Table 2.
Magnetic Resonance Imaging Isocenter Displacement From the Virtual Isocenter Measured With the DQA and MagPhan.a
| Gantry Angle | DQA | MagPhan | ||||
|---|---|---|---|---|---|---|
| Ave. ΔX± 1SD (mm) | Ave. ΔY± 1SD (mm) | Ave. ΔZ± 1SD (mm) | Ave. ΔX± 1SD (mm) | Ave. ΔY± 1SD (mm) | Ave. ΔZ± 1SD (mm) | |
| 0° | 0.57 ± 0.12 | 0.63 ± 0.12 | −0.20 ± 0.0 | 0.57 ± 0.06 | 0.50 ± 0.0 | −0.37 ± 0.06 |
| 270° | 0.43 ± 0.12 | 0.50 ± 0.0 | 0.87 ± 0.06 | 0.37 ± 0.06 | 0.50 ± 0.0 | 0.53 ± 0.06 |
| 180° | −0.70 ± 0.0 | 0.50 ± 0.0 | 0.70 ± 0.10 | −0.80 ± 0.0 | 0.57 ± 0.06 | 0.30 ± 0.0 |
| 90° | −0.57 ± 0.12 | 0.47 ± 0.06 | −0.27 ± 0.06 | −0.50 ± 0.0 | 0.50 ± 0.0 | −0.70 ± 0.0 |
| Ave | −0.07 | 0.53 | 0.28 | −0.09 | 0.52 | −0.06 |
| Max-Min | 1.27 | 0.17 | 1.13 | 1.37 | 0.07 | 1.23 |
Abbreviations: Ave, average; DQA, daily quality assurance; Max, maximum; Min, minimum; MRI, magnetic resonance imaging.
a The standard deviation is for the 3 experimental runs, while the average and range in the bottom 2 rows are for the 4 cardinal gantry angles.