Correlation Between the Visual Acuity and the OCT Pattern of Macular Edema Secondary to Retinal Vein Occlusion

Central retinal vein occlusion (CRVO) is a common retinal vascular disorder. Clinically, CRVO presents with variable visual loss; fundus may show retinal hemorrhages, dilated tortuous retinal veins, cotton-wool spots, macular edIn view of the devastating complications associated with the severe form of CRVO, number of classifications were described. All of classifications take into account the area of retinal capillary nonperfusion and development of neovascular complications.

CRVO can be divided into 2 clinical types, ischemic and nonischemic. In addition, a number of patients may have an intermediate presentation with variable clinical course. On initial presentation, it may be difficult to classify a given patient, since CRVO may change with time.

A number of clinical and ancillary investigative factors are taken into account for classifying CRVO:

Nonischemic CRVO is milder form of disease. It may present with good vision, few retinal hemorrhages and cotton-wool spots, no relative afferent pupillary defect, and good perfusion to the retina. Nonischemic CRVO may resolve fully with good visual outcome or may progress to the ischemic type.

Ischemic CRVO is the severe form of the disease. CRVO may present initially as the ischemic type, or it may progress from nonischemic. Usually, ischemic CRVO presents with severe visual loss, extensive retinal hemorrhages and cotton-wool spots, presence of relative afferent pupillary defect, poor perfusion to retina, and presence of severe electroretinographic changes. In addition, patients may end up with neovascular glaucoma and a painful blind eye.