Table VI.
Comparison of measurement unit mean ratios and correlation coefficients from 24 and 35 cm DSV phantoms for 0.35 T ViewRay MRIdian MRI-Linac measurements for gantry angles from 0° to 330° in 30° increments.
| Comparison | DSV | With gradient shimming |
Without gradient shimming |
||||
|---|---|---|---|---|---|---|---|
| Mean ratio (SD) | Pearson coefficient | P value | Mean ratio (SD) | Pearson coefficient | P value | ||
| pk-pk vs VRMS | 24 | 7.702 (1.093) | −0.638 | 0.023 | 5.871 (0.928) | 0.946 | <<0.001 |
| 35 | 10.979 (2.347) | −0.004 | 0.991 | 7.397 (1.474) | 0.692 | 0.010 | |
| pk-pk vs FWHM | 24 | 3.288 (0.901) | −0.371 | 0.230 | 1.809 (0.867) | 0.822 | <0.001 |
| 35 | 3.753 (0.704) | 0.360 | 0.246 | 2.092 (0.761) | 0.541 | 0.065 | |
| VRMS vs FWHM | 24 | 0.424 (0.090) | 0.707 | 0.008 | 0.304 (0.135) | 0.931 | <<0.001 |
| 35 | 0.345 (0.033) | 0.560 | 0.054 | 0.279 (0.071) | 0.910 | <<0.001 | |
FWHM: Full width half maximum, pk-pk: phase map peak-to-peak, VRMS: phase map volume root mean square.