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Absorbed fractions in a voxel-based phantom calculated with the MCNP-4B code.

H Yoriyaz·A dos Santos·M G Stabin·R Cabezas
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Abstract

A new approach for calculating internal dose estimates was developed through the use of a more realistic computational model of the human body. The present technique shows the capability to build a patient-specific phantom with tomography data (a voxel-based phantom) for the simulation of radiation transport and energy deposition using Monte Carlo methods such as in the MCNP-4B code. MCNP-4B absorbed fractions for photons in the mathematical phantom of Snyder et al. agreed well with reference values. Results obtained through radiation transport simulation in the voxel-based phantom, in general, agreed well with reference values. Considerable discrepancies, however, were found in some cases due to two major causes: differences in the organ masses between the phantoms and the occurrence of organ overlap in the voxel-based phantom, which is not considered in the mathematical phantom.

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AlgorithmsDigestive SystemHeartHumansLungMaleMonte Carlo MethodPancreasPhantoms, ImagingPhotonsRadiometryRadiotherapy Planning, Computer-AssistedSoftwareSpleenTomography, X-Ray ComputedJournal Article

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H Yoriyaz, A dos Santos, M G Stabin, R Cabezas. 2000. Absorbed fractions in a voxel-based phantom calculated with the MCNP-4B code.. https://doi.org/10.1118/1.599021

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