opthalmology Flashcards
purpose of vitrous humor
keep that retina in place, and maintain shape of eye
macula
responsible for about 90% of vision
refeactive error
near, far, stigmatism, and presbyopia
near sightedness
focus is anterior to retina
far sightedness
focus is posterior to retina
stigmatism
miss shapped eye, think football like. focus is all over the place
presbyopia
cilliary muscle looses strength, cant focus on near objects. people usually get reading glasses for this.
eye exam
visual acuity, visual fields, ocular otility, pupils external exam, fundoscopic exam
acuity
use an eye chart, one eye at a time .
visual fields
look at objects in various places, while focusing on a single spot.
motility
follow finger… eyes track together, cn3,4,and6
pupil
shine light in pupil. make sure it constricts, make sure round, symmetric, etc
external exam
use a pen light to identify the eyelide, clear cornea, conjunctiva, and anterior chamber
fundoscopic exam
need a dilated pupil, check red reflex (the reflected light should be red off retina), see optic nerve, and see retina
red eye
unilateral and bilateral causes
conjuntivitis
unilateral, pink eye, viral or bacterial. eyes glued shut in morning.
viral - more common. usually post upper respiratory infection. often adenovirus. eye is red, watery. Monitor hand hygiene.
Bacterial - purplent. Staph aureus and strep pheumoniae, look for yellow discharge.
iritis
unilateral. inflammation of iris. pupil looks deformed due to inflammation. blurred vision, pain, photophobia. usually 20-40 age demographic.
corneal abrasion
unilateral. scratch of the cornea. lots of pain, blurred vision, tearing
mild uses ointment, tears
severe requires tap eye closed for a day
corneal ulcer
unilateral. infction of corneal stoma. S.aureus, pseudomonas. dont sleep with contacts. people have dry eyes, cn7 palsy (cant blink), decreased vision, lots of inflammation
look for white in cornea
corneal foreign body
unilateral. material lodged in the surface of cornea, could also be on inside of eyelid
dry eye
bilateral. lack of tears, feels like a foreign body, worsens when reading or computer work. Happens in low humid places
from body not producing tears, or producing tears and the tears evaporate too quickly.
not enough - anti-histamines, pain meds, anti-depressants, lupus and other auto immune
dry eye tests
shimmer’s test - strips of paper and see how far tears travel
corneal staining - fluoresces condenses in to dry areas
allergic conjunctivitis
bilateral, seasonal, itchy eyes, history of allergies
herpes simplex
unilateral, hsv1, corneal epithelium. get super weird branching dendrite pattern using fluorasine.
can get corneal scar.
herpes zoster
unilateral, v1 distribution, will see chicken pox/scales on skin. if rash on nose, assume eye involvement.
pterygium
unilateral. lots of UV light. is a benign vascular growth on surface f cornea.
subconjunctival heme
ruptured blood vessel. blood in the white of eye. anti-coags are at greater risk
angle closure glaucoma
common is asians, 60-70, hyperopia. Sever eye pin. nausea vomiting. blurred vision, halos.
pupil is partially dilated, and cornea is hazy. eye will feel firm due to IOP. aqueous fluid in cilliary chamber flows into space behind iris, iris is adherent to lense, this pressure.
use a laser create a hole, allows fluid to move.
open angle glaucoma
progressive disease. IOP. causes patients to loose peripheral vision. puts pressure on optic nerve, nerve appears enlarged.
cataracts
clouding of lens. progressive decline.
trauma, radiation, diabetes, age.
