An ischaemic stroke occurs when there is a blockage or obstruction in a blood vessel that supplies blood to the brain. The blockage leads to a significant reduction or complete cessation of blood flow to a part of the brain, resulting in damage to brain tissue due to the lack of oxygen and nutrients. Ischaemic strokes are the most common type of strokes, accounting for about 87% of all stroke cases.

Unit 1,

Reference: Oxford Concise Medical Dictionary (9th ed) Oxford University Press 2015 ISBN-13: 9780199687817, p2412