Cornea, Iris and Lens Flashcards
Corneal arcus senilis
common in elderly
-whitish area around cornea (opacification)
-not pathologic
may be seen in severe hypercalcimia
corneal abrasion
very painful
- typically has history of trauma
- need to use fluoroscene stain, because it is not visible with the naked eye
- superficial, epithelial layer
which CN innervates the cornea?
ophthalmic branch of CN V
corneal ulcer
very painful
long onsetting (a few days)
deep into the stroma
-usually related to an infectious process (herpes)
-opaque and can be seen with the naked eye
hypopyon (hypopion)
pus layers behind the cornea
- corneal ulcer
- iritis
- result of an inflammatory process in the anterior of the eye
corneal scar
opaque patch that is secondary to chronic ulceration (abrasions typically don’t scar)
iritis
inflammation of the iris
- typically very painful
- inflammation extends to the limbus
- associated with other inflammatory conditions (RA, IBS)
hyphema
blood in the anterior chamber
- most common cause is trauma
- will stain to stain
- can cause severe tension in the eye
cataract (peripheral)
opacification of the lens
- common complaint is difficult night vision
- treatment is surgical correction
- more at risk of getting it if you have high exposure to UV lights
- no. 1 cause of blindness world wide
glaucoma
intraocular pressure
-pressure begins in the anterior portion of the eye
open-angle glaucoma
angle of canal is open, but flow through trabecular meshwork is slow (overproduction or poor drainage)
- chronic problem
- treatment, create less aqueous humor or allow more flow
- not painful
- high blood pressure of the eye
closed-angle glaucoma
iris contracts, angle closes and fluid can’t flow out
- acute onset
- painful, red eye
- headache, nausea, vomiting
- mid-dilated fixed pupil
how does glaucoma cause visual loss?
increased pressure in the anterior of the eye over time can compress the retina and optic disc thereby impairing vision
glaucomatous cupping
pressure spreads the optic disc out and you see a big wide optic disc
hirshberg test
test of corneal light reflection
-normally is slightly nasal to the center of the cornea
esotropia
corneal light reflection is positioned lateral to the center
- eye deviates toward the nose
- convergent strabismus
- light reflection looks more lateral