A Stroke is one of the main causes of adult disability and the third leading cause of death next to cancer and heart disease.
A stroke is often called a brain attack and is caused by the amount of blood in the brain. There are two types of strokes they are as follows:-
- Ischemic Stroke – is attributed to not enough blood in the brain.
- Hemorrhagic Stroke - is attributed to too much blood in the skull.
Ischemic Strokes account for eighty percent of all strokes, which happen when blood clots or other particles block arteries to the brain and restrict the blood flow severely (ischemia) this, deprives the brain cells of oxygen. The most common ischemic strokes are called a thrombotic stroke, they happen when a blood clot (thrombus) forms in one of the arteries that supply the blood to the brain. A clot often forms in an area that has already been damaged by a disease called atherosclerosis (a disease that is caused by arteries that have been clogged by the accumulation of plaque cholesterol –containing fatty deposits;) this can occur within one or two of the carotid arteries in the neck which carries the blood to the brain and other arteries. An Ischemic stroke can also be due to plaque that has completely clogged or narrowed an artery. The narrowing of an artery is called stenosis.
Hemorrhagic strokes happens when a blood vessel in the brain leaks or ruptures. Hemorrhages (a medical word meaning bleeding) are due to several conditions affecting the blood vessels; they are high blood pressure that has not been controlled (hypertension) and weak spots in the walls of the blood vessels (aneurysm.) Another less common cause of a hemorrhage is AVM (a rupture of an anteriovenous malformation) a birth defect of a malformed tangle of thin-walled blood vessels. There are two types of hemorrhage strokes.
- Intracerebral hemorrhage stroke is often caused by high blood pressure that causes small arteries in the brain to become brittle which can cause cracking or a rupture (this causes a blood vessel in the brain to burst and spill into the surrounding brain tissue.
- Subarachnoid hemorrhage stroke occurs when bleeding starts in a large artery near or on the membrane that surrounds the brain (this spills in the space between the surface of the brain and skull.) This type of stroke is often recognized by a severe headache that is often caused by the rupture of an aneurysm that usually happens with age (genetic predisposition.) After this type of stroke blood vessels can go into vasospasm (causing the arteries near the hemorrhage to constrict irrationally) this results in brain cell damage by increasing the restriction and blocking of the blood flow to parts of the brain.
The signs and symptoms of a stroke. (Symptoms usually occur suddenly and frequently and there are usually more than one.)
- Numbness, weakness, paralysis of face, arm, leg or one side of the body.
- Aphasia – difficulty in speaking or the awareness of others speaking.
- Decreased or blurred vision
- Loss of balance, lack of coordination or dizziness
- Severe headache
- Facial pain, stiff neck
- Pain between the eyes
- Altered consciousness and vomiting
If any of the above symptoms occur it is important to obtain medical treatment as soon as possible to ensure that the stroke victim receives prompt treatment to prevent the severity of the stroke causing permanent damage. A transient ischemic attack has the same symptoms as a stroke; they do however only last for a few minutes to twenty four hours and usually disappear without leaving any permanent effects. Some people however may have more than one and should take it as a sign that a full blown stroke could follow.
The good news these days is that fewer people now die of strokes than in the past. The reason for the improvement is in the awareness and the control of major risk factors.
For more information. www.heartandstroke.ca , www.stroke.org, www.mayoclinic.com
