Abstract:Transcranial Doppler Sonography(TCD),Cerebrovascular Hemodynamics Analyzer(CBA)and Magnetic Resonance Imaging(MRI)were performed in migraine patientswithout aura during the headache-flee period.TCD examination in 40 patients showed significantly elevated mean flow velocities in bilateral middle cerebral arteries,and markedasymmetry of MFV mean flow velocity in corresponding intracranial arteries was found in 9patients.The results of CBA in 44 Patients revealed elevations of cerebral vascular resistance,dynamic resiStance and critical pressure.Taken together,these results suggest intracranial vasotonus and instable vascular tone of migraineurs without aura in the interictalperiod.Besides,MRI of the brain in 6 out of 10 patients showed multiple ischemic lesions orlacunar infarction.It is to be determined in the future whether these morphological changesare due to long-term vascular abnormality in migraine P8tients.