Central retinal vein occlusion is a closure of the final retinal vein (located at the optic nerve), which collects all of the blood after it passes through the capillaries. Most occlusions occur after age 50, although younger patients are sometimes seen with this disorder (in this age group it is often called (papillophlebitis). The highest rate of occurrence is in individuals in their 60’s and 70’s. These disorders are similar to those for vascular occlusive disease elsewhere in the body such as stroke and coronary artery disease. Specifically, aging, high blood pressure, diabetes, and smoking are all risk factors.