Biased Multi-Objective Function Optimization in Radiotherapy Inverse Planning

摘要

A new RT inverse planning optimization technique has been proposed. The proposed method was used to find the optimum location of a radiation therapy beam to maximize the dose to a tumor in 3-D Cartesian geometry under the constraint of a pre-determined minimum dose. Two other sensitive organs were assumed to be present near the targeted tumor and the doses received by them were minimized under the constraint of a pre-determined maximum dose. Optimization results showed not only a solution where all objective functions and constraints are met but also a "family" of solutions from which a user can choose. The existence of multiple solutions to the problems analyzed enabled the trade-off of sensitive organ dose margin with higher tumor dose. This was accomplished by increasing the importance of meeting the tumor objective function eight times that of the organs'.