Research Masterclass in Radiotherapy Physics 2017

Probabilistic / robust planning to replace PTV/PRV concepts

conventional planning

probabilistic planning

CTV

OAR

CTV

OAR

95% PTV P(98% of CTV gets dose > 95%) = 98%

P(98% of CTV gets dose > 95%) = 98%

Probabilistic / robust planning to replace PTV/PRV concepts • Directly optimize CTV/OAR dose • HOW: - cost functions include knowledge on motion OR - simultaneously optimize multiple scenario’s • If prostate moves anteriorly, then also the proximal part of the rectum • Automatically generate high dose area around CTV • Challenges: (individualized) motion pattern,

anatomy deformation, calculation speed • Highly relevant for IMPT (Bragg peak)

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