SUFT111: Investigation of the Attila Deterministic Solver as a Supplement to Monte Carlo for Calculating OutOfField Radiotherapy Dose
Abstract
Purpose: To use the Attila deterministic solver as a supplement to Monte Carlo for calculating outoffield organ dose in support of epidemiological studies looking at the risks of second cancers. Supplemental dosimetry tools are needed to speed up dose calculations for studies involving largescale patient cohorts. Methods: Attila is a multigroup discrete ordinates code which can solve the 3D photonelectron coupled linear Boltzmann radiation transport equation on a finiteelement mesh. Dose is computed by multiplying the calculated particle flux in each mesh element by a mediumspecific energy deposition crosssection. The outoffield dosimetry capability of Attila is investigated by comparing average organ dose to that which is calculated by Monte Carlo simulation. The test scenario consists of a 6 MV external beam treatment of a female patient with a tumor in the left breast. The patient is simulated by a wholebody adult reference female computational phantom. Monte Carlo simulations were performed using MCNP6 and XVMC. Attila can export a tetrahedral mesh for MCNP6, allowing for a direct comparison between the two codes. The Attila and Monte Carlo methods were also compared in terms of calculation speed and complexity of simulation setup. A key perquisite for this work was the modeling ofmore »
 Authors:
 Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD (United States)
 Varian Medical Systems, Gig Harbor, WA (United States)
 Publication Date:
 OSTI Identifier:
 22642353
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 43; Journal Issue: 6; Other Information: (c) 2016 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 60 APPLIED LIFE SCIENCES; 61 RADIATION PROTECTION AND DOSIMETRY; COMPUTER CODES; COMPUTERIZED SIMULATION; DOSIMETRY; FEMALES; LINEAR ACCELERATORS; MAMMARY GLANDS; MONTE CARLO METHOD; PATIENTS; PERFORMANCE
Citation Formats
Mille, M, Lee, C, and Failla, G. SUFT111: Investigation of the Attila Deterministic Solver as a Supplement to Monte Carlo for Calculating OutOfField Radiotherapy Dose. United States: N. p., 2016.
Web. doi:10.1118/1.4956247.
Mille, M, Lee, C, & Failla, G. SUFT111: Investigation of the Attila Deterministic Solver as a Supplement to Monte Carlo for Calculating OutOfField Radiotherapy Dose. United States. doi:10.1118/1.4956247.
Mille, M, Lee, C, and Failla, G. 2016.
"SUFT111: Investigation of the Attila Deterministic Solver as a Supplement to Monte Carlo for Calculating OutOfField Radiotherapy Dose". United States.
doi:10.1118/1.4956247.
@article{osti_22642353,
title = {SUFT111: Investigation of the Attila Deterministic Solver as a Supplement to Monte Carlo for Calculating OutOfField Radiotherapy Dose},
author = {Mille, M and Lee, C and Failla, G},
abstractNote = {Purpose: To use the Attila deterministic solver as a supplement to Monte Carlo for calculating outoffield organ dose in support of epidemiological studies looking at the risks of second cancers. Supplemental dosimetry tools are needed to speed up dose calculations for studies involving largescale patient cohorts. Methods: Attila is a multigroup discrete ordinates code which can solve the 3D photonelectron coupled linear Boltzmann radiation transport equation on a finiteelement mesh. Dose is computed by multiplying the calculated particle flux in each mesh element by a mediumspecific energy deposition crosssection. The outoffield dosimetry capability of Attila is investigated by comparing average organ dose to that which is calculated by Monte Carlo simulation. The test scenario consists of a 6 MV external beam treatment of a female patient with a tumor in the left breast. The patient is simulated by a wholebody adult reference female computational phantom. Monte Carlo simulations were performed using MCNP6 and XVMC. Attila can export a tetrahedral mesh for MCNP6, allowing for a direct comparison between the two codes. The Attila and Monte Carlo methods were also compared in terms of calculation speed and complexity of simulation setup. A key perquisite for this work was the modeling of a Varian Clinac 2100 linear accelerator. Results: The solid mesh of the torso part of the adult female phantom for the Attila calculation was prepared using the CAD software SpaceClaim. Preliminary calculations suggest that Attila is a userfriendly software which shows great promise for our intended application. Computational performance is related to the number of tetrahedral elements included in the Attila calculation. Conclusion: Attila is being explored as a supplement to the conventional Monte Carlo radiation transport approach for performing retrospective patient dosimetry. The goal is for the dosimetry to be sufficiently accurate for use in retrospective epidemiological investigations.},
doi = {10.1118/1.4956247},
journal = {Medical Physics},
number = 6,
volume = 43,
place = {United States},
year = 2016,
month = 6
}

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