Fig. 4

Manual (expert) segmentation overlaid with automated segmentation output (white areas) of the caudate nucleus and putamen from 1.5T (upper row) and 3T (lower row) 3D T1-weighted MRI scans. Images are from a 51 year-old woman with multiple sclerosis and moderate physical disability. The total DGM volume was 28.4 ml at1.5T and 29.3 ml at 3T. For illustrative purposes, the ground truth contours are shown in both red and yellow colors. Automated segmentation was performed by the fully automated FSL-FIRST pipeline. The 3T automated output typically provided a larger and more accurate contour than 1.5T. At 1.5T, the interface between the caudate and the anterior and medial aspects of the ventricular CSF is underestimated vs. 3T. The interface between the putamen and the adjacent (lateral) white matter appears to be larger and more accurate at 3T