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Arterial and Venous Occlusive Disease of the Retina. Dr.M NAQEEB Assistant professor Um Al-Qura university . Objective . Central retinal artery occlusion Branch retinal artery occlusion Branch retinal vein occlusion Central retinal vein occlusion.
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Arterial and Venous Occlusive Disease of the Retina Dr.M NAQEEB Assistant professor Um Al-Qura university
Objective • Central retinal artery occlusion • Branch retinal artery occlusion • Branch retinal vein occlusion • Central retinal vein occlusion
retinal artery obstructions • 57% of obstructions involved the central retinal artery • 38% involved one of the branch retinal arteries • 5% involved the cilioretinal artery
Central Artery Obstruction • Characteristics • Sudden severe visual loss • Painless • Retinal appearance • Opaque and edematous • Most prominent in posterior pole • Thickest ganglion cell layer • Cherry-red spot • Visible intact choroidal vasculature beneath the foveola
Central Artery Obstruction • Characteristics • With time • Artery re-canalizes • Edema clears • Visual loss is devastating and permanent • Irreversible damage to neural tissue after 90 minutes
Central Artery Obstruction • Prognosis • 20/400 or worse: 2/3 of eyes • 20/40 or better: 1/6 eyes • Intact cilioretinal artery • Vision of NLP • Implies ophthalmic artery occlusion • Choroidal ischemia as well
Central Artery Obstruction • Pathogenesis • Majority • atherosclerosis-related thrombosis • At the level of the lamina cribrosa • Other causes • Arterial spasm • Dissecting aneurysm • GIANT CELL ARTERITIS • 1% of cases • Check ESR in elderly patients! • Start high does steroids if suspicious
Central Artery Obstruction • Management • No good therapy exists, all treatments questionable • Ocular message • Anterior chamber paracentesis • Attempt to acutely reduce IOP • Dislodge thrombosis • Inhalation therapy • 95%O2, 5%CO2 • Stimulate vasodilatation • Iris neovascularization • Occurs in 18% of eyes • 1-12 weeks later (usually 3-4 weeks later) • Full PRP treatment required
Branch Retinal Artery Obstruction • Characteristics • Vision loss • Visual filed defect • Within hours/days • Edematous opacification of the retina • In the distribution of the affected vessel
Branch Retinal Artery Obstruction • Pathogenesis • Embolization or thrombosis of vessel • Three types of emboli • Cholesterol • Hollenhorst plaques • Arise from carotid • Platelet-fibrin • Associated with arteriosclerosis • Calcific • Diseased cardiac valves
Retinal Embolization • Hollenhorst plaque • Glistening cholesterol emboli • Found within retinal arteriole • Typically lodge at bifurcations • Arise in carotid arteries
Retinal Embolization • Hollenhorst plaque • Glistening cholesterol emboli • Found within retinal arteriole • Typically lodge at bifurcations • Arise in carotid arteries
Branch Retinal Artery Obstruction • Other causes of BRVO • Migraine • Particularly in smokers • Trauma • Coagulation disorders • Sickle cell disease • Oral contraceptive use • Smoking, older women • Mitral valve prolapse • Infections • Toxoplasmosis, syphilis • Giant cell arteritis • Check ESR in elderly patients • Good prognosis
Workup • ESR,CBC and C-reactive protein • Fasting blood sugar • Glycosylated hemoglobin • Doppler US for carotid artery • ECG, echocardiogram • Refer for haematology
Mortality/Morbidity • Further emboli to the brain resulting in CVA • 55% death over 10 years • 27% age matched population • Further emboli to same or contralateral eye resulting in further visual loss • Progression of temporal arteritis
All four quadrants Central Retinal Vein Occlusion • Findings • Dilated and tortuous retinal veins • Swollen optic disc • Intra-retinal hemorrhages • Retinal edema
Central Retinal Vein Occlusion • Classification • Based on amount of non-profusion on fluorescein angiography • Ischemic • ≥10 disk areas • Non-ischemic • < 10 disk areas • Indeterminate • Too much hemorrhage to tell • 80% progress to ischemic
Central Retinal Vein Occlusion • Pathogenesis • Thrombosis of the central retinal vein • At or posterior to the lamina cribrosa • Atherosclerotic central retinal artery • Impinges on central retinal vein • Turbulent flow → thrombus
Central Retinal Vein Occlusion • Non-ischemic CRVO • Less dilation and vascular tortuosity • Dot and flame hemorrhages in all quadrants • Less or no disk swelling • Angiogram shows • Delayed A-V transit time • Leakage • Minimal capillary dropout • Neovascularization is rare
Central Retinal Vein Occlusion • Ischemic CRVO • Extensive hemorrhage • Retinal edema • Marked venous dilation • Cotton-wool spots • Angiogram show • Widespread capillary nonprofusion • Visual prognosis poor • Only 10% have >20/400 vision • NVI • As high as 60% of eyes • Occurs 3-5 months post occlusion • “the three month glaucoma”
Central Retinal Vein Occlusion • Risk Factors • Eye Disease Case-Control Study • Hypertension • Diabetes • Unlike BRVO • Glaucoma • Check and treat IOP! • CRVO in young patients requires more extensive workup for cause
Systemic vascular disease Hypertension Diabetes mellitus Cardiovascular disease Blood dyscrasias Polycythemia vera Lymphoma Leukemia Clotting disorders Activated protein C resistance Lupus anticoagulant Anticardiolipin antibodies Protein C Protein S Antithrombin III Paraproteinemia and dysproteinemias Multiple myeloma Cryoglobulinemia Vasculitis Syphilis Sarcoidosis Autoimmune disease Systemic lupus erythematosus Oral contraceptive use in women Other rare associations Closed-head trauma Optic disc drusen Arteriovenous malformations of retina CRVO In Young Patients – Causes
Central Retinal Vein Occlusion • Management • Family medical doctor to manage • Hypertension • Diabetes • Elevated cholesterol
Central Retinal Vein Occlusion • Management • Macular edema • Central Vein Occlusion Study Group • Grid laser treatment in the macula • DOES reduce angiographic evidence of edema • DOES NOT improve vision
Central Retinal Vein Occlusion • Management • Macular edema • Intravitreal trimcinolone/Avastin • Capable of transiently improving vision • Risks • Glaucoma • RD • Cataract • Endopthalmitis
Central Retinal Vein Occlusion • Management • Iris neovascularization • PRP to eyes prior to NVI • NO benefit • Even if very ischemic • Once neovascularization detected • Prompt PRP
Central Retinal Vein Occlusion • Outcome • Most important predictor is initial visual acuity: • 20/40 or better • Likely to remain unchanged • 20/400 or less • Likely to remain worse than 20/400 • 20/50-20/200 • 1/3 unchanged • 1/3 improve • 1/3 worse
Branch Retinal Vein Occlusion • Findings • Within one sector of the retina • Superficial hemorrhages • Retinal edema • Cotton-wool spots • Dilated and tortuous vein • Corresponding artery narrowed and sheathed
Branch Retinal Vein Occlusion • Findings • Superotemporal quadrant most common • 63% • Occurs at arteriovenous crossing • Artery and vein bound together in a common sheath • Arterial thickening compresses vein • Turbulent flow → thrombus formation
Branch Retinal Vein Occlusion • Risk factors • Identified by the Eye Disease Case-Control Study • Hypertension • Cardiovascular disease • Increased BMI at age 20 • Glaucoma • Note : Diabetes not an independent risk factor
Branch Retinal Vein Occlusion • Visual Loss • Acute • Macular hemorrhage • Macular edema • Capillary occlusion • Chronic • Macular ischemia • CME • Macular pigmentary changes • Epiretinal membrane formation • Subretinal fibrosis
Branch Retinal Vein Occlusion • Photocoagulation • Used to treat: • Macular edema • Requires intact foveal perfusion • Neovascularization • Macular edema • Allow three months for improvement • Vision 20/40 or worse • Light grid pattern of laser spots to involved sector of retina • Branch vein occlusion study • Treated eyes more likely to gain 2 lines of vision • Treated 65%, untreated 37%
Branch Retinal Vein Occlusion • Photocoagulation • Neovascularization • BVOS defined ischemic BRVO • Area of non-profusion > 5 disk diameters • Large areas of non-profusion increase risk of neovascularization • Apply scatter PRP to areas of retinal ischemia • Only when neovascular complications develop • NVI, NVE, NVD
Branch Retinal Vein Occlusion • Photocoagulation • Must differentiate • Neovascular tissue • Leaks on fluorscein angiogram • Collateral vessels • Help to reduce vascular tissue • Do not treat Vascular Remodeling