IMRT

Cost Functions can be Balanced by Weight Factors: the Lagrange Function

∑ M

Combine all goals to one weighted sum:

L

F

λ

=

j j

1

j

=

∑ M

,1

0

j λ

j λ

=

≥

1

j

=

…and minimize the Lagrange Function L . Tuning the weight factors makes all solutions in Solution Space accessible. Problem: find the right set of weights that produces a dose distribution as minimizer of L which is ` closest to the intended` treatment. j λ

This is a decision to be made by the user, not the software

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

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