Medidas de filtros dinâmicos em radioterapia.

Abstract

It is known that to ensure a better outcome in the treatment of patients in Radiotherapy, there should be a constancy of the physical parameters as well as a verification of the worked planning system. The following work presents a study of the physical properties of the dynamic lters of the linear accelerator 6ex, from Varian Medical Systems, using experimental veri cation by comparing them with calculations made by the planning system Eclipse under the same conditions. The lter factors were determined for symmetrical and asymmetrical elds to the central axis and off of it, by checking the influence of collimators X and Y in di erent openings, there is also the dependence of the lter factor with the depth, with the increase of the elds and angles used in the lters, and the eld pro les for specifi c depths. The interpretation of the results of the lter factors, enables calculations in radiotherapy treatment planning, for a possible lack of planning system.