Glossary of Glaucoma treatment

Start Studying! Add Cards ↓

What are the types of glaucoma?
Open angle--most common
Narrow angle
What is open angle glaucoma (OAG)?
Histological change in trabecular meshwork that slows outflow of aqueous humor --> increases amount of aqueous humor in eye --> increases introcular pressure
What can be done to treat OAG?
Decrease aqueous humor production (turn off tap) and increase aqueous humor outflow (unclog the drain)
What non-selective beta blockers are used for OAG?
What beta 1 selective blockers used for OAG?
What is the MOA of beta blockers in OAG?
Beta blockers --> decrease aqueous humor production by the ciliary body --> decreases IOP (20-30%)
What direct acting adrenomimetics are used for OAG?
Epinephrine--A and B
Dipivefrin --A and B
How does Brimonidine work on OAG?
A2 on ciliary epithelium --> decrease aqueous humor production --> decrease intraocular pressure (IOP)
How does EPI work on OAG?
EPI --> B2 on endothelial cells of trabecular meshwork --> increases outflow of aqueous humor --> decrease IOP
What cholinomimetics used for glaucoma?
Muscarinic agonists--Pilocarpine and Carbachol
Reversible AChE inhibitors--Physostigmine
Irreversible AChE inhibitors--Echothiophate
How does a cholinomimetic work on OAG?
Pilocarpine --> contracts ciliary muscle --> pulls on trabecular meshwork --> opens "holes" --> increases ouflow of aqueous humor
Treatment of OAG with Epinephrine...
Increases outflow and decreases production --> no blurred vision
Less effective
Treatment of OAG with Brimonidine and Betaxolol...
Decreased production --> no blurred vision
Treatment of OAG with Pilocarpine...
Increased outflow --> blurred vision (affects ciliary muscle)
Why do you get blurred vision with Pilocarpine and not betaxolol?
Pilocarpine activates M receptors on the ciliary muscle
What is the first choice treatment in OAG?
Beta blockers
What are the alternative tx choices for OAG?
Pilocarpine (first)
Echothiophate (last)
What is the advantage of using a beta blocker (betaxolol) over pilocarpine for treating OAG?
Less side effects and no effect on the lens (doesnt move ciliary muscle)
What topical carbonic anhyddrase inhibitors are used for OAG?
What prostaglandins are used in OAG?
How does marijuana affect glaucoma?
Lowers IOP by about 24%
Does not work topically
MOA unknown
Cannabinoid receptors found--retina, ciliary body, and iris
What is the potential problem with marijuana and glaucoma?
DOA only 3-3.5 hours and the goal is to maintain a continuous lowering of IOP
dont know if interferes with other glaucoma meds
What is narrow angle glaucoma (NAG)?
There is a structural defect in the eye that causes a narrow angle between the iris and the cornea.
When do attacks of NAG occur?
When the pupil is dilated --> obstructs the outflow of aqueous humor through the trabecular meshwork
What would happen if outflow through the trabecular is blocked?
Attack of NAG --> IOP can increase from 15 mmHG to 40-60 mm Hg --> can cause blindness
How does Pilocarpine treat NAG?
Pilocarpine --> contract the iris sphincter smooth muscle --> induce miosis --> pulls the iris away from the trabecular meshwork --> increase outflow of aqueous humor --> decrease IOP
Will pilocarpine be used chronically for the treatment of NAG?
No, it is used to reduce pressure during an acute attack. Chronic treatment or cure is iridectomy.
What are the alternative tx for NAG attaks?
Decreasing aqueous humor production with other drugs (beta blockers) may be helpful but takes too long
How does cholinomimetics work on NAG?
Pilocarpine --> NAG --> contract iris sphincter muscle --> move iris out of the way --> increase outflow

Add Cards

You must Login or Register to add cards