Table 4 Image quality comparison for SS and CTM acquisition modes. The sphere-to-background ratio is 4:1 and 8:1. For the 4:1 ratio, the SS acquisition followed the CTM acquisition subsequently. For the 8:1 ratio, the CTM acquisition followed the SS subsequently
Sphere diameter (mm) | Sphere-to-background ration = 4:1 | Sphere-to-background ration = 8:1 | ||||||
|---|---|---|---|---|---|---|---|---|
Contrast recovery (%) | Background variability (%) | Contrast recovery (%) | Background variability (%) | |||||
SS | CTM | SS | CTM | SS | CTM | SS | CTM | |
10 | 26.0 | 28.3 | 5.3 | 6.9 | 43.7 | 41.9 | 4.9 | 6.3 |
13 | 44.8 | 47.9 | 4.6 | 6.8 | 59.8 | 63.1 | 4.1 | 5.4 |
17 | 61.9 | 58.4 | 3.9 | 5.6 | 66.6 | 68.1 | 3.3 | 4.4 |
22 | 69.2 | 70.8 | 3.1 | 4.7 | 75.5 | 76.6 | 2.8 | 3.6 |
28 | 68.8 | 67.0 | 2.5 | 3.8 | 70.7 | 71.3 | 2.5 | 3.0 |
37 | 76.5 | 76.9 | 2.2 | 2.9 | 77.5 | 77.7 | 2.1 | 2.4 |
Lung residual (%) (σ) | 12.2 (0.9) | 12.3 (1.0) | 12.3 (0.9) | 12.1 (0.6) | ||||