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ESTRO IMRT course 2015
IMRT optimization: algorithms&cost functions
Brussels October 5th, 2015
-19-
Static gantry, dMLC:
no distant local minima for `easy’ MLCs,
(e.g. sliding window)
proven algorithm for solution
Principles: The optimization problem for the
different IMRT techniques
Static gantry, step&shoot:
local minima possible, but good heuristics for
(‘step&shoot’ IMRT)
avoiding them (MLC sequencer)
(Notice: algorithm converges, heuristic produces a result)
Rotational-IMRT:
So many local solutions that it becomes impossible to
(VMAT, Rapid Arc ©…)
identify
the global one, bold heuristics for avoiding
the inevitable: getting trapped in a local minimum.