Abstract #3429

van Laar P, Hendrikse J, van Osch M, van der Grond J, Mali W

It has been forwarded that in patients with severe internal carotid artery (ICA) stenosis, a decrease in blood flow distal to the stenosis contributes to the clinical symptoms. Compensatory processes include the recruitment of collateral arteries, however their actual contribution remains unknown. We studied the flow territories of the extracranial arteries in 24 patients with severe ICA stenosis and 40 control subjects with selective arterial spin labeling. The reversibility of changes was investigated after carotid endarterectomy or stenting. Our data show that prior to intervention, collateral flow indeed significantly contributes to the ipsilateral hemisphere. After carotid desobstruction flow territories normalize.