Ophthalmology Flashcards
Adragenrgic receptors of the Iris sphincter
cholinergic?
equal alpha and beta
muscarinic
Ciliary muscle:
adrenergic receptors
cholinergic receptors
some beta 1, few alpha
MUSCARINIC
Iris dilator
adrenergic receptors
cholinergic receptors
mostly alpha 1, few beta
no cholinergics
ciliary processes
adrangergics
cholinergics
mostly beta2, some alpha2, few beta1
muscarinic
mueller muscle
adrangergics
cholinergics
alpha 1
no cholinergics
used for mydriasis
diagnostic for dilated fundus exam
phenylephrine
primary therapeutic intervention of glaucoma until about 1978
what is the treatment now?
epinephrine
timolol (beta blocker)
why isn’t epinephrine effective to stimulate mydriasis?
what is the MOA of epinephrine in glaucoma
- melanin of the iris binds and inhibits it
- alpha and beta stimulation in ciliary processes, increases aqueous product
- beta2 stimulation relaxes the trabecular meshwork
Epinephrine side effect in the eye
burning, irritation, rebound injection
pupil dilation and lid retraction (mueller’s muscle) via alpha 1 receptors
pigmentation of iris and lens (oxidized epinephrine deposits)
angle closure
increase IOP
cystoid macular edema: swelling of center portion of retina
direct alpha 1 agonist
synthetic sympathomimetic of epinephrine
used for pupil dilations
used for decongestion
phenylephrine
used to break posterior synechia to the lens due to uveitis
10% phenylephrine
does phenylephrine cause cycloplegia?
does the light reflex remain intact?
no
yes, need to add an anticholinergic to maintain dilation for eye exams and surgery
direct alpha agonist, some selectivity for alpha 2
derivative of clonidine
activated alpha 2 receptors on the presynaptic adraergic terminals to the ciliary processes, reducing NE release and decreasing aqueous product
apraclonidine
star wars clone wearing an apron, treats the eye after a laser attack
what are the MOAs of apraclonidine on the:
- ciliary process epithelium
- episcleral venous pressure
- reduces cAMP, decreasing aqueous product
- decreases pressure in the ciliary processes allows more drainage into the uveoscleral venous system
apraclonidine use for pre and post op glaucoma sx
prevents IOP spike from inflammation
usually first line for normal tension glaucoma
highly selective for alpha 2 receptors
brimonidine
bro money thinks he’s the alpha dog (hence the alpha 2)
differentiaties pre or post ganglionic horner’s syndrome
hydroxyamphetamine
preganglionic horners, give pt hydroxyamphetamine
pupil dilates
postganglionic horners, give pt hydrocyamphetamine
no pupil dilation
alpha blocker aka Rev eyes
reverses mydriasis caused by phenylephrine
causes hyperemia and mild ptosis (name the organs affected)
dapiprazole
da paper sole, blocks alpha receptors
conjunctival vessels and mueller’s mm have been antagonized
nonselective beta blocker, prototype
no sympathomimetic activity
blocks beta receptors at the ciliary processes which reduces aqueous production
timolol
the time mole hates beta fish, replaced epinephrine as the gold standard for glaucoma tx
MOA of levubunolol and metipranolol
nonselective beta blockers
levitating buns and mets pro are there to back the time mole up in his hatred of beta fish
which drug class causes bradycardia, respiratory distress, and exacerbates myasthenia graves? what diseases are contraindicated
nonselective beta blockers
CHF and COPD
selective beta1 blocker
good for COPD and asthma
betaxolol
betty the taxer, selects for 1 tax form at a time, lets the 2 lungs breathe though
used to break angle closure glaucoma until laser iridotomy can be performed
direct cholinergic agonist
pilocarpine (topical)
pile of cars, releases IOP by opening the trabecular meshwork
ocular side effects of pilocarpine
accommodative spasm
miosis
long lasting mitosis
used in complicated cataracts surgery to maintain lens in posterior chamber
carbachol
the car bagel, keeps the windshield in the right place
reversible antiacetylcholinesterases
physostigmine and neostigmine
the fist stigma and neo stigma from the matrix, punch acetylcholinesterase in the face
irreversible acetylcholinesterase inhibitors
cause really bad side effects: iris cysts, GI symptoms, and accelerated cataracts
ecothiophate and isoflurophate
uncle wearing EKKO ultd. with a mask of isoflo before surgery. he’s laying on the ach esterase table, and won’t be getting up anytime soon
how to cholinergic antagonists (antimuscarinics) work to promote:
mydriasis
cycloplegia
pain relief in uveitis
- inhibit iris sphincter mm
- inhibit ciliary mm
- inhibition of iris and ciliary mm relieves pain, reducing risk of posterior synechia
antimuscarinic used for mydriasis
used with phenylephrine in standard DFE
no good for cycloplegia
tropicamide
the tropicana lady is so hot that your pupils dilate to take her in
antimuscarinic used for mydriasis
used in ocular sx
not used for standard DFE because it lasts 24 hours
good for cycloplegia
cyclopentolate
cyclops with a really dilated pupil, is pissed because he can’t see anything for about a day. he’s also paralyzed btw
antimuscarinic used for mydriasis and cycloplegia up to 48 hours
used in inflammatory conditions
relieves pain by reducing the amount of inflammatory markers that get forced out during contraction
homatropine
homatrope kind of sounds like cannabalism. this guy likes to abduct people for 2 days at a time
antimuscarinic with extreme mydriasis and cycloplegia, lasts 7-12 days
used in infants and children under 5 years for DFE
never used in down syndrome
atropine
a trooper that catches children, works for weeks at a time without taking a break. must be a lot of kids to catch out there.
which antimuscarinic is safe for glaucoma pts?
tropicamide
what do you give a patient with a unilateral dilated pupil?
no history of trauma
give pilocarpine, if dilates than its Adie’s tonic pupil
if no dilation, increase the dose
if it dilates, they need imagine
if no dilation then its pharmacologic
