the middle ear
labrinyth
maze-like series of canals of the inner ear
malleus
first ossicle of the middle ear
organ of corti
sensitive auditory receptor area found in the cochlea of the inner ear
ossicle
small bone of the ear
oval window
membrane between the middle ear & inner ear
perilymph
fluid contained in the labyrinth of the inner ear
pinna (auricle)
flap of ear
endolymph
fluid within the labyrinth of the inner ear
semicircular canals
passages in the inner ear associated with maintaining equilibrium
stapes
third ossicle of the inner ear
tympanic membrane (eardrum)
membrane between the outer &middle ear
vestibule
central cavity of the labyrinth, connecting the semicircular canals & the cochlea
acous/o, audi/o & audit/o
hearing
aur/o & auricul/o
ear
cochle/o
cochlea
mastoid/o
mastoid process
myring/o
eardrum, tympanic membrane
ossicul/o
ossicle
ot/o
ear
salping/o
eustachian tube
staped/o
stapes
tyman/o
eardrum, tympanic memebrane
vestibul/o
vestibule
-acusis & -cusis
hearing
-meter
instrument for measure
-otia
ear condition
-metry
process of measurement
-phobia
fear
-plegic
paralysis, palsy
AD
right ear
AOM
acute otitis media
AS
left ear
EENT
eyes, ears, nose & throat
ENG
electronystagmography
ENT
ears, nose & throat
ETD
eustachian tube dysfunction
PE tube
pressure-equalizing tube
SOM
serous otitis media
pathway of light rays to the visual region of the brain:
cornea -> anterior chamber & aqeous humor -> pupil -> lens -> vitreous chmaber & vitreous humor -> retina -> optic nerve fibers -> optic chiasm -> thalamus -> cerebral cortex (occipital lobe)
anisocoria
condition of pupils of unequal size
cycloplegic
pertaining to paralysis of ciliary muscles, which would result in dilation or enlargement of the pupil
palpebral
pertaining to the eyelid
mydriasis
condition of enlargement of the pupil
miosis
condition of constriction of the pupil
papilledema
swelling in the region of the optic disc
photophobia
condition of sensitivity to (“fear of”) light
scotoma
blind spot; area of darkened (diminished) vision surrounded by clear vision
corneal ulcer
fibrous layer of clear tissue over the front of the eyeball has a defect resulting from infections
uveitis
inflammation of the vascular layer of the eye (iris, ciliary body & choroid)
xerophthalmia
condition of dry eyes
hemianopsia
absence of vision in half of the visual field
exotropia
eye abnormally turns outward
ophthalmologist
medical doctor who treats diseases of the eyes
optometrist
nonmedical professional who can examine eyes & prescribe glasses
optician
nonmedical professional who grinds lenses and fits glasses
aphakia
absence of the lens of the eye
esotropia
eye abnormally turn inward
amblyopia
decreased (dim) vision; lazy eye (resulting from strabismus & uncorrected refractive errors in childhood)
hyperopia
farsightedness
presbyopia
decreased vision at near, resulting from increasing age
myopia
nearsightedness
nyctalopia
night blindness; decreased vision at night
diplopia
double vision
astigmatism
defective curvature of the lens and/or cornea leading to blurred vision
in the myopic eye, light rays don’t focus properly on the retina, either the eyeball is too long or the refractive power of the lens is too strong so that the image is blurred & comes to a focus in front of the retina, this type of lens is correct this refractive error?
concave lens
in the hyperopic eye, the eyeball is too short or the refractive power of the lens is too weak, so that the image is blurred & focused in the back of the rent, the type of lens used to correct this refractive error?
convex lens
miotic drug
drug that constricts the pupil of the eye
mydriatic drug
drug that dilates the pupil of the eye
diabetic retinopathy
retinal microaneurysms, hemorrhages, dilation of retinal veins & neovascularization occur secondary to an abnormal endocrine condition
retinal detachment
two layers of the retina separate from each other
strabismus
abnormal deviation of the eye occur (esotropia & exotropia)
cataract
clouding of the lens causes decreased vision
macular degeneration
loss of central vision caused by deterioration of the macula of the retina
hordeolum (stye)
localized, purulent infection of a sebaceous gland in the eyelid
chalazion
small, firm, cystic mass on the eyelid; formed as a result of chronic inflammation of a sebaceous gland
glaucoma
increased intraocular pressure damages the retina & optic nerve
retinitis pigmentosa
pigmented scarring forms throughout the retina
nystagmus
repetitive rhythmic movements of one or both eyes
stroke (hemianopsia)
loss of half of the visual field caused by a stroke affecting the left visual cortex
phacoemulsification
ultrasonic vibrations break up the lens & the fragments are aspirated from the eye
visual activity acuity test
test of clearness of vision
tonometry
measurement of tension or pressure within the eye, glaucoma test
laser photocoagulation
high-energy light radiation beams are used to stop retinal hemorrhaging
LASIK
laser removes corneal tissue (sculpts it) to correct myopia
fluorescein angiography
intravenous injection of dye followed by photographs of the eye through dilated pupils
scleral buckle
suture of a silicone band to the sclera to correct retinal detachment
visual field test
test to measure central & peripheral vision (area within which objects are seen) when the eyes are looking straight ahead
vitrectomy
removal (and replacement) of diseased fluid in the chamber behind the lens of the eye
opthalmoscopy
visual examination of the interior of the eye after dilation of the pupil
slit lamp microscopy
use of an instrument for microscopic examination of parts of the eye
keratoplasty
corneal transplant surgery
transmission of sound waves to the brain from the outer ear:
pinna (auricle) -> external auditory canal -> tympanic membrane -> malleus -> incus -> stapes -> oval window -> cochlea -> auditory liquids & receptors -> auditory nerve fiber -> cerbral cortex
otoscope
instrument to examine the ear
salpingopharyngeal
pertaining to the auditory tube & throat
otopyorrhea
flow of puss from the ear
audiometer
instrument to measure hearing
presbycusis
deafness due to old age
microtia
small ear
otitis media
inflammation of the middle ear (ear infection)
vertigo
sensation of irregular or whirling motion either of oneself or of external objects
meniere disease
disorder of the labyrinth marked by elevation of ear fluids & pressure within the cochlea (tinnitus, vertigo & nausea result)
otosclerosis
hardening in the bony tissue of the ossicles of the middle ear
tinnitus
sensation of noises (ringing, buzzing, whistling, booming) in the ears
cholesteatoma
collection of skin cells & cholesterol in a sac within the middle
suppurative otitis media
inflammation of the middle war with bacterial infection & pus collection
acoustic neuroma
benign tumor arising from 8th cranial nerve, causing tinnitus, vertigo, dizziness & decreased hearing
deafness
loss of ability to hear
electronystagmography (ENG)
a test of balance
PE tube process
ventilating tube placed in the eardrum
photopsia
bright flashes of light
floaters
vitreous clumps
pneumatic retionpexy
a gas bubble is injected in vitreous cavity to help reattach the retina
enucleation
removal of the entire eyeball
cochlear implant
a surgically implanted device that allows sensorineural hearing-impaired persons to understand speech
ear thermometry
body temp. measured with infrared radiation from the eardrum
tuning fork test
hearing tests using a vibrating fork
rinne (tuning fork test)
fork is placed against the mastoid bone & in front of the auditory meatus
weber (tuning fork test)
fork is placed on the center of the forehead; normal hearing has equal loudness in both ears