A vein occlusion refers to the blockage of a retinal vein responsible for the outflow of blood from all or parts of the retinal circulation. The most common cause of this blockage is from longstanding hypertension. An occlusion can also be seen in diabetic patients. Less common causes include inflammatory conditions as well as coagulation disorders. A vein occlusion results in hemorrhage and swelling of the retina in the distribution of the blood vessels. Treatment with laser and anti-VEGF therapy may be useful in visual recovery as well as prophylactic for complications associated with more severe vein occlusion such as bleeding or glaucoma.