retinal vascular occlusion
TRANSCRIPT
RETINAL VASCULAR OCCLUSIONS
Retinal vein occlusion• Branch• Central• Hemi-retinal
Retinal artery occlusion• Branch• Cilio-retinal• Hemi-retinal• Central
Retinal vein occlusion - predisposing factors
1. Systemic
• Raised intraocular pressure2. Ocular
• Periphlebitis
• Increasing age• Hypertension• Diabetes• Abnormalities of coagulation
Patho-physiology of venous occlusion
Venous Occlusion
Stagnation
Increased extravascularpressure
Hypoxia
Oedema andhaemorrhage
Branch retinal vein occlusion ( BRVO )
• Venous tortuosity and dilatation• Flame-shaped and ‘dot-blot’ haemorrhages• Cotton-wool spots and retinal oedema
Prognosis - VA 6/12 or better after 6 months in 50%
Complications - chronic macular oedema and neovascularization
Signs of acute BRVO
FA of branch retinal vein occlusion
Early - blocked background fluorescence due to haemorrhage
Late - hyperfluorescence dueto diffuse oedema
Signs of old branch retinal vein occlusion
Vascular sheathing and collaterals Hard exudates
Management of chronic macular oedema• Most common cause of persistent poor VA• Wait 6-12 weeks and perform FA
Macular non-perfusion - no treatment Good macular perfusion and VA 6/18or worse after 3 months - consider laser photocoagulation
Management of neovascularization
• Perform laser photocoagulation to involved segment• Most frequently after 6-12 months
• Occurs in about 30-50% of eyes
Central retinal vein occlusion ( CRVO )
• Chronic macular oedema
• Variable cotton-wool spots
• Mild to moderate disc oedema
• May subsequently convert to ischaemic
• Guarded prognosis
• VA > CF• APD - mild• Mild venous tortuosity and dilatation• Mild to moderate retinal haemorrhages
Signs of non-ischaemic CRVO
FA of non-ischaemic central retinal vein occlusion
Good retinal capillary perfusion
Signs of ischaemic central retinal vein occlusion
• Variable cotton wool spots• Severe disc oedema
• Very poor prognosis
• Macular ischaemia
• Rubeosis irides in 50%
• VA < 6/60• APD - marked• Marked venous tortuosity and engorgement• Extensive retinal haemorrhages
FA of ischaemic central retinal vein occlusion
Extensive capillary non-perfusion
Management of ischaemic central retinal vein occlusion
• Check every month for 6 months• Look for rubeosis and angle new vessels
• Treat neovascularization by panretinal photocoagulation
Hemi-retinal Vein Occlusion• VA< reduction is variable• Signs of BRVO• Superior or inferior hemisphere
involve
FA Hemi-retinal Vein Occlusion
Management of CRVO• Radial Optic Neurotomy
• A-V sheathotomy
• Chorio-retinal anastomosis
• Laser
• Surgical
• IVTA
• Anti-VEGF
RETINAL ARTERY OCCLUSION
Causes of retinal artery occlusion
Embolism
Vaso-obliteration
Cholesterol emboli (Hollenhorst plaques)
• Multiple, bright, refractile crystals• Often located at arteriolar bifurcations• Frequently asymptomatic
Fibrinoplatelet emboli
• Multiple, dull grey particles• Occasionally fill entire lumen• May cause amaurosis fugax and occasionally permanent obstruction
Calcific emboli
• Usually single, white and close to disc• May cause permanent obstruction
Branch retinal artery occlusion ( BRAO )
• VA - variable
• APD - mild or absent
• Retina whitening
• Arteriolar narrowing
FA of branch retinal artery occlusion
Early masking Extreme delay of arterial phase
Late staining of arterial walls
Cilioretinal artery occlusion
• Present in about 30% of individuals
• In young individuals with a systemic vasculitis
• Guarded prognosis
Combined with CRVO
• Usually good prognosis
• Elderly patients with giant cell arteritis
• Very poor prognosis
IsolatedCombined with anterior ischaemic optic neuropathy
• Cilioretinal artery derived from posterior ciliary circulation
Central retinal artery occlusion ( CRAO )
• VA < 6/60
• ‘Cherry-red spot’ at macula
• Arteriolar and venular narrowing
• Very poor prognosis
• Sludging and segmentation of blood column (cattle-trucking)
• APD - marked
• Retinal whitening
FA of central retinal artery occlusion
Early filling of cilioretinal artery
Non-filling of other vessels Late staining of vessel walls
Treatment of central retinal artery occlusion
• Ocular massage• Sub-lingual Iso-sorbide di-nitrate• Lowering of IOP
• AC paracentesis• IV Streptokinase