Stroke; types, causes, signs and symptoms
Posted on Mar 7 2012 at 10:36:42 AM in Diseases
You probably know of stroke as the disease or condition that renders one side of the body numb and dysfunctional. Well, it is a form of cardiovascular disease that affects the blood supply to the brain.
The blood vessels are usually blocked or ruptured. This disturbs the brain function since the nerves in the brain require continuous supply of blood, oxygen and glucose. The brain does not store any nutrients but uses about 25 percent of the body’s oxygen and 70 percent of the blood sugar. About 30 seconds without blood supply and the brain makes you unconscious.
Stroke is also referred to as cerebral vascular disease or apoplexy. It affects older persons more than the younger generation. usually, those above 50 years of age at a higher risk.
There are several types of stroke. Broadly, there is ischemic apoplexy and haemorrhage stroke.
Ischemic stroke is caused by lack of blood flow to the brain. It is the more common form of apoplexy. It usually occurs due to atherothrombosis, also known as large artery disease; where there is a clot in the vessel supplying the brain. There is embolic apoplexy also known as cerebral embolism which is caused by a wandering clot. The clot usually is composed of calcium, air, blood or platelets. Another type under ischemic is lacunar stroke. This is as a result of complete blocking of arteries in the brain. This has no noticeable symptoms but it is fatal.
Haemorrhage stroke is caused by bleeding in the brain or its adjacent tissues. Blood flows out of a vessel and into the brain. This type happens more in those who have high blood pressure or damaged vessels such as in diabetes and atherosclerosis. It is often preceded by a TIA; occur when blood pressure is low such as in sleep or inactivity. Haemorrhage apoplexy is sometimes accompanied by seizures. When it is caused by an aneurysm, it is referred to as subarachnoid hemorrhage stroke. An aneurysm is an out pouncing of blood in the vessels and it can cause raptures and bleeding.
Stroke has symptoms which depend on which side of the brain was affected. It does not show symptoms in its early stages of development.
Stroke has several risk factors, what causes or aids it development. They include obesity, hypertension, smoking and diabetes. It is also closely associated with heart diseases such as myocardial infractions which are caused by damages on the blood vessels. Other risk factors of stroke are age, sex, drug and substance abuse, over consumption of alcohol, specific contraceptives, sickle cell disease and migraines and headaches.
Heart diseases such as congestive heart failure, atherosclerosis, left ventricular hypertrophy and irregular heart rhythm (aarrhythmias) are at a higher risk of ischemic stroke. When the wandering blood clot travels to the brain and blocks its vessels, that type is referred as cardio embolic stroke. Persons with a history, family or personal of coronary disease are at a higher risk of developing stroke.
Habits such as smoking facilitate the development of atherosclerosis, the deterioration of blood vessels which results to cerebral haemorrhage.
There is a condition referred to as transient ischemic attacks. This is a localized neurological problem caused by a decreased flow of blood. Its symptoms are similar to stroke such as the weakness and numbness of one side, inability to speak, lack of coordination, and the clouding and blurring of the eye. They occur due to blood clot or an altered flow where a vessel is narrowed.
Stroke can only be managed and not treated. The reason why stroke does not heal is because the body does not replace brain cells after they are damaged.