Avicenna on the causes and signs of stroke.

Ancient and medieval theories on the causes and signs of stroke are presented in a translation of the relevant chapters of the Canon of Medicine by Avicenna (908-1037 A.D.), which was one of the main books studied by doctors for nearly 500 years. Recognised aetiologic factors included vascular occlusion, cerebral abscess, trauma, and repeated blood-letting. Motor and sensory deficits were described, as was the occasional association with facial palsy, respiratory difficulty, and coma. Warning symptoms such as severe headache and blackout were known, as was the poor prognosis associated with stroke that follows severe headache. Obesity as a risk factor was identified.