Table 3.
Statistical comparison of the tested linacs using the RMSD of measured data in CW and CCW directions, and using 0 and 90 degree collimators
| CW vs. CCW | Col 0 vs. Col90 | |||
|---|---|---|---|---|
| Average RMSD | Maximum RMSD | Maximum RMSD | ||
| EPID Sag (mm) | Cross-plane | 0.07 | 0.44 (L#7) | 0.00 (L#12) |
| In-plane | 0.22 | 1.61 (L#7) | 0.01 (L#7) | |
| Gantry Sag (mm) | Cross-plane | 0.11 | 0.26 (L#6) | 0.07 (L#2) |
| In-plane | 0.04 | 0.12 (L#8) | 0.02 (L#9) | |
| SDD (mm) | 0.60 | 0.81 (L#7) | 0.00 (L#7) | |
| EPID and Collimator Skew (degrees) | 0.16 | 1.62 (L#7) | 0.01 (L#7) | |
| EPID Tilt (degrees) | Cross-plane | 0.06 | 0.07 (L#7) | 0.01 (L#7) |
| In-plane | 0.01 | 0.08 (L#7) | 0.01 (L#12) | |
| MLC Sag (mm) | Left | 0.19 | 0.30 (L#9) | 0.38 (L#7) |
| Right | 0.21 | 0.54 (L#7) | 0.38 (L#7) | |
| Gun | 0.07 | 0.18 (L#7) | 0.41 (L#3) | |
| Target | 0.06 | 0.19 (L#3) | 0.47 (L#3) | |
Values are in mm except for the EPID tilt and skew which are given in degrees. The largest deviations are listed and their corresponding linac numbers are given in parentheses.