Table 2:

Observed R1 enhancement of the pixels of the ROI line drawn by a neuroradiologist to encapsulate the enhancing tumor, as a percentage of all values above dR1 = 0.2 seconds−1, the mean dR1, and the mean dR1 of all values of >0.2 seconds−1a

dR1 >0.2 s−1 (%)Mean dR1 (s−1)Mean dR1 (>0.2 s−1 only) (s−1)
SyntheticSubtractionSyntheticSubtractionSyntheticSubtraction
On ROI line35.8 ± 14.350.3 ± 10.20.19 ± 0.090.27 ± 0.080.48 ± 0.120.46 ± 0.11
+ 1 mm8.0 ± 5.817.4 ± 9.00.03 ± 0.020.08 ± 0.050.35 ± 0.080.37 ± 0.12
+ 2 mm2.3 ± 1.58.6 ± 4.90.01 ± 0.010.04 ± 0.040.32 ± 0.150.37 ± 0.17

  • a Results are listed for the R1 difference generated by synthesizing the R1 difference map and subtraction of the pre- and post-GBCA R1 maps. Two more ROI lines were created at 1- and 2-mm outward to analyze the results if a larger margin around the enhancing tumor had been drawn.