IMRT

Fluence profile optimization (No MLC)

The minimum sits in a flat-pan valley, the search direction is well defined in few (ca. 100), but vague in most dimensions (ca. 10000), a multiplicity of optimum solutions exists.

Problems for the optimization algorithm: convergence in end game is very slow – terminate long before convergence same solution may not be reached twice, although the cost functions have identical values no local minima, but still difficulties to find the optimum!

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

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