Which finding differentiates central retinal vein occlusion from central retinal artery occlusion?

• A. Retinal whitening is present in CRVO
• B. Boxcar segmentation of blood in retinal veins is more typical of CRVO
• C. Retinal hemorrhages are not seen in CRVO
• D. Retinal hemorrhages are present in CRVO

Answer: (D)

A key distinction between central retinal vein occlusion and central retinal artery occlusion is how the retina appears due to the different blood flow problems. An artery occlusion causes sudden ischemia of the retina, leading to a pale, edematous retina with a cherry-red spot at the fovea and little or no widespread hemorrhage. In contrast, a vein occlusion leads to venous congestion and rupture of fragile capillaries, producing widespread retinal hemorrhages with edema—the classic “blood and thunder” appearance. Because CRVO shows intraretinal hemorrhages throughout the retina while CRAO does not, the presence of retinal hemorrhages is the finding that differentiates CRVO from CRAO.