Figure 4.

EV maps and short-track TDI maps, magnified view at 3 brainstem levels (rostral medulla, middle pons, and rostral midbrain) in an 8-year-old child. Upper row: EV images. Lower row: stDEC-TDI images. Conventional color scheme: blue (inferior–superior), green (anteroposterior), and red (left–right). First column (A,D): at the bulbar level, the corticospinal tract is on the anterior surface of the pyramids (arrowhead), adjacent to the inferior olivary nucleus (asterisk). In the EV map, non-WM voxels show and “blur” the corticospinal tract, making it more difficult to distinguish. Second column (B,E): at mid-pons level, the pyramidal tract (arrowhead) is clearly separated from the transverse pontocerebellar fibers (thin arrow) and ascending pathways (thick arrow). Note the dentate nuclei (empty arrow), almost not recognizable in the EV map. Third column (C,F): at rostral midbrain, the central tegmental tract (arrow) is located posteriorly to the red nuclei (arrowhead). Note the optic tracts colored in green (thin arrow). The smaller voxel size of the stDEC-TDI maps allows to visualize all the structures correctly even at a zoomed level, while the EV maps at the same level of magnification appear blurred and with a stair-stepped effect.