Central Retinal Artery Occlusion

Question 1

What is central retinal artery occlusion?

Answer 1

It is defined as a condition in which there is sudden occlusion of the artery supplying the inner retina

Question 2

What is the central retinal artery a branch of?

Answer 2

Opthalmic artery

Question 3

What is the opthalmic artery a branch of?

Answer 3

Internal carotid artery

Question 4

What are the two causes of central retinal artery occlusion?

Answer 4

Thromboembolism

Giant Cell Arteritis

Question 5

What is the most common cause of central retinal artery occlusion?

Answer 5

Thromboembolism in the internal carotid artery

Question 6

What are the ten risk factors of central retinal artery occlusion?

Answer 6

Older Age

Family History

Hypertension

Diabetes Mellitus

Hyperlipidaemia

Carotid Artery Stenosis

Atrial Fibrillation

Obesity

Smoking

Alcoholism

Question 7

What are the four clinical features of central retinal artery occlusion?

Answer 7

Sudden Painless Unilateral Vision Loss

Reduced Unilateral Visual Acuity

Relative Afferent Pupillary Defect (RAPD)

Pale Retina With Central Cherry-Red Spot

Question 8

What is RAPD?

Answer 8

It is when the pupil in the affected eye constricts more when the light is shone in the other eye, compared to when it is shone in the affected eye

Question 9

How is RAPD associated with central retinal artery occlusion?

Answer 9

This occurs because the input is not being sensed by the ischaemic retina when testing the direct light reflex

However it is being sensed by the normal retina during the consensual light reflex

Question 10

How is a pale retina associated with central retinal artery occlusion?

Answer 10

There is hypoperfusion of the retina

Question 11

What are the two investigations used to diagnose central retinal artery occlusion?

Answer 11

Blood Tests

Temporal Artery Biopsy

Question 12

What are the five blood test results indicative of central retinal artery occlusion?

Answer 12

Increased ESR Levels

Increased CRP Levels

Increased LDH Levels

Increased HbA1C Levels

Vasculitic Screening

Question 13

What do increased ESR/CRP levels indicate in central retinal artery occlusion?

Answer 13

That the underlying cause could be giant cell arteritis

Question 14

What do increased LDH/HbA1C levels indicate in central retinal artery occlusion?

Answer 14

That the underlying cause could be thromboembolism

Question 15

Which are the four antibodies screened for in vasculitis?

Answer 15

ANA

ENA

ANCA

AEC

Question 16

Why is a vasculitic screen used to diagnose central retinal artery occlusion?

Answer 16

It is used to identify giant cell arteritis

Question 17

How is a temporal artery biopsy used to investigate central retinal artery occlusion?

Answer 17

It is used to identify giant cell arteritis

Question 18

What is the most appropriate management step in suspected central retinal artery occlusion?

Answer 18

Urgent opthalmology referral

Question 19

What is the aim of central retinal artery occlusion immediate management options?

Answer 19

They aim to dislodge the thrombus from the artery

Question 20

What are the five immediate management options of central retinal artery occlusion?

Answer 20

Ocular Massage

Anterior Chamber Paracentesis

IV Acetazolamide & Mannitol

Sublingual Isosorbide Dinitrate

Carbogen Inhalation

Question 21

How is anterior chamber paracentesis used to manage central retinal artery occlusion?

Answer 21

It is used to reduce intraocular pressure

Question 22

How is IV acetazolamide and IV mannitol used to manage central retinal artery occlusion?

Answer 22

It is used to reduce intraocular pressure

Question 23

How is carbogen inhalation used to manage central retinal artery occlusion?

Answer 23

It is used to dialte the retinal artery

Question 24

How is sublingual isosorbude dinitrate used to manage central retinal artery occlusion?

Answer 24

It is used to dilate the retinal artery

Question 25

How do we manage patients who present acutely within 24 hours of onset?

Answer 25

Intra-arterial fibrinolysis

OR

Intravenous thrombolysis

Question 26

How do we conduct intra-arterial fibrinolysis in order to manage central retinal artery occlusion?

Answer 26

We locally inject urokinase into the proximal part of the ophthalmic artery

Question 27

How do we conduct intravenous thrombolysis in order to manage central retinal artery occlusion?

Answer 27

We administer an IV tissue plasminogen activator (tPA), such as altepase

Question 28

How do we manage central artery occlusion related to giant cell arteritis?

Answer 28

IV corticosteroids

Question 29

What are the six long term management options of central retinal artery occlusion?

Answer 29

Low Glycaemic Index Diet

High Vitamin B6 & B12 Diet

Regular Exercise

Smoking Cessation

Atherosclerotic Disease Optimisation

DVLA Notification If Complete Unilateral Vision Loss

Question 30

What is a complication of central retinal artery occlusion?

Answer 30

Neovascularisation

Question 31

When does neovascualrisation in central retinal artery occlusion occur?

Answer 31

> 8 weeks

Question 32

What are the two clinical features of neovascularisation?

Answer 32

Vitreous haemorrhage

Glaucoma

Question 33

How do we manage neovascularisation in central retinal artery occlusion?

Answer 33

Pan-retinal photocoagulation