Figure 1.

Illustration of atrophy simulation in two subjects. A representative axial slice at the center of the atrophy sphere is shown with and without simulated atrophy. Red circles are used to show the location of the atrophy only. The circle radius has no relationship to the radius of the atrophy sphere or atrophy rate. All images are in their native space. a,e,c,g: Respectively, the original raw and WM images without change from two subjects. b,f,d,h: Respectively, the raw and WM images with 5% simulated atrophy in the left midbrain. Atrophy can be seen at the edge of segmented WM images while topologies of deformed structures were preserved (f,h).