EVALUATION OF THE DOSE ALGORITHM-BASED ON THE SCATTER MODEL APPLIED FOR NEUTRON THERAPY TREATMENT PLANNING

The algorithm based on the scatter model was successfully applied in t otal dose (neutron plus gamma) calculations for Harper Hospital d(48.5 ) + Be neutron beam. The central axis and the lateral beam profiles as well as the peak scatter factors were measured for a number of rectan gular and irregularly shaped fields. These data were used to calculate the tissue- and scatter-to-air ratios (TAR and SAR) as well as to det ermine the beam parameters pertinent to the treatment planning algorit hm and to evaluate its accuracy in clinical cases. The agreement betwe en the measured data and the data derived from the treatment planning program is usually within 2% for the central axis points and about 5% for the lateral beam profiles.