Does MS grey matter pathology progress faster in regions with more damage in connected white matter?

Three measures for WM damage will be assessed, i.e. lesion volume, lesion fractional anisotropy (FA) and NAWM FA, from which a composite WM damage score will be computed. High versus low WM damage scores will then be compared to the atrophy rates in the GM, based on subcortical volume and cortical thickness measures. From this, we can compare atrophy rates of each GM structure from baseline to year 1 between the group of patients with higher damage in the WM tracts connected to that GM structure on the one hand, and the group of patients with lower damage in those WM tracts on the other.<br>
Similar calculations will be performed between year 1 and year 2 in order to determine whether a larger increase of WM damage over the first study year is predictive of faster subsequent GM atrophy in the second year.