Comparison of parameters related on beam profile, PDDs and output factor from commissioning data of linear accelerators TrueBeam®

For commissioning a linear accelerator for clinical use, medical physicists are faced with many challenges including the need for precision, a variety of testing methods, data validation, the lack of standards, and time constraints. Since commissioning beam data are treated as a reference and ultimately used by treatment planning systems, it is vitally important that the collected data are of the highest quality to avoid dosimetric and patient treatment errors that may subsequently lead to a poor radiation outcome. Therefore, it is essential that the data commissioning be performed with adequate equipments and with the necessary knowledge because these data will serve as the basis for the calculation of the dose of the treatment of the patients during the operation of the linear accelerator. This work aimed the analysis and comparison of collected data from commissioning tests of two linear accelerators TrueBeam® da Varian Medical Systems for a 6 MV photon beams. The data related to beam profile, percentage depth dose (PDDs) curves and output factor were analyzed. The overarching goal of this work is to generate a set of data with technical guidelines that may assist other institutions embarking on TrueBeam commissioning, thereby improving the quality and safety of the commissioning process. (author)