Carotid arteries are the main blood vessels in your neck that send blood to your eyes and brain. There are two carotid arteries in your neck: one on the right side and one on the left side. Carotid artery disease is when blood flow through your carotid artery is blocked. Without enough oxygen from blood, your eyes and brain do not work properly. You may notice that one side of your body is weak or numb, and you may lose vision on this side of your body.
