Table 2:

Median number (volume) of analyzed voxels per patient in each tissue type for each quantitative MR imaging measurea

Tissue TypeTechnique
NAWM117.5 (2.8 mL)624 (2.5 mL)660 (2.6 mL)660 (2.6 mL)
DAWM53 (1.3 mL)327 (1.3 mL)283 (1.1 mL)200 (0.8 mL)
Focal WM lesions19.5 (0.5 mL)117 (0.5 mL)123.5 (0.5 mL)80.5 (0.3 mL)
  • a Median values are given for the entire group of patients in this study. A more detailed subdivision by anatomic region and disease type is provided in Table 3. The size of each region of interest was defined as the total number of voxels included in the ROI, after warping it to the corresponding quantitative MR imaging maps as described in the text. The corresponding ROI volume was calculated by multiplying the number of voxels by the appropriate voxel volume, which was 4 mm3 for the T1 and MTR maps, and 24 mm3 for the ADC and FA maps. The column headed “Pd” gives the values for the original ROIs as drawn on the Pd-weighted images.