Glaucoma

Question 1

Define glaucoma…

Answer 1

Characterised by optic disc cupping and visual field loss, where IOP can be raised to impair normal optic nerve function.

Question 2

What is (Primary) Open Angle Glaucoma?

Answer 2

1) Raised IOP > 21mmHg
2) OPEN aqueous drainage angle
3) Pathologically cupped optic disc
4) Glaucomatous visual field loss

Question 3

What is occular hypertension?

Answer 3

Raised IOP > 21mmHG BUT normal optic disc and field. The condition is asymptomatic.

Question 4

What is the cup-to-disc ratio (CDR)?

Answer 4

Compares the cup portion of the optic disc with the total diameter of the optic disc.
Normal CDR is <0.3.
Large CDR may imply glaucoma or other pathology.

Question 5

The stages of glaucomatous visual field loss are…

Answer 5

1) Initially nasal step
2) Superior and inferior arcuate scotomas
3) Temporal and central islands
4) Complete field loss

Question 6

Perimetry can be measured by using…

Answer 6

1) Goldmann fields –> kinetic

2) Humphrey fields –> static

Question 7

What topical medications treat glaucoma?

Answer 7

1) Prostaglandin F2 alpha analogues –> Increase uveo-scleral outflow
2) Beta blockers –> Decrease aqueous production
3) Carbonic anhydrase inhibitors –> Decrease aqueous production
4) Alpha-2 agonists –> BOTH

Question 8

What systemic treatments treat glaucoma?

Answer 8

1) Carbonic anhydrase inhibitor (EG: acetazolamide) –> Given by IV for close angle glaucoma

Question 9

What are the surgical options for glaucoma?

Answer 9

1) Trabeculectomy –> forms fistula between anterior chamber and sub-conjuctival space
2) Augmentation –> topical chemotherapy
3) Laser to trabecular meshwork

Question 10

What are the different types of glaucoma?

Answer 10

1) Open angle glaucoma
2) Closed angle glaucoma
3) Normal (low) tension glaucoma