Pupils

Question 1

RAPD (Marcus-Gunn pupil)

a) Explain
b) Causes

Answer 1

a) Dysfunction of afferent limb in optic pathway, where pupils respond differently to light stimuli shone in one eye at a time. When affected eye shone into, both eyes dilate/fail to constrict
- swinging light test

b) - Retinal: damage
- Optic nerve: neuritis, compression, ischaemia

Question 2

Sudden eye pain, redness, vision loss, nausea and vomiting. Mid-dilated pupil.

• Cause?
• Pressures
• Management

Answer 2

• acute angle-closure glaucoma
• normal IOP = 12 - 22, pathological > 22
• topical cholinergics (pilocarpine), beta-blocker (e.g. timolol) and steroids + IV acetazolamide

Question 3

Antimuscarinics.

a) Mydriasis vs. cycloplegia
b) Short-acting
c) Longer-acting

Answer 3

a) Mydriasis - dilates pupil
Cycloplegia - paralyses ciliary muscle
(Antimuscarinics do both of these things)

b) Tropicamide (4-6h) - allows examination of fundus
c) Cyclopentolate (24h), atropine (7 days)

Question 4

Holmes-Adie pupil.

a) Define
b) What is Holmes-Adie syndrome?
c) How to confirm the diagnosis?

Answer 4

a) Dilated pupil (unilateral), delayed and poor constriction to light
b) Holmes-Adie pupils + reduced deep tendon reflexes (common in young women)

c) Low-dose topical pilocarpine (parasympathomimetic):
- Normal pupils will not constrict due to low dose
- Adie pupils will constrict

Question 5

Argyll-Robertson pupil.

a) Define
b) Classic cause
c) If coupled with a vertical gaze palsy - cause?

Answer 5

a) Constricted pupil, poor constriction to light BUT good constriction on accommodation
(accommodates but doesn’t react)

b) Neurosyphilis (prostitute’s pupil)
c) Parinaud syndrome - secondary to pineal gland tumour, MS or stroke