Robust broad beam optimization for proton therapy

A proton therapy planning device comprising:

• a computer;
• and
• at least one non-transitory storage medium storing instructions readable and executable by the computer to perform a proton therapy planning operations including:
• generating a proton therapy plan with parameters defining at least a range band implemented by a range modulator device;
• calculating a nominal dose distribution to be delivered to a volume of a patient by performing proton therapy on the volume of the patient in accordance with the proton therapy plan;
• and
• adjusting the parameters defining the range band to improve conformance of the calculated nominal dose distribution with a planning target volume within the volume of the patient, the adjusting operation being repeated for each error scenario of a set of error scenarios.

A proton therapy planning method comprising:

• calculating a nominal dose distribution to be delivered to a volume by performing proton therapy on the volume according to a proton therapy plan having parameters defining at least a range compensator shape;
• for each error scenario of a set of error scenarios, computing a difference between the nominal dose distribution and a perturbed dose distribution calculated to be delivered to the volume modified by the error scenario by performing proton therapy on the volume modified by the error scenario in accordance with the proton therapy plan;
• adjusting the parameters of the proton therapy plan to reduce an aggregation of the computed differences;
• and
• storing the proton therapy plan with the parameters of the proton therapy plan adjusted by the adjusting operation.