Retinal Vessel Occlusion

Question 1

What is the pathophysiology of retinal vein occlusion?

Answer 1

Thrombus forms in veins and blocks blood drainage from retina, causes blood pooling, leakage of fluid, macular oedema. Also causes tissue damage in retinal and vision loss, release of VEGF (neovascularisation).

Question 2

What structure does the central retinal vein run through?

Answer 2

Optic nerve

Question 3

What is this a presentation of:

Sudden painless loss of vision, RAPD, flame and blot haemorrhages, optic disc oedema, macular oedema?

Answer 3

Retinal vein occlusion

Question 4

What are the risk factors for retinal vein occlusion?

Answer 4

Hypertension, high cholesterol, diabetes, smoking, glaucoma, systemic inflammatory conditions.

Question 5

What additional investigations are done in retinal vein occlusion to rule out associated conditions?

Answer 5

1. FBC - anaemia
2. ESR - inflammatory disorders
3. Blood pressure - hypertension
4. Serum glucose - diabetes

Question 6

What is the treatment for retinal vein occlusion?

Answer 6

Refer to ophthalmology, laser photocoagulation, intravitreal steroids, anti-VEGF therapies.

Question 7

What is the pathophysiology of retinal artery occlusion?

Answer 7

Blood flow through central retinal artery blocked (branch of ophthalmic artery).

Question 8

What are the two common causes of retinal artery occlusion?

Answer 8

Atherosclerosis and giant cell arteritis (vasculitis).

Question 9

What are the risk factors for retinal artery occlusion?

Answer 9

Elderly, family history, smoking, alcohol, hypertension, diabetes, poor diet, inactivity, obesity.

Question 10

What is this a presentation of:

Sudden painless loss of vision, RAPD, pale retina with cherry-red spot?

Answer 10

Retinal artery occlusion

Question 11

What causes the pale retina and the cherry red spot in retinal artery occlusion?

Answer 11

1. Pale retina - lack of perfusion

2. Cherry red spot - thin macula showing red choroid below

Question 12

What is the treatment for retinal artery occlusion?

Answer 12

Refer to ophthalmology, treat giant cell arteritis, high dose steroids (prednisolone 60mg).

Question 13

How is giant cell arteritis in retinal artery occlusion diagnosed?

Answer 13

ESR and temporal artery biopsy.

Question 14

What are the method for dislodging a thrombus in retinal artery occlusion?

Answer 14

1. Ocular massage
2. Removing fluid from anterior chamber to reduce intraocular pressure.
3. Inhaling carbogen (5% carbon dioxide, 95% oxygen) to dilate artery.
4. Sublingual isosorbide dinitrate to dilate artery.

Question 15

What is the long-term management of retinal artery occlusion?

Answer 15

Treat reversible risk factors and secondary prevention of CVD.