Table 1 Worst and mean observed distortion measured from March 2017 to May 2018 on the MR-scanner
Geometric distortion over 15 months (mm) | ||||
|---|---|---|---|---|
Radial distance from isocenter | < 100 | 100–150 | 150–200 | 200–250 |
Mean distortion (1 SD) [range] | 0.2 (0.0) [0.1–0.2] | 0.3 (0.0) [0.2–0.4] | 0.5 (0.1) [0.4–0.7] | 1.9 (0.1) [1.7–2.0] |
Mean of max distortion (1 SD) [range] | 0.6 (0.1) [0.4–0.7] | 0.8 (0.2) [0.6–1.1] | 1.6 (0.3) [1.4–2.6] | 7.9 (0.3) [7.4–8.6] |