IMRT

This was all offline ART… Now: Online Adaptive Re-Planning

M. Ghilezan et al. (2004): Online image-guided intensity-modulated radiotherapy for prostate cancer: How much improvement can we expect? A theoretical assessment of clinical benefits and potential dose escalation by improving precision and accuracy of radiation therapy. IJRPBP 60(5) Idealized assumptions to investigate a ‘gold-standard’ benchmark online ART scheme: • daily pre-treatment imaging and online IMRT replanning • no intrafractional or other uncertainties => no PTV-margin necessary • evaluation using deformable dose accumulation of multiple CTs of 18 patients

Fx 1

Fx 2

Fx N

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CT

CT

CT

IMRT plan

IMRT plan

IMRT plan

no margin!

ESTRO IMRT course 2015 Adaptive Radiotherapy Brussels October 8th, 2015

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