A Feasible Application of Constrained Optimization in the IMRT System

The planning of intensity modulated radiation therapy cancer treatment poses an inverse problem and is usually solved by optimization methods. Treatment planning, in a majority of cases, requires restrictions to be imposed on the healthy organs, sensitive to the radiation, which justifies the use of constrained optimization. The application of these techniques in treatment planning usually involves serious complications and limitations due to the huge number of variables appearing in the planning process. This leads to large computation times and memory requirements. In this paper, strategies and algorithmic issues are proposed in order to cope with these limitations. The proposed methods have been applied and tested in real cases of prostate cancer, obtaining satisfactory results regarding computational limitations