High yield exam cram Flashcards
What does Mydriasis mean?
Dilated pupils
What does mitosis mean?
Constricted pupil
Which gives colour vision, rods or cones?
Cones (cones for colour)
What is the function of Timolol (Beta blocker)?
Reduces the production of aqueous humour
What is the function of Dorzolamide (carbonic anhydrase inhibitor)?
Reduces the production of aqueous humour
What is the function of Acetazolamide (carbonic anhydrase inhibitor)?
Reduces the production of aqueous humour
What is the function of Brimonidine (sympathomimetics)?
Reduce production of aqueous humour and improve uveoscleral outflow
What is the function of Lantoprost (prostaglandin analogues)?
Increase uveoscleral outflow
What is the function of Pilocarpine (muscarinic agonist)?
Pupil constriction and ciliary muscle contraction
What is the function of Anti VEG-F?
Targets VEG-F which stimulates formation of new blood vessels
What is the function of Chloramphenicol eye drops?
Antibiotic
What is the function of Fusidic eye drops?
Antibiotic (Used instead of chloramphenicol in pregnancy)
What is the function of Sodium cromoglicate?
Mast-cell stabiliser, reduces allergic response
What is the function of Cyclopentolate?
paralyses and dilates the pupil to relieve ciliary spasm
What is the function of Atropine (eye drops?)
paralyses and dilates the pupil to relieve ciliary spasm
What is the function of Phenylephrine eye drops?
Differentiates scleritis and episcleritis (doesn’t have any effect in scleritis)
Describe the layers of the eyeball from most superficial to deepest
What is the most common bacterial cause of corneal infection (keratitis)
S. Aureus
What is the most common viral cause of corneal infection (keratitis)
Herpes
How should corneal infection (keratitis) be managed?
Antibacterial/viral/fungal eye drops. Stop using contact lenses until healed
What are the two main causes of conjunctivitis?
infective or allergic
How long does an episode of conjunctivitis usually last?
1-2 weeks (usually self limiting)
How should conjunctivitis be managed?
Chloramphenicol antibiotic drops (fusidic acid if preg), hygiene, no lenses, no towel sharing!
What is anterior uveitis?
Inflammation of the iris/ciliary body or chorioid
How does anterior uveitis present?
Pain, photophobia, epiphora (excessive tears), redness, small & irregular pupil, hypopyon
What causes anterior uveitis?
idiopathic
or
secondary to systemic autoimmune diseases (ulcerative colitis), sarcoidosis, infections, trauma, or drug reactions
How is anterior uveitis managed?
Topical corticosteroids & cycloplegic agents (tropicamide or homatropine) to reduce ciliary spasm
What causes episcleritis?
Who knows (unknown aetiology)
What diseases have an association with episcleritis?
rheumatoid arthritis and IBD
How does episcleritis present?
Localised, red area on the white part of the eye
PAINLESS!
How is episcleritis managed?
Leave it alone to self resolve within a few weeks
What causes scleritis?
autoimmune disease (rheumatoid arthritis and vasculitis) and infection
How does scleritis present?
Severe pain (Scleritis = Sore), swelling and redness
What happens if scleritis is left untreated?
Vision loss
How are scleritis and episcleritis differentiated?
Differentiate with phenylephrine eye drops (scleritis doesn’t react to the drops)
Scleritis is sore
What is the difference between periorbital cellulitis and orbital cellulitis and how are they differentiated from one another?
Periorbital cellulitis = around the eye
Orbital cellulitis = behind orbital septum
Differentiate with a CT scan
How does Subconjunctival Haemorrhage present?
Bright red patch of blood
What is glaucoma?
optic nerve damage caused by a rise in intra-ocular pressure
What is a normal intra-ocular pressure?
10-21 mmHg
At which intraoccqular pressure is treatment for glaucoma started?
24mmHg
What is considered to be an abnormal cup:disc ratio?
> 0.5 is abnormal
What is the gold standard test for diagnosing glaucoma?
Goldmann applanation tonometry