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PubMed · 9048357

Monte Carlo based phase-space evolution for electron dose calculation.

D Scora·B A Faddegon
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Abstract

A system of computer codes based on phase-space evolution is developed and applied to low energy therapeutic electron beams. Monte Carlo (EGS4) is used to pre-calculate the electron transport and dose deposition in a 0.5 cm width cubic voxel. Dose calculations at larger scales are computed from the pre-calculated data using phase-space evolution. This approach has the theoretical accuracy of Monte Carlo with potentially significant speed gains resulting from the pre-calculation. This study demonstrates the accuracy of this technique while providing a preliminary assessment of the calculation time. For a 4.3 MeV electron beam in water with a 0.5 cm thick slab of either water (homogeneous), air, or aluminum at 1 cm depth, we observe differences relative to Monte Carlo of less than 3% along the central axis for a pencil-beam. For a 3.5 cm x 3.5 cm field we observe a maximum difference on the central axis of 4% in the build-up region and less than 0.1 cm in the fall-off region for all three phantoms. Calculation times are disappointing; however, there is high potential for their reduction to values comparable to or better than condensed history Monte Carlo while retaining clinically acceptable accuracy.

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AlgorithmsBiophysical PhenomenaBiophysicsElectronsMonte Carlo MethodPhantoms, ImagingRadiation DosageRadiotherapy, Computer-AssistedTechnology, RadiologicJournal Article

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BibTeXRIS

D Scora, B A Faddegon. 1997. Monte Carlo based phase-space evolution for electron dose calculation.. https://doi.org/10.1118/1.597925

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