Central and branch retinal vein occlusion are common causes of acute loss of vision, with branch vein occlusions being four times more common. The major predisposing factors are the etiologic factors associated with arteriosclerosis, but glaucoma is also a major risk factor for central and branch retinal vein occlusion.
Ophthalmoscopic signs of central retinal vein occlusion include widespread retinal hemorrhages, retinal venous dilation and tortuosity, retinal cotton-wool spots, and optic disk swelling (Figure 7–3) (eFigure 7–45).
Central retinal vein occlusion.
Ultra-widefield (Optomap) image of central retinal vein occlusion with retinal hemorrhages throughout the retina and a cotton-wool spot (arrow). (Used, with permission, from S Kiss and Optos plc.)
Branch retinal vein occlusion may present in a variety of ways. Sudden loss of vision may occur at the time of occlusion if the fovea is involved, or some time afterward from vitreous hemorrhage due to retinal new vessels. More gradual visual loss may occur with development of macular edema. In acute branch retinal vein occlusion, the retinal abnormalities (hemorrhages, venous dilation and tortuosity, and cotton-wool spots) are confined to the area drained by the obstructed vein (eFigure 7–46) (eFigure 7–47).
Branch retinal vein occlusion.
Fluorescein angiogram of superior temporal branch retinal vein occlusion of left eye showing macular microvascular changes (arrow). (Used, with permission, from S Kiss and Optos plc.)
To assess possible reversible risk factors, check blood pressure and ask about tobacco smoking in all patients, and ask women about estrogen therapy (including combined oral contraceptives). Patients should also be asked about a history of glaucoma and should undergo a comprehensive eye examination to check intraocular pressure and for signs of open- or narrow-angle glaucoma.
Obtain screening laboratory studies for diabetes mellitus, hyperlipidemia, and hyperviscosity (especially in simultaneous bilateral disease), including serum protein electrophoresis for paraproteinemia. Particularly in younger patients, consider obtaining antiphospholipid antibodies, lupus anticoagulant, tests for inherited thrombophilia, and plasma homocysteine levels.
If central retinal vein occlusion is associated with widespread retinal ischemia, manifesting as poor visual acuity (20/200 [6/60] or worse), florid retinal abnormalities, and extensive areas of capillary closure on fluorescein angiography, there is a high risk of development of neovascular (rubeotic) glaucoma, ...