| Autor: |
Caccia, Barbara, Blidéanu, Valentin, Le Roy, Maïwenn, Rabus, Hans, Tanner, Rick |
| Jazyk: |
angličtina |
| Rok vydání: |
2020 |
| Předmět: |
|
| DOI: |
10.12768/9rvp-fq82 |
| Popis: |
Radiation therapy has become more complex over the past few years with the use of new techniques like IMRT (Intensity Modulated Radiation Therapy) and stereotactic treatments. Moreover, optimisation of the radiotherapeutic treatment has become a critical point in the overall planning and delivery process due to the trend in dose-escalation with these new techniques and the associated risk for damage to healthy tissue. Typically, in techniques such as IMRT the dose distribution includes steep dose gradients with complex concave patterns. In order to calculate such complex three-dimensional distributions and deliver the proper dose to the tumour, the treatment planning system (TPS) has to perform complex calculations (usually in a short time) based on various approximations to the radiation transport process. Monte Carlo (MC) simulations can be beneficial in such circumstances – either as a means of undertaking the whole calculation (although this is still not often used in practice) or for validating the results achievedwith a commercial TPS (Rogers 2006). Moreover, MC calculations are commonly used in the establishment of the primary standards for calculation of correction factors not accessible to experimental determination. Working Group 6 (WG6) of EURADOS is dealing with various aspects of computational dosimetry in medical applications. The aim of WG6 is promoting good practice in the field of computational methods in radiation dosimetry for radiation protection and applications in radiation medicine. WG6 has been organizing intercomparisonson computational dosimetry for many years. In 2010 an intercomparison exercise was proposed with the aim of comparing the results obtained when different users apply different MC models to simulate a medical linear accelerator (LINAC), with approaches differing according to the MC code used and other parameters, such as the initial electron beam parameters and voxel size. This exercise has been called “Linac Action” and focused on the characterization of the therapeutic beam and on the calculation of the dose distributionsin water phantomsand in several heterogeneous phantoms for a nominal 12-MV photon beam (Caccia et al. 2017). The goal of the Linac Action was to monitor the state of the art regarding MC approaches for characterizing medical LINACs and to provide a learning-by-doing self-training exercise that supports MC users in developing the skills needed to (a) set up and calibrate a MC simulation of a real linear accelerator and (b) perform a dosimetric analysis bycomparing their results with measured reference data. The aim of this report is to provide the experimental data needed and a description of the MC modelling for those who want to start a Monte Carlo modelling activity in the field of oncological radiotherapy. Therefore, this report gives a compilation ofthedata needed for simulating the linear accelerator considered in the exercise and for evaluating the dose distribution obtained with such a MC simulation by comparing it with the measured dosimetric dataused in the intercomparison exercise. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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