What is it?

Occlusion and stenosis of precerebral arteries include the basilar artery, carotid artery and vertebral artery. Those are the arteries that supply blood to the circle of willis, which is the joining area of several arteries in the brain. When one of these arteries becomes occluded, the blood supply to a certain area of the brain is reduced, this may lead to a stroke. When the stenosis is temporary, and symptoms go away within the first 24 hours, it is called transient ischemic attack (TIA). The narrowing is caused by a buildup and hardening of fatty deposits called plaque. This process is known as atherosclerosis. The internal carotid artery supplies the front area of the brain, the vertebral and basilar arteries supply blood to the back areas. Risk factors include diabetes, high blood pressure, high cholesterol, obesity, heart diseases, family history, moyamoya disease, arterial dissection, Fibromuscular dysplasia and Takayatsu’s arteritis.