Eye (Mehrhoff) Flashcards
(45 cards)
Hordeolum
an acute purulent soft mass in the periorbital region; if does heal properly can become a chalazion
If a hordeolum doesn’t heal properly, what can it turn into?
chalazion
Chalazion
chronic lipogranuloma from an obstructed meibomiam gland; roundish, firm lesion painLESS lesion within the tarsal plate.
Sebaceous Adenocarcinoma of the eyelid
small, rubbery/firm nodule on upper eyelid (can mimic chalazion); slow-growing tumor with atypical epithelial cells; tends to metastasize; elderly and female predominate; yellowish appearance is a suspicious sign
What is a sign that can help you distinguish a Sebaceous Adenocarcinoma of the eyelid from a Chalazion?
yellowish appearance - more towards Sebaceous Adenocarcinoma of the eyelid (also look for macaronis - loss of eyelashes)
Basal cell carcinoma
most common malignant lesion of the eyelid (90%); flesh-colored to pearly raised nodule with “rolled edges”; rarely metastases; peak age of 70 yrs
What is the most common malignant lesion of the eyelid?
Basal cell carcinoma
A description of a flesh-colored to pearly raised nodule with “rolled edges”on the eyelid should make you suspect what?
Basal cell carcinoma
Squamous cell carcinoma
most common skin cancer; predominately amongst dark-skinned individuals; erythematous pink nodules with overlying scale or crust; may find “horn pearls”
What is the most common skin cancer?
Squamous cell carcinoma
A description of erythematous pink nodules with overlying scale or crust and some “horn pearls” around the eyelid should make you suspect what?
Squamous cell carcinoma
Melanoma of the eyelids
ABCDE’s of melanoma (asymmetry, border irregularities, color with black and blue hues, diameter >6mm and change in the lesion over time); looks for loss of eyelashes; associated with high mortality
When light passes through the cornea and the lens, what is the orientation of the image?
Inverted and reversed (refracted)
Hyperopia
farsightedness; corrected with convex lens
Myopia
nearsightedness; corrected with concave lens
Astigmatism
abnormal curvature of cornea; corrected with cylindrical lens
Cataracts
painless opacification of the lens; nuclear is most common type - nuclear sclerosis increases the lens refraction and leads to increased myopia and decreased hyperopia
What is the most common type of cataracts?
nuclear cataracts
Explain the flow aqueous humor?
posterior chamber to pupil and then can go down one of two routes:
1. trabecular route - trabecular meshwork at angle of anterior chamber to scheme’s canal
2. uveoscleral route - uveal meshwork at ciliary muscles to the suprachoroidal space
both routes lead to the episcleral veins
What are two structures that are compressed due to increased intraocular pressure (IOP) seen in glaucoma?
- optic nerve - leads to cupping
- vessels - ischemia of the optic nerve
Glaucoma
group of optic neuropathies with cupping that lead to visual field defects due to obstruction of aqueous humor drainage; most cases lead to increased intraocular pressure (IOP)
Open-angle glaucoma
“silent thief of sight” - no pain unless IOP is very high; resistance of AH flow in the trabecular meshwork (obstruction)
What is a major risk factor to neovascular glaucoma?
type II diabetes with proliferative stage of diabetic retinopathy
Retinal detachment
separation of the neurosensory retina from the RPE; check for “floaters and flashes” in the patient history; can be a description of “curtain drawn down”; there is no pain and fundoscopy can show crinkling of retina; is a surgical emergency