Stroke Information Page

Table of Contents
What is Stroke?
Is there any treatment?
What is the prognosis?
What research is being done?

What is Stroke?
A stroke happens when blood flow to the brain stops. There are two different kinds of stroke. The most common is an ischemic stroke, caused by a blood clot that blocks a blood vessel or artery in the brain. The other, less common, is a hemorrhagic stroke, caused when a blood vessel in the brain ruptures and spills blood into the surrounding tissue. Brain cells in the area begin to die, either because they stop getting the oxygen and nutrients they need to function, or they are killed by the rupture of the vessel and sudden spill of blood.

The symptoms of stroke happen immediately:

• Numbness or weakness in the face, arms, or legs (especially on one side of the body)
• Confusion, difficulty speaking or understanding speech
• Vision disturbances in one or both eyes
• Dizziness, trouble walking, loss of balance or coordination
• Severe headache with no known cause

If you or someone else has these symptoms, seek immediate medical assistance. The longer blood flow is cut off to the brain, the greater the potential for permanent damage.

Doctors diagnose stroke by performing a short neurological examination, as well as blood tests, CT scans, MRI scans, Doppler ultrasound, and arteriography, if needed.

Is there any treatment?
Ischemic strokes can be treated with a drug called t-PA that dissolves the clot or clots that are keeping blood from flowing to the brain. Because damaged brain cells can linger in a compromised but potentially viable state for several hours, the sooner treatment begins the better the chances of surviving without disabilities.

Stroke appears to run in some families who may either have a genetic mutation that predisposes them to stroke, or share a lifestyle that contributes to stroke risk factors. Other than genetic predisposition, additional risk factors for stroke are high blood pressure, heart disease, smoking, diabetes, and high cholesterol. Controlling these risk factors can decrease the likelihood of stroke.

What is the prognosis?
The effects of a stroke range from mild to severe depending on the type of stroke, area of the brain affected, and the extent of the damage. Those who have survived a stroke may experience paralysis, pain, or numbness, as well as problems with thinking and speaking, and emotional changes. Many individuals will require physical therapy to regain strength and mobility, and occupational therapy to relearn how to perform everyday activities, such as eating, dressing, using the bathroom, etc. Speech therapy is appropriate for those who have trouble reading, understanding speech, or forming language.

What research is being done?
NINDS-sponsored research investigates the full range of factors involved in stroke incidence, treatment, diagnosis, and prevention. Current programs are exploring the genetic origins of stroke predisposition, the prevalence of stroke among different racial and cultural groups in America, clinical applications of new therapies, and basic science studies to understand the biological mechanisms involved in the death or survival of brain cells during stroke.

For example, a recent clinical trial showed that aspirin is just as effective as a more expensive medication called warfarin for preventing additional strokes. Prior to this study, most clinicians believed that warfarin was a better blood thinner than aspirin, even though it was more expensive, required monthly blood tests for proper monitoring, and had a greater risk of side effects. The findings from this trial demonstrated that aspirin was not only cheaper and safer than warfarin for preventing stroke, it was just as effective.

Another study used a vaccine that interferes with inflammation inside blood vessels to reduce the frequency and severity of strokes in animal subjects that had high blood pressure and a genetic predisposition to stroke. Researchers are hopeful that the vaccine will work in humans, and could be used to prevent many of the strokes that occur each year in individuals with high risk factors.

Researchers are also looking at how chemicals present in the brain can be used to heal damaged brain cells after a stroke occurs. The findings from a study that used one of these natural chemicals in animal models showed that it could improve motor skills after a stroke by stimulating undamaged nerve fibers to grow new connections in the brain and spinal cord.