A stroke is the result of injury to the brain due to an interruption of blood flow or bleeding from a blood vessel in the brain. Every person who suffers a stroke, however mild, is changed forever. Much is now known about the causes of stroke, and many strokes can be prevented. Knowledge of the causes and symptoms of stroke is the key to prevention.
TYPES OF STROKE
There are two types of stroke. An ischemic stroke is the most common type, and is due to an interruption of blood flow to the brain. It can be caused by a clot that forms in a blood vessel or an artery.
The other main category of stroke, called hemorrhagic stroke, occurs when an artery in the brain leaks or ruptures. Intracerebral hemorrhage is the term for bleeding into the brain. It is commonly, although not exclusively, associated with hypertension. Subarachnoid hemorrhage is the term for bleeding at the base of brain, most often due to rupture of a brain aneurysm. Although the least common type of stroke, it is the most devastating, sometimes resulting in sudden death.
WHAT ARE THE SYMPTOMS OF STROKE?
Signs of a stroke may include:
- Sudden numbness or weakness of the face, arm or leg;
- Inability to speak or understand speech;
- Loss of vision, usually in one eye;
- Sudden dizziness or loss of balance or· coordination. If you experience any symptoms lasting more than 15 minutes, a stroke may be occurring.
WHAT ARE THE RISK FACTORS FOR STROKE?
Several factors are known to place a person at an increased risk for stroke. The single most important risk factor for is hypertension, or high blood pressure. Smoking, diabetes, and elevated cholesterol are also important factors. An irregular heartbeat can play a role in some strokes. Birth control pills may contribute to the risk in young women. Obesity contributes to the risk by promoting some of these factors.
WHAT IS A TIA?
TIA stands for transient ischemic attack. A TIA is a temporary disturbance of neurological function caused by an interruption of blood flow to the brain. Signs of a TIA are similar to those of a stroke. Most TIAs last less than 15 minutes, and tend to resolve themselves. Even though the symptoms disappear after a short time, a TIA can be a strong indicator of a future stroke and should be evaluated by a physician without delay.
HOW SHOULD A TIA/STROKE BE EVALUATED?
Your physician will conduct a series of diagnostic tests to help determine the cause of the stroke or TIA, and to select the appropriate therapy. Blood tests, including a test to determine cholesterol levels, will be performed. A CT scan or MRI of the brain may be performed to evaluate damage and to further study the circulation of blood. An ultrasound of the carotid arteries in the neck may also be performed. Medications such as blood thinners or drugs such as aspirin may be prescribed. If narrowing of the carotid artery in the neck is determined to be the cause, surgery or an endovascular procedure may be indicated.
If a stroke is in progress, immediate treatment in a hospital emergency room that has a stroke program may minimize and/or prevent further progression. Eligible patients can receive a clot-dissolving medication, known as tissue plasminogen activator (t-PA) within the first three hours of the onset of symptoms.
If you are experiencing the symptoms of a stroke, seek immediate medical attention in a hospital emergency room. Do not call your personal physician. Time is the most important factor in stroke treatment.