Table 1.
Dose-volume indices between CBCT and CT
| Parameter | CBCT, ± SEM | CT, ± SEM | t | P |
|---|---|---|---|---|
| V5Gy-Ra |
47.7 ± 16.4% |
49.0 ± 16.0% |
1.5 |
0.17 |
| V10Gy-R |
18.9 ± 11.7% |
17.4 ± 11.8% |
2.3 |
0.03 |
| V15Gy-R |
14.4 ± 10.2% |
12.8 ± 10.4% |
2.3 |
0.02 |
| V20Gy-R |
10.5 ± 9.0% |
9.0 ± 8.9% |
2.3 |
0.04 |
| V25Gy-R |
6.6 ± 2.8% |
4.5 ± 2.3% |
3.6 |
0.01 |
| V30Gy-R |
4.2 ± 2.2% |
2.5 ± 1.6% |
3.7 |
0.01 |
| V35Gy-R |
3.2 ± 1.8% |
1.7 ± 1.3% |
3.9 |
0.01 |
| V5Gy-Ab |
333.0 ± 78.4 cm3 |
282.0 ± 61.7 cm3 |
7.9 |
0.0001 |
| V10Gy-A |
133.0 ± 68.6 cm3 |
101.0 ± 59.0 cm3 |
6.8 |
0.0001 |
| V15Gy-A |
102.0 ± 62.6 cm3 |
74.6 ± 53.7 cm3 |
6.2 |
0.0001 |
| V20Gy-A |
74.0 ± 55.8 cm3 |
52.5 ± 46.4 cm3 |
4.8 |
0.0001 |
| V25Gy-A |
46.0 ± 16.9 cm3 |
27.0 ± 12.0 cm3 |
6.2 |
0.0001 |
| V30Gy-A |
30.0 ± 14.4 cm3 |
15.0 ± 8.7 cm3 |
5.5 |
0.0001 |
| V35Gy-A |
24.0 ± 12.0 cm3 |
10.0 ± 7.0 cm3 |
5.5 |
0.0001 |
| D50cm3c |
19.9 ± 7.7 Gy |
17.1 ± 6.3 Gy |
4.5 |
0.0001 |
| D100cm3 |
15.3 ± 6.2 Gy |
12.8 ± 5.7 Gy |
3.6 |
0.003 |
| D150cm3 |
11.8 ± 5.5 Gy |
9.2 ± 3.4 Gy |
3.6 |
0.003 |
| D200cm3 |
8.2 ± 2.0 Gy |
6.8 ± 1.5 Gy |
6.2 |
0.0001 |
| D250cm3 |
6.4 ± 1.7 Gy |
5.2 ± 2.0 Gy |
6.5 |
0.0001 |
| Dmean |
7.0 ± 2.8 Gy |
6.5 ± 2.4 Gy |
3.0 |
0.009 |
| Dmax | 45.7 ± 13.1 Gy | 45.1 ± 13.5 Gy | 2.9 | 0.009 |
a). V5Gy-R means the heart relative volume in the 5Gy region, V10Gy-R, V15Gy-R, V20Gy-R, V25Gy-R, V30Gy-R, and V35Gy-R are of the same mean;
b). V5Gy-A means the heart absolute volume in the 5Gy region, V10Gy-A, V15Gy-A, V20Gy-A, V25Gy-A, V30Gy-A, and V35Gy-A are of the same mean;
c). D50cm3 means the exposure dose in the 50 cm3, D100cm3, D150cm3, D200cm3, and D250cm3 are of the same mean.