Occlusion

Question 1

Risk factors for retinal vein occlusion

Answer 1

-Age
-Hypertension
-Smoking
-Hyperlipidaemia
-Polycythaemia
-Diabetes
=Atherosclerosis

-Glaucoma
-COCP
-myeloma
=Venule compression at arterial crossing

Question 2

Risk factors for retinal artery occlusion

Answer 2

-Atherosclerosis
-Carotid disease
-GCA
=Thrombosis and embolism from carotids

Question 3

Symptoms of vessel occlusion

Answer 3

-Sudden painless unilateral vision loss
-RAPD

Question 4

Signs of RVO

Answer 4

-Central= stormy sky/ blood and thunder/ pan pizza, flame shaped haemorrhages, tortuous vessels, swollen disc
-Branch= retinal haemorrhages, venous tortuosity/ dilation, no disc involvement?

Question 5

Signs of RAO

Answer 5

-Central= cherry red spot (underlying choroidal circulation), pale retina. Sudden painless vision loss, RAPD
*20% population have cilioretinal artery from posterior ciliary circulation and supplies part of macula
-Branch
=Pale retina, emboli, optic atrophy. Sectoral/ altitudinal visual field loss (sudden painless).

Question 6

Investigations for RVO

Answer 6

-BP, FBC, ESR, U&Es, Glu, lipids, protein electrophoresis, TFT, ECG
-Fluorescein Angiography!
-Optical Coherence Tomography

Question 7

Investigations for RAO

Answer 7

-PTT, APTT, thrombophilia screen, vasculitis autoantibodies, ECG,ECHO, carotid Doppler scans

Question 8

Management of RAO

Answer 8

IV acetazolamide, ocular massage, protect other eye (treat GCA!), supine posture, anterior chamber paracentesis
NOT USEFUL

=TIA clinic referral
=Cannot drive 1 month if other eye good

Question 9

Complications of RVO and their management

Answer 9

-Macular oedema (intravitreal steroid and anti VEGF) NON ISCHAEMIC and ISCHAEMIC
-Neovascularisation (pan-retinal photocoagulation) ISCHAEMIC
-Rubeosis iridis (neovascularisation of iris, can lead to rubeotic glaucoma as climb onto trabecular meshwork).

Question 10

Non-ischaemic CRVO vs ischaemic CRVO

Answer 10

-NICRVO: 75%, VA> 6/60, slight/ no RAPD, no visual field defect, less haemorrhage and cotton wool spots, good perfusion FFA, better prognosis

-ICRVO: 25%, VA <6/60, marked RAPD, common visual field defect, extensive haemorrhage and cotton wool spots, non perfusion, rubeosis

Question 11

Describe hemiretinal vein occlusion

Answer 11

-Presentation: altitudinal visual loss, involves superior or inferior hemisphere (affects opposite field)
-Treatment: extensive retinal ischaemia= ischaemic CRVO treatment/ otherwise non-ischaemic treatment

Question 12

Describe branch retinal vein occlusion

Answer 12

-Usually superior temporal

-Macular sparing= observe
-Macular oedema/ involvement= sector laser photocoagulation (ischaemia), intravitreal anti-VEGF