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Table 1: 
Comparison of CTP with MRP imaging
CTPMRP
CTP advantages
    Linear relation of signal changes with contrast concentration; quantitative maps    Nonlinear relation of signal changes with gadolinium concentration; nonquantitative maps
    Higher spatial resolution    Lower spatial resolution
    More readily available    Not as readily available
MRP advantages
    Ionizing radiation    No ionizing radiation
    Limited z-direction coverage    Whole-brain coverage
    Iodinated contrast–related concerns    Gadolinium contrast concerns (NSF)
    Complex postprocessing    Less labor-intensive postprocessing
  • Note:—NSF indicates nephrogenic systemic fibrosis; CTP, CT perfusion; MRP, MR perfusion.