Figure 3.

Changes in the T₂-MD multidimensional MR signature induced by confirmed astrogliosis. Maps of 2D spectra of subvoxel T₂-MD values reconstructed on a 16 × 16 grid of a representative (A) control (Case 7) and (B) injured (Case 10) subjects, along with their respective GFAP histological image (top left of each panel). (C) Magnified spectral region from the control case shows the clear separation of white (yellow frame) and grey (teal frame) matter according to their diffusion and T₂ values. (D) The same magnified spectral region as in C from the injured case shows that while the WM and GM spectral information content is still clearly separable (yellow and teal frames, respectively), distinct spectral components can be seen on the grey–white matter interface (purple frame), which is qualitatively similar to the GFAP staining pattern of the sample. (E) T₂-MD spectra averaged across all subjects in WM, GM and GFAP-positive spatial regions of interest (left to right) and a superposition of the average spectra from the three regions of interest. It should be noted that the peak in normal-appearing WM was forced to align between subjects, but not in GM or in injured tissue.