Your heart pumps oxygen and nutrient rich blood to the rest of the body, including the brain. The brain depends on a steady supply of blood to function properly. If the brain does not receive its oxygen and nutrients, affected areas of the brain may be damaged, which can disrupt body function. Problems with the vessels that supply blood to the brain can block blood flow and greatly damage the brain.
Blood vessels called arteries carry blood from the heart to the body. The carotid arteries are the major arteries in your neck that supply your brain with blood. The common carotid arteries are located on both sides of the neck, and both divide into two branches. The internal carotid artery brings blood to the brain while the external carotid artery brings blood to the face and scalp.
Healthy carotid arteries have smooth walls and are unobstructed, enabling blood to flow easily to the brain. They provide the brain with enough blood to function properly.
A damaged artery no longer has a smooth lining, but rather a substance called plaque accumulates along its walls, so called “hardening of the arteries”. Plaque is formed when cholesterol and other particles in the blood stick to the artery wall. The buildup of plaque causes the artery to narrow, called stenosis. Stenosis reduces the blood flow to the brain. Artery damage can be caused by smoking, diabetes and high blood pressure. It also may be hereditary.