Me and Mines

.What is Ischemia? Infarction?

Ischemia is a medical term for an insufficient amount of blood flow or supply to a specific part of the body. This will in turn cause a reduced supply of oxygen. If the supply of oxygen is cut off to where it can not reach an area of the body at all, it was case Infraction. Infarction is the when an area of the tissue dies due to a sudden lack of oxygen caused by a complete loss of the tissues blood supply.

2.What is a stroke? Describe the mechanism(s) by which strokes occur.

A stroke is a type of cerebrovascular disease that involves the vessels of the central nervous system. Also called an apoplexy, or referred to as a "brain attack", a stroke is when there is a sudden impairment of brain function due to an interruption in the supply of blood to the brain. There are two main types of strokes. An Intracranial Hemorrhage and an Ischemic Stroke. A stroke will occur when a blood vessel breaks or bursts or when a blood clot blocks off an artery. Either way it is interrupting the flow of blood to an area of the brain. This means that brain cells begin to die which causes a loss of brain function or even brain damage.

An Ischemic stroke occurring in the anterior circulation are the most common of all strokes. They are caused mostly by occlusion of one of the major intracranial arteries or of the small single perforator (penetrator) arteries.

The main mechanisms leading to an ischemic stroke are decreased perfusion, embolism, hemorrhaging and thrombosis.

The blockage of an artery in the brain by a clot is thrombosis.

Narrowing of the small arteries and blood vessels is decreased perfusion.

Hardening of the arteries, or atherohsclerosis, along with plaque and/or cholesterol build up; can cause narrowing of arteries which may result in debris within to break off, clog and rupture. This can cut of blood supply from these arteries to large areas of the brain; or Embolism to the brain from the heart. Rupture of an artery...