Abstract #1536

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

Patients with occlusion of the internal carotid artery (ICA) strongly rely on collateral pathways to maintain adequate cerebral perfusion pressure. However, the actual contribution of these collateral pathways is still difficult to assess or to quantify. With non-invasive selective arterial spin labeling we studied the extent of the collateral flow territories in 23 symptomatic patients with ICA occlusion and 68 control subjects. Our results show that in patients the middle cerebral artery flow territory ipsilateral to the occluded ICA is dependent on the posterior circulation, whereas the ipsilateral anterior cerebral artery flow territory is supplied by the contralateral ICA.