Aqueous humour production and circulation and glaucoma

Question 1

Where is aqueous humour produced?

Answer 1

The epithelial layer of the ciliary body

Question 2

Where does the aqueous humour flow in the eye?

Answer 2

Produced into the posterior chamber

Flows into the anterior chamber

Drains into the scleral venous sinus, through a trabecular meshwork and the canal of Schlemm

This is situated in the angle iris and cornea: idiocorneal angle

Question 3

What is glaucoma?

Answer 3

Raised intra-ocular pressure caused by an imbalance between rates of secretion and removal of aqueous humour

Question 4

What drugs can be used to treat glaucoma?

Answer 4

Carbonic anhydrase inhibitors:

Dorzolamide (eye drops)

Acetazolomide (oral tablets, can cause kidney problems)

Question 5

Which is the most common kind of glaucoma?

Answer 5

Open angle glaucoma

Question 6

How does an open angle glaucoma present?

Answer 6

Late - usually painless and asymptomatic

Question 7

How does a closed angle glaucoma present?

Answer 7

Acutely - sudden pain, redness, nausea and vomiting

Question 8

What is the pathology in open angle glaucoma?

Answer 8

Dysfunction of the trabecular meshwork, reducing flow

Question 9

What is the pathology in closed angle glaucoma?

Answer 9

The iridocorneal angle is completely closed by forward displacement of the root of the iris against the cornea

Question 10

What sign on opthalmoscopy can indicate glaucoma?

Answer 10

Increased cup-to-disc ratio
Pale disc