CH. 16 Assessing the Eyes Flashcards
Chapter 16
eyelids
skin/two muscle types. protect eye from foreign bodies.
eyelashes
stiff hair projections, filter dust/dirt from air that enters eye
conjunctiva
thin transparent continuous membrane. palpebral, bulbar - protect eye/allow inspection of the underlying tissue
Palpebral conjunctiva
lines inside of eyelids
Bulbar conjunctiva
covers most of anterior eye
Lacrimal apparatus
glands/ducts that lubricate eye. lacrimal gland produces tears - from glands to puncta, lacrimal canal, lacrimal sac, nasolacrimal duct, nose (ex: if crying, tears drain into nose)
Extraocular muscles
six muscles move in six directions. four rectus, two oblique. attached to outer surface of each eyeball, associated w/ CN 3,4,6
External structures of eye
eyelids, eyelashes, conjunctiva, lacrimal apparatus, extra ocular muscles
Internal structure/layers of the eyes
external = sclera/cornea. middle = iris/ciliary body, choroid. inner = retina extends to ciliary body anteriorly, receives visual stimuli
Choroid layer
vascular layer of eye, provides oxygen/nourishment to inner aspect of eye. prevents light from reflecting internally, anteriorly continuous w/ ciliary body/iris
Sclera
dense protective white covering, physically supports internal eye structures
Cornea
permits entrance of light, nerve endings, responsive to pain/touch. corneal reflex in response to cotton wisp touching eye
iris
circular disc of muscle used to control amount of light coming into eye, color, center is pupil
Ciliary body
muscles that control thickness of lens, focuses on images seen
lens
biconvex, transparent, avascular encapsulated structure immediately posterior to iris. refracts light into retina in order to see/focus on near/far objects
retina
receives visual stimuli/sends to brain. numerous layers of nerve cells - rods, cones. optic disc, retinal vessels
rods
highly light sensitive, black/white vision, function in dim light
Cones
function in bright light, sensitive to color
optic disc
where optic nerve enters eye, can be seen w/ ophthalmoscope, normally round/oval
retinal vessels
seen w/ ophthalmoscope, venules/arterioles. macula w/ many cones
visual field
where light rays strike cornea and are transformed into nerve impulses interpreted by brain
Pupillary light reflex
causes pupils to immediately constrict when exposed to bright light
accommodation
functional reflex allowing eyes to focus on near objects
Present health concern (vision)
visual difficulties/recent change, spots/floaters, halos/rings around lights, trouble seeing at night, double vision (diplopia)
Present health concern (eyes)
pain/itching, pain w/ bright lights (photophobia), redness/swelling, excessive watering (which eye) - epiphora, eye discharge
epiphora
excessive tearing, caused by exposure to irritants or obstruction of lacrimal ducts
Personal health history
problem w/ eyes or vision, eye surgeries, past eye treatments, medications, last eye exam, macular degeneration (amsler test), glasses/corrective lens, tested for glaucoma? family history w/ eye problems
Amsler Test
evaluates visual field defects. eye level, cover one eye, fix on center black dot, see if any lines are distorted, mark defect on chart, test eyes separately (same distance every time). tell provider about distortion, graying, blurring, or blank spots