EYES & EARS anatomy etc...

bony cavity that houses the eyeball, eye muscles, nerves and blood vessels

• 1: sclera
• 2: cornea
• 3: choroid layer

white outer layer of the eyeball

anterior portion of the eye, where the sclera forms a transparent dome structure

avascular, but has nerve endings with pain fibers

protects the front part of the eye from injury and is the first structure of the eye that refracts light rays

lies behind the sclera and has blood vessels

Ciliary body: (muscle) anterior portion of the choroid

• iris: also anterior portion of eye.
• colored portion of the eye

lines the poster 2/3 of the eyeball

contains rods (light) and cones (colors)

(part of retina) depression near the center of the retina.

area with sharpest vision (lots of cones)

Macula: yellowish surrounding of the fovea.  lots of cones here too

keratorrhexis

Used to correct vision

shallow, bloodless, hairline, radial incisions are made using a laser in the outer portion of the cornea...this allows the cornea to flatten and helps to correct nearsightedness

opening in the center of the iris

controls amount of light entering the eye by contractions and dilations

constriction of the pupil permits a sharper near vision

light sensitive molecules that convert light energy into electrical impulses.

where retinal nerve fibers unity and cut across through the wall of the eyeball as the optic nerve

optic disk has to rods or cones (blind spot)

ophthalmoplegia

thin mucous-secreting membrane that lines the interior surface of the eyelids and the exposed anterior surface of the eyeballs

surgical procedure to remove wrinkles from the eyelids

excessive skin around he upper eyelids may cause a decrease or lack of peripheral vision

condition in which objects that are not red appear to be red

condition in which objects that are not yellow appear to be yellow

double vision

both eyes are not in focus

can occur with brain tumors, strokes, head trauma, and migraine headaches

nearsightedness

if the eyeball is too long, the visual images falls in front of the retina, causing difficult seeing objects that are far away

farsightedness

occurs when the lens focuses the visual image beyond the retina causing difficulty in seeing objects that are close

common after a stroke, because the muscles leading to the eyelids become paralyzed

located above the outer corner of each eye

these glands produce tears, which keep the eyeballs moist

collects and drains tears into nasolacrimal duct

pain in the tear gland

inflammation of a tear gland