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URL of this page: //medlineplus.gov/ency/imagepages/17133.htm
Stroke
Overview
A stroke involves loss of brain functions caused by a loss of blood circulation to areas of the brain. The blockage usually occurs when a clot or piece of atherosclerotic plaque breaks away from another area of the body and lodges within the vasculature of the brain.
Review Date 6/1/2026
Updated by: Thomas S. Metkus, MD, PhD, Associate Professor of Medicine and Surgery, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.