Which type of stroke is caused by a blockage of blood flow to the brain?

• A. Hemorrhagic stroke
• B. Ischemic stroke
• C. Transient ischemic attack (TIA)
• D. Thrombotic stroke

Answer: (B)

Ischemic stroke is characterized by a blockage of blood flow to the brain, which typically results from a clot obstructing a blood vessel. This blockage prevents essential nutrients and oxygen from reaching brain tissue, leading to cell damage or death in the affected area. The term "ischemic" specifically refers to a reduction in blood supply, and in the context of strokes, it distinguishes this type from others that involve bleeding, such as hemorrhagic strokes, where a blood vessel ruptures.

In addition to ischemic strokes, the term encompasses related conditions like thrombotic strokes, which are a subtype where blood clots form in arteries supplying blood to the brain. While a transient ischemic attack (TIA) represents a temporary blockage of blood flow, it is not considered a stroke since it does not result in permanent damage. In contrast, hemorrhagic strokes involve bleeding rather than blockage, making ischemic strokes unique in their cause of reduced blood flow to the brain.