Fig. 6—

Imaging of intracranial arteries.

A, 38-year-old healthy individual who volunteered to undergo 7-T MRI of brain. Three-dimensional maximum-intensity projection (MIP) image from 3D TOF MRA (slice thickness, 0.25 mm; matrix, 640 × 500; FOV, 180 mm; interslice distance, 18.75%; voxel size, 0.1 × 0.1 × 0.3 mm; acquisition time, 19 minutes; TR/TE, 26/7; acceleration factor, GRAPPA 2; interpolation on) shows excellent detail of intracranial arteries. Incidentally detected artery of Percheron (turquoise arrow) arises from right posterior cerebral artery P1 segment and exhibits early bifurcation to right and left thalamic perforators. Medial and lateral lenticulostriate arteries (red arrows) can be followed to thinner distal branches in basal ganglia. Cavernous internal carotid arteries (white arrows) are not clearly visible owing to artifact near skull base.

B, 38-year-old woman referred for brain tumor follow-up. Three-dimensional MIP image reconstructed from precontrast MP-RAGE MRA shows normal delineation of cavernous internal carotid arteries (arrows). This method can be used in conjunction with 3D TOF MRA for complete visualization of intracranial arterial vasculature.