Application of the OWA Operator in the Beam Angle Optimization and Intensity Problems in IMRT
Radiation Therapy, IMRT, OWA operator, Experimental Algorithms
Radiation therapy is an extremely important method in the treatment of cancer. The main challenge is to deliver the minimal dose to the tumor without exposing the healthy organs to radiation beyond the allowable limit. One of the main approaches to radiotherapy is intensity-modulated radiotherapy therapy (IMRT). Over the years, many researchers have proposed algorithms to solve the IMRT’s main difculty, the ploblem is to automate the selection of beam angles for a better dose distribution. In this research is presented an algorithm that seeks the ideal balance between a set of small angles and a dose distribution that respects the medical prescriptions to certain patients. The proposed algorithm uses two new mathematical models and the Ordered Weighted Average (OWA) operator as a criterion of preference in the choice of solution. The algorithm was evaluated concerning computational time and solution quality, computational experiments were performed in ten patients with liver cancer. The results were satisfactory, fnding viable solutions for eight patients.