Table 2 Monitor units (MUs) and structure doses in the form of a ratio normalized to a reference value from the case of a 2-mm grid size and 2° angular increment, when different plan parameter sets (grid sizes of 2 mm, 3 mm, and 4 mm, and angular increments of 2°, 4°, 6°, and 10°) were used in the thorax phantom for the cases of spherical targets [S 2 (2-cm diameter), S 3 (3-cm diameter), and S 4 (4-cm diameter)]
Grid size (mm) | Angular increment (°) | MU | Structures | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
PTV (Dmean) | Heart (Dmax) | Normal lung (D1000cc) | Spinal cord (Dmax) | |||||||||||
V9,0 | V9,5 | V9,10 | V9,20 | V11,0 | V11,5 | V11,10 | V11,20 | |||||||
S2 | 2 | 2 | 1.00 (1638)a | 1.00 (50.37)b | 1.00 (13.60) | 1.00 (7.40) | 1.00 (6.92) | 1.00 (7.19) | 1.00 (7.44) | 1.00 (7.48) | 1.00 (5.57) | 1.00 (5.77) | 1.00 (6.09) | 1.00 (6.34) |
4 | 0.99 | 1.00 | 1.00 | 1.12 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 0.99 | 1.00 | ||
6 | 0.99 | 1.00 | 1.00 | 1.12 | 1.01 | 1.01 | 1.01 | 1.02 | 1.03 | 1.00 | 1.00 | 1.02 | ||
10 | 0.99 | 1.00 | 1.00 | 1.11 | 1.05 | 1.07 | 1.00 | 1.04 | 1.09 | 1.06 | 1.07 | 1.06 | ||
3 | 2 | 1.01 | 1.00 | 1.01 | 1.00 | 1.01 | 1.00 | 1.01 | 1.01 | 1.01 | 1.01 | 1.00 | 1.00 | |
4 | 1.00 | 1.00 | 1.01 | 1.12 | 1.00 | 1.01 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | ||
6 | 1.00 | 1.00 | 1.00 | 1.12 | 1.01 | 1.01 | 1.01 | 1.02 | 1.03 | 1.01 | 1.00 | 1.01 | ||
10 | 1.00 | 1.00 | 1.00 | 1.12 | 1.05 | 1.04 | 1.00 | 1.03 | 1.10 | 1.06 | 1.07 | 1.06 | ||
4 | 2 | 1.03 | 1.01 | 1.04 | 1.05 | 1.02 | 1.03 | 1.02 | 1.03 | 1.03 | 1.03 | 1.03 | 1.02 | |
4 | 1.01 | 1.00 | 1.02 | 1.16 | 1.01 | 1.01 | 1.01 | 1.01 | 1.02 | 1.01 | 1.01 | 1.00 | ||
6 | 1.01 | 1.00 | 1.03 | 1.16 | 1.01 | 1.03 | 1.01 | 1.01 | 1.02 | 1.01 | 1.01 | 1.02 | ||
10 | 1.01 | 1.00 | 1.04 | 1.16 | 1.05 | 1.06 | 1.01 | 1.05 | 1.10 | 1.07 | 1.08 | 1.07 | ||
S3 | 2 | 2 | 1.00 (1518) | 1.00 (46.41) | 1.00 (18.09) | 1.00 (1.76) | 1.00 (9.18) | 1.00 (9.65) | 1.00 (10.03) | 1.00 (10.10) | 1.00 (7.31) | 1.00 (7.61) | 1.00 (8.12) | 1.00 (8.45) |
4 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | ||
6 | 1.00 | 1.00 | 1.00 | 0.99 | 1.01 | 1.00 | 1.01 | 1.01 | 1.01 | 1.02 | 1.01 | 0.99 | ||
10 | 1.00 | 1.00 | 1.00 | 0.99 | 1.01 | 1.00 | 1.02 | 0.99 | 1.03 | 1.09 | 1.01 | 1.05 | ||
3 | 2 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |
4 | 1.00 | 1.00 | 1.00 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 1.01 | 1.01 | 1.00 | ||
6 | 1.00 | 1.00 | 1.00 | 0.99 | 1.01 | 1.00 | 1.00 | 1.01 | 1.01 | 1.02 | 1.01 | 0.99 | ||
10 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 0.99 | 1.03 | 1.09 | 1.01 | 1.04 | ||
4 | 2 | 1.01 | 1.00 | 1.01 | 1.02 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |
4 | 1.01 | 1.00 | 1.02 | 1.03 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | ||
6 | 1.01 | 1.00 | 1.01 | 1.02 | 1.01 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.01 | 1.00 | ||
10 | 1.01 | 1.00 | 1.01 | 1.02 | 1.00 | 1.00 | 1.01 | 0.99 | 1.02 | 1.08 | 1.01 | 1.04 | ||
S4 | 2 | 2 | 1.00 (1454) | 1.00 (45.00) | 1.00 (23.03) | 1.00 (3.13) | 1.00 (11.42) | 1.00 (11.96) | 1.00 (12.37) | 1.00 (12.50) | 1.00 (9.00) | 1.00 (9.37) | 1.00 (9.98) | 1.00 (10.38) |
4 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | ||
6 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.03 | 1.00 | 0.99 | 1.01 | ||
10 | 1.00 | 1.00 | 1.00 | 1.01 | 1.02 | 0.99 | 1.01 | 1.02 | 0.98 | 1.04 | 0.99 | 0.99 | ||
3 | 2 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |
4 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | ||
6 | 1.00 | 1.00 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 0.99 | 0.99 | 1.01 | ||
10 | 1.00 | 1.00 | 1.00 | 1.00 | 1.01 | 0.99 | 1.01 | 1.02 | 0.98 | 1.03 | 0.99 | 0.99 | ||
4 | 2 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |
4 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | ||
6 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | ||
10 | 1.00 | 1.00 | 1.01 | 1.01 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | ||