Quality assurance for the use of computational methods in dosimetry: activities of EURADOS Working Group 6 ‘Computational Dosimetry’

Abstract

Working Group (WG) 6 ‘Computational Dosimetry’ of the European Radiation Dosimetry Group promotes good practice in the application of computational methods for radiation dosimetry in radiation protection and the medical use of ionising radiation. Its cross-sectional activities within the association cover a large range of current topics in radiation dosimetry, including more fundamental studies of radiation effects in complex systems. In addition, WG 6 also performs scientific research and development as well as knowledge transfer activities, such as training courses. Monte Carlo techniques, including the use of anthropomorphic and other numerical phantoms based on voxelised geometrical models, play a strong part in the activities pursued in WG 6. However, other aspects and techniques, such as neutron spectra unfolding, have an important role as well. A number of intercomparison exercises have been carried out in the past to provide information on the accuracy with which computational methods are applied and whether best practice is being followed. Within the exercises that are still ongoing, the focus has changed towards assessing the uncertainty that can be achieved with these computational methods. Furthermore, the future strategy of WG 6 also includes an extension of the scope toward experimental benchmark activities and evaluation of cross-sections and algorithms, with the vision of establishing a gold standard for Monte Carlo methods used in medical and radiobiological applications.

Consistency checks of results from a Monte Carlo code intercomparison for emitted electron spectra and energy deposition around a single gold nanoparticle irradiated by X-rays

“…Prompted by the large variety of results reported in literature regarding this dose enhancement ( Mesbahi 2010, Vlastou et al 2020, Moradi et al 2021, a code intercomparison exercise was organized as a joint activity of the Working Groups 6 "Computational Dosimetry" ( Rabus et al 2021a) and 7 "Internal Rabus et al…”

Intercomparison of Monte Carlo calculated dose enhancement ratios for gold nanoparticles irradiated by X-rays: Assessing the uncertainty and correct methodology for extended beams

“…As the discrepancies in literature regarding DERs on the sub-cellular scale could in principle be due to different cross section data sets employed by different codes, a code intercomparison exercise was conducted as a joint activity of Working Groups 7 "Internal Dosimetry" and 6 "Computational Dosimetry" of the European Radiation Dosimetry Group [23,24,25]. The exercise was an intercomparison of Monte Carlo simulations for the case of dose enhancement in water from two sizes (50 nm and 100 nm diameter) of single spherical gold nanoparticles (GNP) under X-ray irradiation [26,27].…”

Development and validation of the low‐cost pregnant female physical phantom for fetal dosimetry in MV photon radiotherapy

“…Though MC simulations are valuable research methods, their setup and computational time can take a significant amount of time 26,27 . In addition, MC simulations are subject to uncertainties such as underestimation of the absorbed dose outside the primary radiation field 28–32 . Therefore, physical in‐phantom measurements are indispensable and allow an experimental measurement of the fetal dose enabling validation of MC simulations.…”

“… 26 , 27 In addition, MC simulations are subject to uncertainties such as underestimation of the absorbed dose outside the primary radiation field. 28 , 29 , 30 , 31 , 32 Therefore, physical in‐phantom measurements are indispensable and allow an experimental measurement of the fetal dose enabling validation of MC simulations. Moreover, in the clinical environment, physical measurements are often required for such pregnancy cases and further allow establishing protocols for estimating dose conversion coefficients for in vivo dosimetry.…”