Aqueous Humor Pathway

Question 1

Where is aqueous humor produced?

Answer 1

Aqueous humor is produced in the non-pigmented epithelium on the ciliary body.

Question 2

What drugs can be used to decrease aqueous humor production?

Answer 2

1. Beta blockers
2. alpha 2 agonists
3. Carbonic Anhydrase inhibitors

Question 3

Describe the flow of aqueous humor out of the eye.

Answer 3

After aqueous humor is produced in the ciliary body, it passes anterior to the lens between the iris. It then flows over the anterior portion of the iris and through either the trabecular outflow (90%) tract or uveoscleral outflow (10%).

Question 4

What is the trabecular outflow tract?

Answer 4

Drainage occurs through the canal of Schlemm and then the episcleral vasculature absorbs the aqueous humor.

Question 5

What drugs can increase aqueous humor outflow through the trabecular outflow tract?

Answer 5

Muscarinic agoninst (M1) increase outflow through the trabecular outflow tract.

Question 6

What is the uveoscleral outflow tract?

Answer 6

Drainage of aqueous humor occurs into the uvea and sclera.

Question 7

What drugs increase aqueous humor drainage out of the uveoscleral outflow tract?

Answer 7

Prostaglandin agonists increase flow of aqueous humor out of the uveoscleral outflow tract.