Objective To compare the effects of cilostazol on cerebral arteries and cerebrovascular blood flow in secondary prevention of ischemic stroke, with those of aspirin. Methods Sixty-eight patients who had ischemic stroke during the recent 1-6 months were recruited and randomized into cilostazol or aspirin group. Cerebrovascular condition was assessed by magnetic resonance angiography （MRA） and transcranial doppler ultrasonography （TCD） at the beginning of the study and after 12-month medication. Results During the clinical follow-up, ischemic stroke recurred in 2 patients in cilostazol group, while in aspirin group, one case of ischemic stroke recurrence and one case of acute myocardial infarction were found. MRA revealed that in aspirin group, the percentages of patients experiencing aggravation and attenuation of cerebrovascular condition were 3.3% and 6.7%, respectively, while in aspirin group, they were 3.3% and 10%, respectively. Moreover, TCD revealed that 26.9% of the patients in aspirin group and 14.3% of the patients in cilostazol group experienced aggravation of cerebrovascular condition. However, the systolic peak flow velocity of the previously abnormal arteries increased by 42.9% after 12-month medication of cilostazol, which was significantly higher than that after aspirin medication （27.5%） （P = 0.04）. Furthermore, as a major side effect of antiplatelet therapy, the frequrency of bleeding was much less in cilostazol group （0 case in cilostazol group vs 5 in aspirin, P 〈 0.05）. Conclusion Cilostazol is as effective as aspirin in preventing the aggravation of cerebral arteries in secondary prevention of ischemic stroke. Besides, it is more safe. Cilostazol can increase the systolic peak flow velocity of cerebral arteries, which may improve the blood supply of focal ischemia.
