Table 1.
Patient demographics.
Fig 1.
Synthetic images created from the quantitative scan.
An example of synthetic T1GdWI (top left), proton density map (top right), R1 map (bottom left), and R2 map (bottom right) in a 68-year-old male with a glioblastoma.
Fig 2.
ROIs delineating the peritumoral edema and the contrast-enhancing part of the tumor.
A ROI was placed in the peritumoral edema of the synthetic T2WI. The edema ROI was then applied in the qMRI volumes to obtain the quantitative values of R1, R2, and proton density. The contrast-enhancing part of the tumor was manually delineated in the synthetic T1GdWI and subtracted to avoid overlap with the edema ROI.
Fig 3.
Color histograms of R1, R2, proton density and rCBV.
Color histograms of R1, R2, proton density, and rCBV in the peritumoral edema in relation to distance from the contrast-enhancing part of the tumors of all patients. The thick black lines represent the regression line given by the mixed linear models, with the slope presented as beta value in the figure. The thin black lines represent the confidence intervals. For R1, R2, and rCBV, there is a decrease in values with increasing distance from the contrast-enhancing part of the tumor. Proton density has a slight decrease with increasing distance. There is a significant increase in the gradient of the relaxation values after contrast agent injection (p < 0.001). The pattern of relaxation values is more heterogeneous closer to the contrast-enhancing part of the tumor.
Fig 4.
An example of synthetic MRI in one of the patients.
Fig 4 is an example of the synthetic and quantitative images of a 76-year-old man with glioblastoma. The top row shows the synthetic images: (A) native T1WI, (B) post-GD T1WI, (C) T2WI post-GD. The center row shows the R1 maps: (D) native R1 map, (E) post-GD R1 map, (F) difference-map of post-GD R1 minus native R1. The bottom row shows the R2 maps: (G) native R2 map, (H) post-GD R2 map, (I) difference-map of post-GD R2 minus native R2. In (F) and (I), a white line is indicated, along which native (dotted line) and post-GD (solid line) data are plotted regarding R1 (top) and R2 (bottom) as a function of the distance to tumor, as shown in the diagrams. The zero distance point is indicated by the small perpendicular line in (F) and (I).
Table 2.
qMRI values of ROIs: Group mean and SD (N = 19).
Table 3.
Mixed linear model with qMRI values as dependent variable and distance to tumor as fixed effect.