A stroke, also known as a cerebrovascular accident (CVA), is a medical condition that occurs when blood flow to a part of the brain is disrupted, resulting in damage to brain cells due to lack of oxygen and nutrients. Strokes can be categorized into two main types:
- Ischemic Stroke: This is the most common type of stroke, accounting for approximately 85% of cases. Ischemic strokes occur when there is a blockage or narrowing of a blood vessel that supplies blood to the brain. The blockage is typically caused by a blood clot or plaque buildup in the arteries, reducing or completely obstructing blood flow. The lack of blood flow leads to a lack of oxygen and nutrients, causing damage to brain cells in the affected area.
- Hemorrhagic Stroke: Hemorrhagic strokes occur when a blood vessel in the brain ruptures and causes bleeding into the surrounding brain tissue or the spaces around the brain. This can result from a weakened blood vessel wall, such as an aneurysm (a bulge in a blood vessel) or arteriovenous malformation (AVM), or it can be caused by high blood pressure that weakens the blood vessel walls over time. The bleeding puts pressure on the brain, damaging brain cells.
Strokes can cause a wide range of symptoms depending on the area of the brain affected. Common symptoms include sudden weakness or numbness on one side of the body, difficulty speaking or understanding speech, vision problems, severe headache, dizziness, loss of balance or coordination, and confusion.
Strokes are medical emergencies that require immediate medical attention. Early intervention and treatment can minimize brain damage, improve outcomes, and increase the chances of recovery. Recognizing the signs and symptoms of stroke and seeking prompt medical care is crucial for the best possible outcome.