Abstract: Platelet aggregation(PA)studies were conducted in 53 cases of cerebral hemorrhage and 23 cases of cerebral ischemia,using ADP-induced in vitro aggregation testing and turbidimedric recording.51 normal controls were also tested.PA mean values in cerebral hemorrhage were far below normal in contrast to the values in cerebral ischemia.The difference was statistically significant, raising the point that abnormalities in platelet aggregation in different types of strokes have meaningful importance,and this study can contribute to the prevention,diagnosis and therapy of cerebrovascular diseases.

Key words: platelet aggregation, ischemic, hemorragic