Physics Bucharest 2017

Robust control • A prerequisite of high precision dose delivery is high precision of targeting. • If (all) involved uncertainties are not taken into account → reduced benefit of highly conformal techniques. • Margins are a robust strategy for target coverage with a clear price (healthy tissues irradiation) … but in some cases are not enough. • To fully exploit the potential of IMRT/PT in complex cases with considerable organ motion, real time image guidance is necessary. • In the absence of accurate prognostic factors an adaptive approach (repeat imaging – calculation – planning) is recommended in PT. • A plan is robust if treatment goals are met despite uncertainties in the patient model and the plan remains acceptable over a range of likely variations. • Optimal dose distribution → dose conformity, healthy tissue sparing and robustness towards uncertainties.