Fig. 2.

Traffic-light heatmap of segmentation geometric and CT number agreement for the (a) 2D and (b) 3D sCT. Columns show DSC, HD95, and mean CT number error (ME) evaluated within the sCT-defined mask (self-mask) and the rCT-defined mask (common-mask). ME values are reported as absolute CT number difference with relative deviation in parentheses. Color thresholds are: DSC green ≥0.8, yellow 0.6–0.8, red <0.6; HD95 green ≤2.0 mm, yellow 2.0–5.0 mm, red >5.0 mm; Bone ME green |ME| ≤ 100 HU, yellow 100–400 HU, red >400 HU; Soft tissue green |ME| ≤ 10 HU, yellow 10–20 HU, red >20 HU. See main text for mask definitions and threshold rationale. sCT = synthetic computed tomography; rCT = reference CT; DSC = Dice similarity coefficient; HD95 = 95th percentile Hausdorff distance; ME = mean error; HU = Hounsfield units. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)