Central Retinal Artery Occlusion

Question 1

What is central retinal artery occlusion?

Answer 1

A blockage of blood flow in the central retinal artery which is a branch of the opthalmic/internal cartoid

Question 2

What causes CRAO?

Answer 2

• Most common cause of atherosclerosis
• GCA can also cause it where vasculitis of these vessels reduces blood flow

Question 3

What are risk factors for CRAO?

Answer 3

• Older age
• FH
• Smoking/Alcohol
• Diabetes
• Poor diet/Obesity

Question 4

How does CRAO present?

Answer 4

• Sudden painless loss of vision
• Relative afferent pupillary defect: Pupil in affected eye constricts more when light is shone in other eye compared to affected eye

Question 5

How is CRAO investigated?

Answer 5

• Fundoscopy which shows pale retina (due to lack of perfusion) and cherry red spot (macula)

Question 6

How is CRAO managed?

Answer 6

• Immediate referral to ophthalmologist
• GCA is an important reversible cause
• Ocular massage can be used
• Inhaling carbogen (to dilate artery)
• Sublingual isosorbide dinitrate
• Long term management is treat reversible risk factors and secondary prevention