Advanced Physics for Brachytherapy 2018

Inverse Optimisation and Planning: A Multi-Objective (MO) Problem

Example: Bi-Objective Pareto Fronts obtained for 22 prostate implants . The variety shows that a single objective optimization does not give always a good result. In general a strong trade-off is observed. *

PTV

Example of a Pareto Front: there is a strong trade-off between the objectives/ objective functions f 1 and f 2 . The smaller the f 1 value is that we want the larger is the corresponding f 2 value . The “ideal point/plan” I lies far away form the front. There is a high dependence on the selection of the f 1 value.

Homogeneity

Conformity

*Lahanas, Milickovic, Baltas, Zamboglou: “Application of Multiobjective Evolutionary Algorithms for Dose Optimization Problems in Brachytherapy”, EMO 2001, LNCS 1993, 574-587, 2001.