Abstract

A stroke is a focal neurological defect caused by haemorrhage or infarction in the brain or brain-stem and lasting longer than 24 hours. Most infarcts are due to atheromatous vascular disease or emboli. A stroke must be distinguished from a transient ischaemic attack (TIA)¹ in which the symptoms last less than 24 hours. At the onset this may be impossible, but most TIAs begin to improve within minutes and have often recovered by the time the patient sees a doctor, when the diagnosis is usually apparent. If the diagnosis is in doubt the patient should be kept under observation.