An eye occlusion, or stroke, is the blockage of a vein that causes the body to lose its ability to drain blood from the retina, leading to bleeding and leakage from blocked blood vessels, notes Cleveland Clinic. People displaying the symptoms of an eye occlusion should seek medical help immediately, as the condition can lead to permanent eye damage.
Central retinal vein occlusion is a blockage of the main retinal vein, while branch retinal vein occlusion is a blockage of one of the branch veins, states Cleveland Clinic. Eye veins that are too narrow can cause eye occlusions, and people with diabetes or who have conditions that affect blood flow are at higher risk of contracting the condition. Blurring and loss of vision are symptoms of an eye occlusion, which usually occurs in only one eye. The symptoms gets worse over the course of hours or days, and in some cases people with eye occlusions suffer an immediate, complete loss of vision in the affected eye.
Eye occlusions can cause vision-threatening conditions such as macular edema, in which blood and fluid leak into the macula, the central area of the retina that controls detailed vision, notes Cleveland Clinic. Eye occlusions may also lead to neovascularization, or the development of new, abnormal blood vessels that may leak blood into the vitreous of the eye. Neovascular glaucoma occurs when new blood vessels in the eye cause pain and increased risk of increased pressure in the eye.