Three-dimensional renderings (not to scale) of the one- (left) and ten-year-old (right) male phantoms, visualized within the external beam planning module of the Varian Eclipse TPS. Major organ and skeletal contours are shown. The voxel resolutions (x,y,z) are (0.0663 cm, 0.0663 cm, 0.14 cm) and (0.099 cm, 0.099 cm, 0.2425 cm) for the one- and ten-year-old, respectively.