Table 4.
Average overlap ratios of computer automated segmentation relative to the radiologist’s first manual segmentation. The statistical significance of the difference between FCM-based initial segmentation and the LS(FCM) was evaluated by the paired t test. Likewise, the statistical significance of the difference between LS(FCM) and LS(k means) was evaluated by the paired t test.
| Segmentation method | Overlap ratio VOR1 | Overlap ratio VOR2 | ||
|---|---|---|---|---|
| Prechemo. | Postchemo. | Prechemo. | Postchemo. | |
| Initial segmentation (FCM) | 0.72±0.16 | 0.44±0.21 | 0.64±0.14 | 0.38±0.20 |
| LS(FCM) | 0.81±0.13 | 0.71±0.22 | 0.69±0.10 | 0.47±0.20 |
| LS(k means) | 0.79±0.13 | 0.58±0.26 | 0.68±0.10 | 0.41±0.20 |
| p value between LS(FCM) and FCM | 4.3×10−7 | 1.0×10−6 | 6.1×10−3 | 1.8×10−3 |
| p value between LS(FCM) and LS(k means) | 3.3×10−3 | 1.3×10−3 | 0.51 | 0.014 |