Stroke

Introduction

Stroke is defined as rapidly developing clinical signs of disturbances of cerebral function lasting more than 24 hours with no apparent cause other than one of vascular origin. It may be caused by a haemorrhage secondary to arterial rupture, but more often the cause is ischaemia which occurs if the blood supply to the brain is cut off, due to an embolus or thrombosis blocking an artery. As neurons  are starved of oxygen, they rapidly begin to die and the brain becomes damaged at the site of attack. Body functions such as speech, movement, vision and memory may be affected within minutes. If the symptoms disappear within 24 hours, the condition is defined as a Transient Ischaemic Attack (TIA).