A novel approach to quality assurance of radiation treatments with a visual interface of GEANT4 for Varian TrueBeam STx

The Monte Carlo (MC) technique, widely recognized as one of the most reliable methods for simulating radiation transport, is commonly employed in radiotherapy. An MC-based simulation softwares such as GEANT4, require a certain level of programing knowledge due to its complex structure. Through the visual interface we have developed, the Varian TrueBeam STx machine used in radiotherapy treatments can be easily utilized in GEANT4 calculations for the treatment quality assurance (QA). Following the geometric modeling and validation of the Varian TrueBeam STx for GEANT4, a graphical user interface (GUI) was designed that allows the use of various parameters of the simulation model by providing user-defined inputs. During the interface design, the QT framework was employed for the GUI, while the coding section involved the use of Python and C +  + programing languages. The visual interface enables the dynamic transfer of optional simulation information, generated either through user input or obtained from the Varian Eclipse treatment planning system (TPS) to the simulation model. This allows the execution of the GEANT4 simulation. The usage of simulation parameters available in the GUI and the transfer of these parameters to the GEANT4 were tested on CentOS (7), Ubuntu (20.04.6 LTS), Mint (20.3 Una), and MacOS (14.2.1 Sonoma) operating systems. The visual interface of the Varian TrueBeam STx has been introduced as a user-friendly visual interface for medical physicists aiming to perform MC studies using the Varian TrueBeam STx. It is designed for ease of use and shows promise as a third-party quality assurance add-on for clinical applications of radiation therapy.