Cerebral Vascular Accident: Stroke
Cerebral Vascular Accident (CVA), also known as stroke, is an acquired brain injury resulting from a sudden alteration in brain function in which weakness, paralysis of a body part, or neurological deficiencies develop due to decreased blood flow to an area of the brain (Falvo, 2009). This condition is often the culmination of progressive disease occurring over the course of many years (Falvo, 2009) with heart disease, hypertension, and diabetes often associated with stroke (Greenberg, 2006).
Falvo (2009) discusses three main causes of stroke. The most common cause is blocking of a cerebral artery by a clot (thrombus) formed inside the artery, a condition referred to as cerebral thrombosis. Formation of the thrombus blocks blood flow to an area of the brain. Brain tissue needs oxygen contained in blood to survive, if tissue cannot obtain needed nourishment because of blockage, then it dies within a short period of time. This tissue death is called an infarct. The amount of damage depends on how large an area of the brain has been deprived of blood supply from the clot.
Another cause of stroke is embolism. In this case a clot forms in another part of the body, then breaks off, traveling through the blood to the brain and lodging in one of the cerebral arteries. Again, when the clot occludes blood flow to a part of the brain, surrounding brain tissue dies. The above examples are referred to as ischemic stroke.
A third cause of stroke is hemorrhage, which occurs because of rupture of a blood vessel. A common cause of cerebral hemorrhage is hypertension (high blood pressure). When blood vessels are weakened from disease, such as with arteriosclerosis, or congenital weakness as with an aneurysm, increased pressure may cause the blood vessel to burst. Death of brain tissue occurs in this instance not only due to a certain area of the brain being deprived of oxygen, but also the escaped blood compresses brain...