Treatment of Macular Edema Due to Central Retinal Vein Occlusion

Abstract

Central retinal or hemiretinal vein occlusion, due to a thrombus at an arteriovenous crossing within the optic nerve, is a common disease of the retinal vasculature, the blood supply to the inner layers of the retina that are closest to the vitreous cavity. Central retinal vein occlusion sometimes has been described as a “blood and thunder” appearance due to extensive flame-shaped hemorrhages throughout 2 (hemiretinal) or 4 quadrants of the retina and causes sudden vision loss in one eye when venous flow is acutely compromised. The vision loss at first may be due in part to blood that has extravasated into the retina, but as this blood clears, vision loss may be due to ischemia or infarction of the inner retina due to nonperfusion of retinal capillaries that feed into the occluded retinal veins, as well as complications of abnormal vascular endothelial growth factor (VEGF) produced by the damaged retina. These complications include the development of edema in the center of the retina, or macular edema, which, if left untreated, can cause substantial vision loss. In a pooled analysis using individual population-based data of fundus photographs from 11 studies (n = 49 869), the age- and sex-standardized prevalence was 0.08% (95% CI, 0.06%-0.10%) for central retinal vein occlusion, although the proportion of cases with macular edema, while generally considered to be common, was not reported