Fig. 15.

Positioning of the selective labeling planes for territorial ASL based on an MR angiogram of the circle of Willis for the right internal carotid artery (ICA, red box) and the basilar artery (blue box). The labeling plane for the left ICA is not shown, as this vessel was occluded and no signal was obtained. b Colour territorial perfusion maps showing the distribution of brain tissue perfused by the intracranial arteries labeled in (a). The anterior and middle cerebral artery territories in both hemispheres are supplied by the right ICA in this patient with left ICA occlusion (in red). The medial occipital and parietal lobes are supplied by the basilar artery (in blue)