What Is A Branch Retinal Vein Occlusion?
A branch retinal vein occlusion (BRVO) is a blockage of one of the small blood vessels that drains blood from the retina. The retina is the light-sensitive nerve tissue lining the back of the eye. Like film in a camera, the retina continually “takes pictures” of everything you look at. When part of the retinal vein becomes blocked, the retinal blood flow slows or stops. Suddenly and usually without warning, a patch of retina loses some of its “picture-taking” function and you may be aware that part of your field of vision has darkened. Why Is Vision Lost? Normally, the retina is nourished by oxygen-rich blood that is brought to it by arteries and drained away by veins. When a vein – a drainage channel – is blocked, blood backs up, leading to bleeding and swelling (edema) in the retina which hampers its nourishment. The extent of damage and the visual symptoms produced depend on the size of the blocked vein and its exact location. If the blockage occurs toward the peripheral part of the
