Eyes Flashcards
outer layer of the eye is called
fibrous sclera
Middle layer is called
vascular choroid
middle layer includes
pupil, lens, anterior chamber, iris, and ciliary body
Inner layer is called
nervous retina
inner layer contains
optic disc, macula, retinal vessels, vitreous body
cornea function
covers iris and pupil, refracts media of the eye
choroid function
prevents light from reflecting inside, delivers blood to retina
ciliary body function
changes curvature of lens
iris contracts during
bright light and for near vision
lens function
keeps viewed object in focus on the retina
retina function
changes light waves into nerve impulses
corneal light reflex or hirschberg test
shine light on forehead 12 inches away, the reflection should be seen same in each eye
nystagmus (shaking) is normal in relation to
newborns
myopia
nearsightedness, light rays focus in front of retina
myopia causes
globe is too long, cornea is curved
hyperopia
farsightedness, light focuses behind retina
hyperopia causes
globe is too short, cornea is too flat
presbyopia
stiffening of the lens
astigmatism
distortion and blurry vision
astigmatism causes
cornea is shaped like a football
strabismus
misalignment of eye axes
esotropia
eye turns in
exotropia
eye turns out
hypertropia
eye turns up
hypotropia
eye turns down
exophthalmos
eyes protruding outwards
ectropion
lower lid is loose
entropion
lower lid rolls inwards
