IMRT

courtesy M. Alber

MLC delivery deviates from the ideal profiles

sequencing: translation into (coarser, but deliverable) segments

step and shoot

optimal fluence profile

sliding-window dynamic

⇒ (1) Quality loss due to discretization

improvement

⇒ (2) Hi-quality dose calculation of segment doses changes dose distribution! (usually: to the worse)

ESTRO IMRT course 2015 IMRT optimization: algorithms&cost functions Brussels October 5th, 2015

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