This case report intends to focus attention on hemodynamic TIAs as cau
se of repetitive involuntary movements (RIMs) as differential diagnosi
s of simple partial motor seizures,We report two patients with episodi
c unilateral limb shaking lasting up to several minutes and which coul
d be triggered by orthostasis, heat or physical exertion, Repeated EEG
recordings revealed no epileptic discharges. In both patients,duplex
ultrasonography revealed an occlusion of the internal carotid artery (
ICA) contralateral to the side of the RIMs. Blood flow velocities in t
he middle cerebral artery ipsilateral to ICA occlusion were reduced an
d vasomotor reactivity to hypercapnia was absent, After elevation of b
lood pressure both patients became asymptomatic. We suggest that in pa
tients with episodes of RIMs, Doppler sonography and tests of cerebral
vascular reserve capacity should be performed to search fora hemodyna
mic origin of these symptoms.