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The proton field treatment parameters for a prostate cancer field and a medulloblastoma field. R90 is the 90% range of the protons in water, M90−90 is the modulation width and the field size is given at the aperture. Full modulation means that the relative dose is 100% at the entrance.
| Field name | R90 (g∕cm2) | M90−90 (cm) | Field size (cm2) |
|---|---|---|---|
| Prostate cancer | 28.8 | 10.4 | 45.2 |
| Cranial medulloblastoma | 15.8 | Full | 184.4 |
