Table 1.
Summary of method performance averaged over the 19 subjects of the full projection dataset as quantified by the image quality measures of TIS at the diaphragm and bronchus intermedius and noise of three ROIs (air, aorta, and soft tissue). Percentage metrics presented represent the relative percentage of TIS recovered across the three evaluated interfaces relative to the initial 4D‐CBCT reconstruction
| Reference frame and method | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Average of 4D‐CBCT | Fixed frame (ff); registration‐only | Fixed frame (FF); MoCo recon. | Mean frame (MF); registration‐only | Mean frame (MF); MoCo recon. | ||||||
| Mean (%) | Std. Dev. (%) | Mean (%) | Std. Dev. (%) | Mean (%) | Std. Dev. (%) | Mean (%) | Std. Dev. (%) | Mean (%) | Std. Dev. (%) | |
| TIS recovery | ||||||||||
| Diaphragm | 95.7 | (39.0) | 98.5 | (20.0) | 98.4 | (19.9) | 122 | (43.8) | 121 | (43.4) |
| Bronchus intermedius | 82.5 | (20.7) | 95.4 | (9.24) | 94.9 | (10.3) | 94.3 | (20.4) | 93.8 | (21.8) |
| ROI noise reduction | ||||||||||
| Ambient air | 64.4 | (9.95) | 64.1 | (8.86) | 7.6 | (11.2) | 62.7 | (9.98) | 67.6 | (11.4) |
| Aorta | 59.5 | (6.82) | 57.0 | (5.86) | 57.3 | 5.44) | 59.0 | (5.55) | 58.2 | (5.55) |
| Soft tissue | 52.3 | (11.7) | 42.7 | (8.41) | 43.5 | (9.42) | 40.5 | (8.64) | 41.7 | (8.95) |