Figure 3.
Effect of 4D-PET on sphere-to-background ratio. The sphere-to-background ratios of the nongated PET (blue), helical AC-gated PET (red), and PM- (green) gated PET analyzed by max (A) and peak (B) versus surrogate mean. Error bars on the PM- and helical AC-gated images represent the standard deviation of the 6 bins.