central retinal artery occlusion

Question 1

cause of central retinal artery occlusion

Answer 1

thromboembolism from atherosclerosis
cardiac emboli
local atheromaa in central retinal artery
arteritis - GCA
hypercoaguable state - sickle cell disease, antiphospholipid
infection
COCP
cocaine
raised IOP
trauma
vasospasm/migraine

Question 2

features of CRAO

Answer 2

sudden, painless unilateral visual loss
reduced visual acuity
relative afferent pupillary defect
‘cherry red’ spot on a pale retina
can be preceded by amaurosis fugax
perform systemic ex to look for causes

Question 3

ix for central retinal artery occlusion

Answer 3

flurescein stain if fundoscopy unclear - absent filling of retinal artery with fluorescein angiography
aimed at finding cause
* CRP / ESR
* carotid artery duplex / US doppler
* echo
* blood tests

Question 4

mx of central retinal artery occlusion

Answer 4

1. treated with 6hr of visual loss onset - reperfusion

• intra-arterial thrombolysis with urokinase
• ocular massage - if within 90mins - dislodge obstruction
• reduction of IOP - anterior chamber paracentesis + acetazolamide
• vasodilatory therapy - sublingual isosorbide dinitrate

2. rx of underlying condition

Question 5

secondary prevention of CRAO

Answer 5

due to risk of MI and stroke
depending on cause - eg
* carotid endarterectomy
* anticoag
* anti-plt and atherosclerosis RF modification

refer to opthal - long term follow up

Question 6

px of CRAO

Answer 6

70% have visual loss even with rx