CT-based MCNPX dose calculations for gynecology brachytherapy employing a Henschke applicator

Energy deposition and dose enhancement using Monte Carlo derivative sampling: applications in brachytherapy

“…The effects of such artifacts for electron transport have been investigated (Almansa et al, 2006;Koivunoro et al, 2012;Archambault & Mainegra-Hing, 2015) with EGSnrc, GEANT and PENELOPE codes and in some cases 'large discrepancies' (> 3%) have been found between MCNP5 dose distributions and the 'reference codes' concluding that MCNP5 electron transport calculations are not accurate at all energies and in every medium by general clinical standards. Similarly, comparisons have been made (Yu et al, 2017) between EGSnrc, GEANT4, MCNP5 and PENELOPE for mono-energetic electron beams in a water-filled sphere of radius varying from 0.25-4.5 cm for beam energies of 0.5 MeV, 1.0 MeV, and 5.0 MeV and found to have differences below 10% by tuning parameters associated with multiple scattering algorithms at the expense of increased computation time. It can thus be anticipated that MCNP5 may differ due to its inadequate low-energy treatment of electron transport.…”

“…The second objective of this work was to estimate the effect of small changes in solution concentration on the resulting radiation dose from a single MC simulation rather than estimating changes from MC re-runs where the effect is vulnerable to be masked in the uncertainty of the estimate itself. Such MC perturbation analysis has applications in brachytherapy for estimating dose perturbations when implants are present in the vicinity of an organ receiving radiation from an implanted source (Yu et al, 2017). However, it is yet to be used in simulation for brachytherapy studies and can provide great computational efficiency leading to optimal designs based on 'best' experimental parameters such as radiation energy, concentration of gold in solution and material placement for maximizing an objective function of interest.…”