Webster Dictionary(0.00 / 0 votes)Rate this definition: Freebase(0.00 / 0 votes)Rate this definition: Crenulation or Crenulation cleavage is a texture formed in metamorphic rocks such as phyllite, schist and some gneiss by two or more stress directions resulting in superimposed foliations.
Retinal vein occlusions typically occur in older patients with a history of high blood pressure and atherosclerosis. Other causes of retinal vein occlusion include vasculitis, clotting disorders, and medications such as oral contraceptive pills.
Retinal vascular occlusion affects the eye, specifically the retina. An occlusion occurs when one of the veins or arteries carrying blood to or from the retina becomes blocked or contains a blood clot.The blockage could occur in the main vein or main artery.Blockages could also occur in the branch of veins and arteries throughout the retina.n occlusion occurs when one of the veins or arteries carrying blood to or from the retina becomes blocked or contains a blood clot. The blockage could occur in the main vein or main artery. Blockages could also occur in the branch of veins and arteries throughout the retina.