Stroke occurs when blood flow through the brain is disrupted and brain tissue becomes damaged.
Stroke is generally caused by a blockage in an artery; however, there are other causes, including a brain hemorrhage (bleeding). Stroke is the third leading cause of death in the United States. Death is only part of the picture though; stroke is the leading cause of severe, long-term disability.
Facts About Strokes
Here are some facts about strokes:
- Each year, approximately 795,000 people in the United States suffer a stroke. About 600,000 of these are first attacks and 185,000 are recurrent attacks.
- On average, every 40 seconds, someone in the U.S. has a stroke. On average, every 4 minutes, someone in the U.S. dies from stroke.
- United States mortality data from 2007 indicate that stroke was the cause of about 1 of every 18 deaths.
- The stroke death rate fell 34.8% from 1998 to 2008.
- Stroke is the leading cause of serious, long-term disability in the United States.
- According to the Framington Heart Study by the National Heart, Lung, & Blood Institute, 50-70% of stroke survivors gain functional independence. 15-30% of survivors are permanently disabled.
- The Framington Heart Study showed that 14% of persons who survive a first stroke have another within 1 year.
- The effects of a stroke primarily depend on the location of the stroke within the brain and the amount of tissue affected. For example, if stroke occurs at the back of the right side of the brain, it’s likely that vision will be impaired.
Types of Stroke
There are two main types of stroked ischemic and hemorrhagic.
Ischemic strokes, which account for approximately 83% of all strokes, occur when a blood vessel in the brain becomes obstructed, typically from a blood clot, and blood cannot reach part of the brain. The underlying cause of the clot is often the fatty deposits that line the artery walls as a result of atherosclerotic disease. The fatty deposits break off and can lodge in blood vessels in the brain. The blood clot may originate from fatty deposits in the vessels of the brain, or from vessels elsewhere in the body.
Ischemic strokes account for approximately 83% of all strokes. They occur when a blood vessel in the brain becomes obstructed, typically from a blood clot, and blood cannot reach part of the brain. The underlying cause of the clot is often the fatty deposits that line the artery walls as a result of atherosclerotic disease. The fatty deposits break off and can lodge in blood vessels in the brain. The fatty deposits may originate in the vessels of the brain or from vessels elsewhere in the body.
Blood clots may also form in the heart as a result of an irregular heartbeat, known as atrial fibrillation. If blood clots form as a result of this condition, they may break off and lodge in the arteries in the brain.
Transient Ischemic Attack (TIA) A transient ischemic attack (TIA) is a “mini” ischemic stroke that occurs when blood flow is blocked for only a short time. The neurologic symptoms clear up in minutes to hours. A TIA should be taken seriously as it’s a warning sign that something is wrong. Many people who experience a TIA may have a full stroke if the cause of the TIA is not treated in a timely fashion.
Hemorrhagic strokes account for about 17% of stroke cases. They occur when a weakened blood vessel ruptures and blood saturates the surrounding brain tissue. An aneurysm is a type of hemorrhagic stroke where a blood vessel balloons and weakens until it ruptures. An arteriovenous malformation (AVM) is an uncommon condition where an abnormally formed blood vessel ruptures.
Risk Factors for Stroke:
Everyone has some stroke risk. While you can’t eliminate some risk factors, others are under your control. If you have risk factors beyond your control, such as your age or gender, it is even more important that you alter your lifestyle to reduce manageable risks.
- Age 55 or older
- Family or personal history of stroke or TIA
- History of atrial fibrillation
- Being African American, Asian, American Indian, Mexican American, or an Alaska Native
- High cholesterol
- High blood pressure
- Heart disease
- Carotid or other artery disease
- Certain blood disorders, including Sickle Cell Anemia
- Over-consumption of alcohol
- Obesity and physical inactivity
Reducing the Risk
While many risk factors for stroke are beyond your control, there are some ways you can reduce your risk of stroke:
- Know your family history of stroke and share it with your primary care provider
- Maintain a healthy body weight
- Get enough exercise
- Eat a healthy diet to prevent or reduce high blood pressure and high cholesterol
- Stop smoking
- Limit alcohol consumption
- Follow your healthcare provider’s instructions for controlling diabetes
- Follow your healthcare provider’s instructions for stroke prevention
Warning Signs of Stroke
A stroke or aneurysm is a medical emergency that must be treated quickly. If you experience any of the following warning signs, call 911 and get to a hospital immediately:
- Sudden numbness or weakness in the face, arm or leg (especially on one side of the body)
- Sudden confusion, trouble speaking or understanding
- Sudden trouble seeing in one or both eyes
- Sudden dizziness, trouble walking, or loss of balance or coordination
- Sudden, unexplainable and intense headache
- Sudden inability to move part of the body (paralysis)
Doctors may diagnose a stroke by various means, including imaging exams. Radiology Imaging Associates offers the following imaging techniques. These are some of the most current techniques available, allowing for the detection of stroke in its earliest phase.
- Cerebral Angiography
- Brain Perfusion and Brain Diffusion
Treating this Condition
Radiology Imaging Associates’ radiologists perform the most current procedures for the minimally-invasive treatments of stroke and aneurysm.
- Stoke therapy using mechanical clot removal is a new procedure approved by the FDA in August 2004. It allows a blood clot to be retrieved from a blood vessel so blood flow can be restored
- Intracranial balloon angioplasty and intracranial stenting can be performed to restore blood flow within the brain
- Aneurysm coil embolization is used to treat arteries that have ballooned to prevent rupture
- AVM embolization is used to block abnormal vessels in an AVM or DAVF to prevent rupture