Ophthalmology

Question 1

How does acute angle closure glaucoma present? (Symptoms)

Answer 1

Decreased vision and aching pain in eye (usu. unilateral) which can progress to a frontal headache with assoc. N and V

Question 2

What eye signs are seen in an acute angle closure glaucoma?

Answer 2

Mid-dilated (oval) sluggish pupil and hazy cornea due to oedema

Question 3

How is an acute angle closure glaucoma managed in the acute setting?(4)

Answer 3

1. Keep head up - at least 30 degrees
2. Topical treatment: pilocarpine (cholinergics) or acetazolamide (carbonic anhydrase inhibitor) or topical b blocker (timolol)
3. Symptomatic relief of pain and N and V
4. Urgent Ophthalmology referral because severe and permanent damage may occur within hours

Question 4

List two primary causes of acute angle closure glaucoma

Answer 4

1. Pupillary block: posterior iris contacts lens

2. Angle crowding: due to abnormally configured iris

Question 5

List some secondary causes of acute closure angle glaucoma

Answer 5

1. Neovascular glaucoma e.g. DM

2. Drugs that cause ciliary body swelling e.g. Topiramate and sulfonamide

Question 6

What is the pathophysiology behind acute angle closure glaucoma?

Answer 6

Problems with trabecular drainage - outflow of aqueous humour blocked causing increased intra ocular pressure

Question 7

Which is worse - acid or alkali eye injuries? Why?

Answer 7

Alkalis are worse. Involves liquefactive necrosis - no precipitation of proteins and substance rapidly penetrates deeper layers

Acid injuries involves coagulative necrosis which means damaged tissue forms a barrier to deeper injury

Question 8

List some examples of things that cause acid eye injuries

Answer 8

Toilet cleaner
Pool cleaner
Battery fluid

Question 9

List some examples of things that cause alkali eye injuries

Answer 9

Lime (found in cement)
Plaster
Drain cleaner

Question 10

How are acidic and alkaline eye injuries managed? (5)

Answer 10

Irrigation using a Morgan lens

1. Anaesthetise eye with local
2. Slide Morgan lens under eyelid onto eye - attached to saline - irrigate for 30 mins
   3 test pH - remove lens and wait 5 mins, place indicator paper under eyelid. Can stop if pH is between 6.5 - 8.5, if not should continue
3. Assessment - what chemical? How much? Ring poisons centre
4. Ophthalmology consult