Eye Pathologies Flashcards
(24 cards)
For conjunctivitis, what is the likely cause if the discharge is purulent, thick and unilateral?
Bacterial (which is usually self-limitied, though antibiotic drops can shorten duration).
How do you treat keratitis?
You give ciprofloxacin eyedrops to treat against Pseudomonas.
What are the causes of red eyes that are emergencies?
Scleritis, uveitis, and keratitis.
What is the most common cause of conjunctivitis?
Staph. aureus
What is keratitis and what causes it?
It is infection and inflammation of the cornea, and most commonly results from bacterial infection (especially with Pseudomonas species) in contact lens wearers.
Bacterial (most common): contact lens, trauma.
Viral: herpes simplex (dendritic ulcers), varicella-zoster.
Fungal: vegetative trauma, tropical climates.
Acanthamoeba: contact lens, exposure to contaminated water.
Non-infectious / sterile: autoimmune, exposure keratopathy.
Clinical pearls:
Rapidly progressive, suppurative → bacterial.
Slow, feathery edges, trauma with plant material → fungal.
Severe pain out of proportion to clinical findings → acanthamoeba.
Dendritic ulcer → HSV keratitis.
What are the signs and symptoms of retinal detachment?
Sudden-onset monocular blindness (descrive as veil like), and retinal detachment is painles.
What are the symptoms of cataracts?
Blurred vision, sensitivity to glare, and difficulty with night driving.
What is the most common cause of red eye?
Conjunctivitis as infectious (viral or bacterial) or noninfectious (irritants, allergic).
For conjunctivitis, what is the likely cause if the discharge is watery?
Likely viral (specifically adenovirus).
What are the signs and symptoms of acute angle-closure glaucoma?
Extreme eye pain and a poorly reactive mid-dilated pupil. There may also be paralysis of extraocular muscles, vision changes, cloudiness, nausea and vomiting, etc.
What are the signs and symptoms of retinal detachment?
Sudden-onset monocular blindness (descrive as veil like), and retinal detachment is painless.
Term for when cornea and lens can perfectly focus light on the retina
Emmetropia
What is hyperopia?
Farsightedness
Cause of hyperopia
Axial length of eye is too short for the refractive power of the cornea and lens
Light focuses behind retina
What lenses can correct hyperopia
convex or converging
What is myopia?
nearsightedness
Causes of myopia
Axial length of the eye is too long given refractive power
Light focuses in front of retina
What lenses can correct myopia
Concave or diverging
What is astigmatism?
Abnormal curvature of cornea
What lenses correct astigmatism
corrected with cylindrical lenses
What is presbyopia?
Impairment of accommodation on nearby objects
Increasing age causes changes in lens curvature, decreased elasticity, decreased strength of ciliary muscle
WHich lens corrects presbyopia
Magnifying reading glasses
what is retinopathy of prematurity
abnormal proliferation of blood vessels that affects preterm infants due to a hypoxic biorth environment causing neovascularisation
mng of retinopathy of prematurity
stage 1- weekly opthal review
Immediate laser photocoagulation would be indicated for type 1 ROP (zone I, any stage with plus disease; zone I, stage 3 without plus disease; or zone II, stage 2 or 3 with plus disease).
Surgical vitrectomy would only be considered in advanced stages with retinal detachment (stages 4 or 5)
