Table 2.
Mean and standard deviation (in parenthesis) of Dice similarity coefficients and Hausdorff distances for the five structures*.
| Liver | Stomach | Duodenum | Kidney (Rt) | Kidney (Lt) | |||
|---|---|---|---|---|---|---|---|
| Dice similarity coefficient | U-Net-based | 0.959 (0.018) | 0.813 (0.137) | 0.595 (0.186) | 0.900 (0.174) | 0.911 (0.159) | |
| Atlas-based | 0.808 (0.116) | 0.431 (0.188) | 0.153 (0.113) | 0.742 (0.027) | 0.700 (0.219) | ||
| Inter-observer | 0.963 (0.006) | 0.903 (0.048) | 0.732 (0.052) | 0.938 (0.184) | 0.912 (0.105) | ||
| P-value | U-Net vs. Atlas | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |
| U-Net vs. Inter-observer | 0.330 | 0.031 | 0.006 | 0.622 | 0.694 | ||
| Hausdorff distance | U-Net-based | 8.926 (6.298) | 19.890 (19.286) | 23.423 (20.088) | 4.780 (2.735) | 5.789 (4.278) | |
| Atlas-based | 34.932 (18.619) | 41.498 (23.814) | 44.165 (14.096) | 16.554 (8.995) | 18.093 (12.228) | ||
| Inter-observer | 7.261 (2.476) | 12.106 (9.363) | 30.264 (12.692) | 4.201 (1.299) | 6.426 (7.522) | ||
| P-value | U-Net vs. Atlas | 0.000 | 0.007 | 0.003 | 0.000 | 0.000 | |
| U-Net vs. Inter-observer | 0.430 | 0.090 | 0.083 | 0.694 | 0.738 | ||
| Mean surface distance | U-Net-based | 0.714 (0.301) | 3.034 (5.687) | 2.796 (1.904) | 1.104 (1.108) | 0.918 (1.276) | |
| Atlas-based | 4.114 (2.929) | 8.115 (4.739) | 13.661 (8.583) | 2.989 (2.368) | 3.680 (3.791) | ||
| Inter-observer | 0.460 (0.093) | 0.743 (0.424) | 2.944 (1.725) | 0.665 (0.438) | 0.781 (1.193) | ||
| P-value | U-Net vs. Atlas | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |
| U-Net vs. Inter-observer | 0.000 | 0.001 | 0.679 | 0.030 | 0.143 | ||
*Produced from U-Net based method, Atlas-based method, and inter-observer, relative to the previously drawn ground-truth contours.