FN: Glaucoma (chronic open angle)

Question 1

Pathogenesis

Answer 1

• Depends on susceptibility of patients retina and optic nerve to raised IOP damage
• IOP >21mmHg leads to reduced blood flow and damages to optic nerve - optic disc atrophy (pale) and cupping

Question 2

Presentation

Answer 2

Perpheral visual field defect: superior nasal first
Central field is intact therefore acuity maintained until late - presentation delayed until optic nerve damage is irreversible

Question 3

Screening

Answer 3

If risk is high

• > 35yrs
• Afro-Caribeen
• FH
• Drugs: steroids
• Co-morbidities: DM, HTN, migraines
• Myopia

Question 4

Investigations

Answer 4

1. Tonometry: IOP >21 mmHg
2. Fundoscopy: cupping of optic disc
3. Visual field assessment: peripheral loss

Question 5

Management

Answer 5

Life long followup

Question 6

Medical Mx

Answer 6

Eye-drops to reduced IOP to baseline
1st line: Betablockers
Prostaglandin analogues
alpha-agonists
Carbonic anhydrase inhibitors
Miotics

Question 7

Betablock action and drug names

Answer 7

Timolol, betaxolol
Reduce aqueous production
Caution in asthma, heart failure

Question 8

Prostaglandin analogues action and drug names

Answer 8

Latanoprost, travoprost

Raise uveoscleral outflow

Question 9

Alpha agonist action and drug names

Answer 9

Brimonidine, apraclonidine

Reduce aqeous production and raised uveoscleral outflow

Question 10

Carbonic anyhdrase inhibitors name and action

Answer 10

Dorzolamide drops, acetazolamide PO

Question 11

Miotics name

Answer 11

Pilocarpine

Question 12

Non-medical options

Answer 12

Laser trabeculoplasty

Surgery (trabeculectomy) if used if drugs fail - new channel allows aqueous to flow into conjuntival bleb