Lecture Notes: Central Retinal Vein

Occlusion Non Ischemic and Ischemic

Branch retinal vein occlusion

Hemi Retinal vein occlusion

Types

Prepared BY : Dr.Kausar Ali :

Doctor of optometry* Prepared For :

OD 5th semester .Coming junior classes .Pef university college

peshawar

*Lectures Include:

*Etiology . *Clinical features . *Symptoms . *Signs . *Investigation . *Complication . *Visual prognosis . *Treatment :

*Central Retinal vein occlusion : *Definition:

*Central retinal vein occlusion (CRVO) is a blockage of the main vein in the retina .*The central retinal vein is the venous equivalent of the central retinal artery and, like that blood vessel, it can suffer from occlusion   (central retinal vein occlusion, also CRVO),

*similar to that seen in ocular ischemic syndrome. Since the central retinal artery and vein are the sole source of blood supply and drainage for the retina, such occlusion can lead to severe damage to the retina and blindness, due to ischemia (restriction in blood supply) and edema(swelling).

*Etiology : *Age is the most important factor 50% of cases occur after the age of 60y .*External compression : arteriosclerosis or athero sclerosis of central retinal artery or its branch compresses the vein at lamina cribosa or its branch at arteriovenous crossing because at these two sites the artery and vein have common facial sheath .

*Systemic Hypertension : it is the most common cause of BRVO and is present in up to 73% of cases . *Diabetes mellitus : is present in about 10% of cases . *Raised Intraocular pressure : CRVO is more common in primary open angle glaucoma . *Drugs : oral contraceptive (birth controle pills are used to prevent pregnancy )

*Hyperviscosity of blood > Polycythemia ( An abnormally increased concentration of haemoglobin in the blood .

> Hyperlipidemia ( abnormally elevated levels of any or all lipids and or lipoproteins in the blood . *Thrombophilic disorder .( Thrombophilia is an abnormality of blood coagulation that increases .

> Hyperhomocysteinurea ( is a medical condition characterized by an abnormally high level of homocysteine in the blood, conventionally described as above 15 µmol/L. * Inflammation . > Eales disease (Eales disease is an idiopathic obliterative vasculopathy that usually involves the peripheral retina of young adults) Eales disease ( periphlebitis )

> Saccoidosis (Sarcoidosis, also called sarcoid, is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas)

*Local cause : Orbital cellulitis Cavernous sinus thrombosis .*NON ISCHEMIC CRVO:*Clinical Features : *Is the most common clinical variety 75%*Symptoms : *Sudden onset of unilateral painless deterioration of vision .

*Signs : *Visual acuity : moderate to severe visual loss .*Afferent pupillary defect : is absent or mild .*IOP may be raised e.g in primary open angle glaucoma . *Fundus examination shows : *Spontaneous venous pulsation is absent . *Retinal veins are dilated, engorged and tortuous (Paichida )

*Dot : blot and flamed- shaped haemorrhages are present in all four quadrants and most numerous in periphery .*Cotton whool : spots may be present *Optic disc and macular oedema is mild . *Investigation : *Are carried out to find out the cause to prevent the similar attack in the other eye . See fig ( 1.1 and 1.2 )

Fig 1.1 Fig 1.2

Mild disc oedema . Flamed

shaped haemorrhages ,

Perfusion area

*Blood pressure . *ECG *Blood .. CP and ESR . Blood glucose level . Lipids . plasma protein electrophoresis . ( Fibrinogen, a beta-2 protein) .*Auto Antibodies : ANA (autoimmune disorder, ) Anti DNA(Lupus erythematosus is a name given to a collection of autoimmune diseases ) and ANCA .(Anti-neutrophil cytoplasmic antibodies (ANCAs) are a group of autoantibodies, mainly of the IgG type, )

*Fluorescein angiography shows good capillary perfusion .*Optical coherence tomography OCT to demonstrate the severity of macular oedema and is useful to assess the response of treatment . *Fundus fluorescein angiography FFA is useful to assess the perfusion of retina . *Complication : *Cystoid macular oedema is the main complication .

*Conversion to ischemic type occurs in about 15% cases which progress to rubeosis in about 37% within 4 month. *Visual prognosis : *Heamorrhages resolve within 6 to 12 months . *Visual prognosis is good with return of vision nearly normal in about 50% of cases . *Visual loss in rest of cases is mainly due to cystoid macular oedema .

*Treatment : *Laser photocoagulation for macular oedema is not effective .*Consist of Anti VEGF ( drugs like lucentis or *Intravetral triamcinolone acetonide (Triamcinolone acetonide is known as a corticosteroid hormone (glucocorticoid). It works by decreasing your body's immune response to these diseases and reduces symptoms such as swelling.) *Oral steroid for 8 to 12 weeks may be effective .

*Optic nerve sheathotomy via pars plana approach for decomposing the central retinal vein at lamina cribosa . *ISCHEMIC CRVO:*Clinical features : *Presentation is sudden onset of severe visual loss . *Visual acuity is usually counting fingers or worse .*Afferent papillary defect is marked .

*Intraocular pressure may be raised . *Fundus examination shows :

Non perfusion ischemic area .

*Retinal veins are very tortuous and engorged . *Retinal haemorrhages dot : blot and flamed shaped haemorrhages in all four quadrants of retina and posterior pole ( almost whole fundus is full of heamorrhage giving tomato splashed appearance . *Disc odema and hyperemia is severe . *Cotton whool spot may be present .

*Investigation:*Blood pressure . *ECG *Blood .. CP and ESR . Blood glucose level . Lipids . plasma protein electrophoresis . ( Fibrinogen, a beta-2 protein) .*Auto Antibodies : ANA (autoimmune disorder, ) Anti DNA(Lupus erythematosus is a name given to a collection of autoimmune diseases ) and ANCA .(Anti-neutrophil cytoplasmic antibodies (ANCAs) are a group of autoantibodies, mainly of the IgG type, ) *

*Fluorescein angiography shows good capillary perfusion .*Optical coherence tomography OCT to demonstrate the severity of macular oedema and is useful to assess the response of treatment . *Fundus fluorescein angiography FFA is useful to assess the perfusion of retina.*Prognosis : *Prognosis is extremely poor due to macular ischemia .

*Complication : *Macular ischemia .*Chronic cystoid macular oedema. *Rubeois iridis , which causes neovascular glaucoma NVG in more than 50% cases between 2 to 4 months .*Treatment: *Panretinal photocoagulation PRP is carried out in all eyes rubeosis iridis .*Cryotherapy application when retinal view is not possible due to hazy media .

*Branch retinal vein occlusion : *Branch retinal vein occlusion (CRVO) is a blockage of the Branch vein in the retina .*It is common than central retinal vein occlusion . *Types : *Quadrant vein occlusion major branch away from disc A-V crossing .*Hemiretinal vein occlusion main branch vein occlusion at disc margin .

*Clinical Features : *The oedema and haemorrahages are limited to the retinal area drained by the affected vein . *Vision is affected only when macular area is involved .*Cotton whool spots present . *Secondary glaucoma occur rarely.*Prognosis is reasonable good .

*Complication : *Chronic macular oedema : is common cause for poor vision . *Neovascularization develops in 10% of cases.*Treatment : *Laser photocoagulation : for macular oedema, when macular perfusion is good.*Intravetral steroid triamcinolone acetonide may improve vision . *Intravetral anti VEGF showing good result .