ON IMPROVING PHYSICAL SELECTIVITY IN THE TREATMENT OF CANCER - A SYSTEMS MODELING AND OPTIMIZATION APPROACH

This paper presents the results arising from a practical implementatio n of a novel hybrid optimisation scheme, used to solve the inverse pro blem in radiotherapy treatment planning (RTP). A matrix-based beam mod el which has been developed making use of a control systems modelling approach is used, together with a hybrid optimisation scheme. Patient- specific compensator profiles are deduced from the intensity modulated beam profiles obtained from the hybrid scheme, with use being made of an exponential attenuation factor coupled with a point spread convolu tion function to account for the scatter in the compensator. A good ag reement between the predicted and actual conformational distributions is achieved. Copyright (C) 1997 Elsevier Science Ltd.