Angiography of the Cerebral Vasculature with Arterial Spin Labeling 1

Purpose: To demonstrate an arterial spin-labeling (ASL) magnetic resonance (MR) angiographic technique that covers the entire cerebral vasculature and yields transparent-background, time-resolved hemodynamic, and vessel-specifi c informa-tion similar to that obtained with x-ray digital subtraction angiography (DSA) without the use of exogenous contrast agents. Materials and Methods: Prior institutional review board approval and written in-formed consent were obtained for this HIPAA-compliant study in which 12 healthy volunteers (fi ve women, seven men; age range, 21—62 years; average age, 28 years) underwent imaging. An ASL technique in which variable labeling durations are used to acquire hemodynamic in