FLOW-VOLUME CHANGES IN THE MAJOR CEREBRAL-ARTERIES BEFORE AND AFTER CAROTID ENDARTERECTOMY - AN MR-ANGIOGRAPHY STUDY

Objectives: To characterise changes in blood flow in the major cerebra l arteries before and after carotid endarterectomy (CEA). Design: Pros pective, non-randomised, observational study. Materials: Twenty-nine p atients with symptomatic, unilateral, severe stenosis of the internal carotid artery (ICA) undergoing CEA and 16 control subjects. Methods: Quantitative blood flow volume measurement using magnetic resonance an giography (MRA) on both symptomatic and asymptomatic sides in the comm on carotid artery (CCA), ICA, and middle cerebral artery (MCA) and in the basilar artery, I week before and 3 months after CEA. Results: Bef ore CEA, blood flow was decreased on the symptomatic side in the CCA, ICA, and MCA as compared to the contralateral side and to control subj ects (p<0.001). After CEA, flow on the symptomatic side in the CCA, IC A, and MJCA was increased to normal level (p<0.005) and flow in the ba silar artery was decreased to normal level (p<0.005). Conclusions: The se results demonstrate that arterial blood flow to the symptomatic hem isphere is decreased in patients with severe ICA stenosis. CEA restore s arterial blood flow, rendering cerebral bloodflow less dependent on collateral flow through the basilar artery. MRA flow measurements prov ide new insight in the complex haemodynamcis of the extra-and intracra nial circulation.