title: Pseudo-continuous arterial spin labeling at 7 T for human brain: estimation and correction for off-resonance effects using a Prescan.
abstract: Pseudo-continuous arterial spin labeling (ASL) can provide best signal-to-noise ratio efficiency with a sufficiently long tag at high fields such as 7 T, but it is very sensitive to off-resonance fields at the tagging location. Here, a robust Prescan procedure is demonstrated to estimate the pseudo-continuous ASL radiofrequency phase and gradients parameters required to compensate the off-resonance effects at each vessel location. The Prescan is completed in 1-2 min and is based on acquisition of label/control pair-wise ASL data as a function of the radiofrequency phase increment applied to the pseudo-continuous ASL train. It is shown that this approach can be used to acquire high quality whole-brain pseudo-continuous ASL perfusion data of the human brain at 7 T.
authors.affiliation: Functional MRI Facility, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, USA. wmluh@nih.gov
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Luh
authors.forename: S Lalith
authors.initials: SL
authors.lastname: Talagala
authors.forename: Tie-Qiang
authors.initials: TQ
authors.lastname: Li
authors.forename: Peter A
authors.initials: PA
authors.lastname: Bandettini
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D002536:Cerebral Arteries / Q000033:anatomy & histology / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013113:Spin Labels
chemical_list: D013113:Spin Labels