Table I.
Deviations from the beam central axis (CAX) of the center of the dose profiles measured by various detectors in a 1.5 T magnetic field in both the inline direction (parallel with the magnetic field) and the crossline direction (perpendicular to the magnetic field). CAX deviations in the crossline direction are shown based on the value measured from the raw data and the value when corrected for the effects of volume averaging. Uncertainty is ±0.1 mm. Positive values indicate a shift towards the average direction of the Lorentz force (patient left).
| CAX Deviations (mm) | |||
|---|---|---|---|
| Detectors | Inline | Crossline (Raw value) |
Crossline (Corrected) |
| PTW 30013 Farmer | N/A | 2.36 | 2.16 |
| PTW Semiflex 3D | −0.07 | 2.05 | 1.92 |
| PTW PinPoint 3D | 0.04 | 1.07 | 1.01 |
| PTW microDiamond | 0.09 | 0.83 | 0.79 |
| PTW Diode SRS | 0.01 | 0.83 | 0.82 |
| PTW Diode P | 0.01 | 0.55 | 0.54 |