1Radiology,
  Athinoula A. Martinos Center for Biomedical Imaging / Massachusetts General
  Hospital, Charlestown, MA, United States; 2Neuro-oncology, Brigham
  and Women's Hospital / Harvard Medical School, Boston, MA, United States; 3Neurology,
  Massachusetts General Hospital / Harvard Medical School, Boston, MA, United
  States
We assessed the voxel-wise repeatability of ADC values in patients with newly diagnosed glioblastoma in relation to functional diffusion mapping technique. Although the intra-class correlation coefficients are relatively high, the variability of the tumor values exceeds the thresholds for stable voxels, as proposed by functional diffusion mapping, suggesting the absolute thresholding be re-evaluated.