The authors compared high-signal-intensity flow-related artifacts present with a conventional two-dimensional (2D) fluid-attenuated inversion recovery (FLAIR) sequence with those seen with a single-slab, three-dimensional (3D) FLAIR sequence. Four readers graded the subarachnoid space and intraventricular artifacts, the pulsation artifacts, and the conspicuity of cranial nerves in the posterior fossa. For all comparisons, differences between 2D and 3D images were highly statistically significant, with 3D imaging being superior in all cases.