Effect of Cilostazol in the Acute Lacunar Infarction Based on Pulsatility Index of Transcranial Doppler

Inclusion Criteria: * Patients with first ever lacunar infarction within 7 days after the onset of symptoms * Age: more than 45 years of age Exclusion Criteria: * Patients with any contraindications to the treatment with antiplatelet therapy * Patients with potential cardiac embolic source; prosthetic valve, atrial fibrillation, atrial flutter, left atrial/atrial appendage thrombus, sick sinus syndrome, left ventricular thrombus, dilated cardiomyopathy, akinetic or hypokinetic left ventricular segment, atrial myxoma, Infective endocarditis, mitral valve stenosis or prolapse, mitral annuls calcification, left atrial turbulence, nonbacterial endocarditis, congestive heart failure, recent myocardial infarction (within 4 weeks) * Bleeding diathesis * Chronic liver disease (ALT \> 100 or AST \> 100) or chronic renal disease (creatinine \> 3.0mg/dl) * Anemia (hemoglobin \< 10mg/dl) or thrombocytopenia (platelet count less than 100,000/mm3) * Nonatherosclerotic vasculopathy; patients with clinical characteristics suggesting arterial dissection, moyamoya disease, Takayasu's arteritis, radiation associated angiopathy, and other vasculitis. * Pregnant or lactating patients * Patients with hyperthyroidism or COPD * Patients with current anticoagulation or antiplatelet therapy * Patients with poor temporal window in transcranial Doppler