Table 2.
Mean Dice’s coefficient and Hausdorff distance values for multiple atlas libraries of normal organs
| Size of atlas library | |||
|---|---|---|---|
| 20 | 40 | 60 | |
| Femur | |||
| DC (95% CI) | 0.92 (0.90–0.95) | 0.94 (0.93–0.96) | 0.95 (0.94–0.96) |
| p-value | ref. | 0.289 | 0.335 (0.335++) |
| HD (95% CI) | 10.0 (7.8–15.4) | 8.4 (6.0–10.8) | 5.6 (4.0–7.4) |
| p-value | ref. | 0.285 | 0.046 (0.024++) |
| Femur-sm | |||
| DC (95% CI) | 0.93 (0.91–0.94) | 0.94 (0.93–0.95) | 0.95 (0.93–0.96) |
| p-value | ref. | 0.298 | 0.304 (0.139++) |
| p-value* | 0.341 | 0.798 | 0.782 |
| HD (95% CI) | 9.7 (7.2–12.2) | 8.5 (6.3–10.8) | 5.7 (4.5–7.1) |
| p-value | ref. | 0.466 | 0.023 (0.013++) |
| p-value* | 0.162 | 0.869 | 0.794 |
| ABAS-Bladder | |||
| DC (95% CI) | 0.57 (0.47–0.65) | 0.53 (0.45–0.62) | 0.54 (0.44–0.63) |
| p-value | ref. | 0.454 | 0.803 (0.096++) |
| HD (95% CI) | 44.6 (31.0–66.7) | 59.1 (39.1–82.1) | 60.2 (40.2–84.0) |
| p-value | ref. | 0.121 | 0.883 (0.024++) |
| ABASc-Bladder | |||
| DC (95% CI) | 0.78 (0.73–0.83) | 0.85 (0.81–0.88) | 0.84 (0.82–0.87) |
| p-value | ref. | 0.001 | 0.006 (0.398++) |
| p-value** | 0.051 | < 0.001 | 0.001 |
| HD (95% CI) | 13.2 (11.8–14.6) | 11.3 (10.6–12.0) | 11.9 (11.1–12.9) |
| p-value | ref. | 0.031 | 0.085 (0.282++) |
| p-value** | 0.196 | 0.020 | 0.007 |
Abbreviations ABAS atlas-based auto-segmentation alone, ABASc manually corrected ABAS, sm simultaneous, DC Dice’s coefficient, HD Hausdorff distance, CI confidence interval
* Comparison between Femur and Femur-sm
** Comparison between ABAS and ABASc
++Comparison between atlas sets sized 40 and 60