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Implementation of quantitative perfusion imaging using pulsed arterial spin labeling at ultra‐high field

This study compares the implementation of the STAR and FAIR pulsed arterial spin labeling (PASL) schemes to form quantitative perfusion maps at ultra‐high field, 7 Tesla (T), and high field, 3T. Phantom experiments were performed to compare the inversion efficiency and profile of the labeling pulses at 7T and 3T and to optimize in‐plane saturation techniques. The perfusion weighted (PW) signal was measured at a range of postlabeling delay times and quantitative perfusion maps were calculated on a voxel‐by‐voxel basis. An increase in PW signal was found with field strength, and together with the increased signal‐to‐noise ratio, this led to improved image signal‐to‐noise and quality of fit of perfusion maps at 7T. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.