Rigorous-two-Steps scheme of TRIPOLI-4® Monte Carlo code validation for shutdown dose rate calculation

AbstractThis article presents nuclide-specific organ dose rate coefficients for environmental external exposures due to soil contamination assumed as a planar source at a depth of 0.5 g cm−2 in the soil and submersion to contaminated air, for a pregnant female and its fetus at the 24th week of gestation. Furthermore, air kerma free-in-air coefficient rates are listed. The coefficients relate the organ equivalent dose rates (Sv s−1) to the activity concentration of environmental sources, in Bq m−2 or Bq m−3, allowing to time-integrate over a particular exposure period. The environmental radiation fields were simulated with the Monte Carlo radiation transport codes PHITS and YURI. Monoenergetic organ dose rate coefficients were calculated employing the Monte Carlo code EGSnrc simulating the photon transport in the voxel phantom of a pregnant female and fetus. Photons of initial energies of 0.015–10 MeV were considered including bremsstrahlung. By folding the monoenergetic dose coefficients with the nuclide decay data, nuclide-specific organ doses were obtained. The results of this work can be employed for estimating the doses from external exposures to pregnant women and their fetus, until more precise data are available which include coefficients obtained for phantoms at different stages of pregnancy.

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Determination of TG-43 dosimetric parameters for photon emitting brachytherapy sources

Journal of Biomedical Physics and Engineering ◽

10.31661/jbpe.v0i0.570 ◽

2017 ◽

Cited By ~ 1

Author(s):

A Mozaffari ◽

M Ghorbani

Keyword(s):

Monte Carlo ◽

Dose Rate ◽

Rate Constant ◽

Monte Carlo Code ◽

Treatment Planning Systems ◽

Radial Dose Function ◽

Anisotropy Function ◽

Radial Dose ◽

Good Agreement

Objective: Brachytherapy sources are widely used for the treatment of cancer. The report of Task Group No. 43 (TG-43) of American Association of Physicists in Medicine is known as the most common method for the determination of dosimetric parameters for brachytherapy sources. The aim of this study is to obtain TG-43 dosimetric parameters for 60Co, 137Cs, 192Ir and 103Pd brachytherapy sources by Monte Carlo simulation. Methods: In this study, 60Co (model Co0.A86), 137Cs (model 6520-67), 192Ir (model BEBIG) and 103Pd (model OptiSeed) brachytherapy sources were simulated using MCNPX Monte Carlo code. To simulate the sources, the exact geometric characterization of each source was defined in Monte Carlo input programs. Dosimetric parameters including air kerma strength, dose rate constant, radial dose function and anisotropy function were calculated for each source. Each input program was run with sufficient number of particle histories. The maximum type A statistical uncertainty in the simulation of the 60Co, 137Cs, 192Ir and 103Pd sources, were equal to 4%, 4%, 3.19% and 6.50%, respectively. Results: The results for dosimetry parameters of dose rate constant, radial dose function and anisotropy function for the 60Co, 137Cs, 192Ir and 103Pd sources in this study demonstrated good agreement with other studies. Conclusion: Based on the good agreement between the results of this study and other studies, the TG-43 results for Co0.A86 60Co, 67-65200 137Cs, BEBIG 192Ir and OptiSeed 103Pd sources are validated and can be used as input data in treatment planning systems (TPSs) and to validate the TPS calculations.

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Calculation of Spatial Distribution of Dose Rate in Air Under 300 keV Electron Beam Irradiation Using a Monte Carlo Code (EGS4-SPG code)

RADIOISOTOPES ◽

10.3769/radioisotopes.54.161 ◽

2005 ◽

Vol 54 (6) ◽

pp. 161-168 ◽

Cited By ~ 2

Author(s):

Teruyuki HAKODA ◽

Hiroaki HANAYA ◽

Hirohisa KANEKO ◽

Atsumi MIYASHITA ◽

Takuji KOJIMA

Keyword(s):

Monte Carlo ◽

Spatial Distribution ◽

Electron Beam ◽

Dose Rate ◽

Electron Beam Irradiation ◽

Monte Carlo Code ◽

Beam Irradiation

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Monte Carlo Computation of Dose-Volume Histograms in Structures at Risk of an Eye Irradiated with Heterogeneous Ruthenium-106 Plaques

Ocular Oncology and Pathology ◽

10.1159/000508113 ◽

2020 ◽

Vol 6 (5) ◽

pp. 353-359

Author(s):

Francisco J. Zaragoza ◽

Marion Eichmann ◽

Dirk Flühs ◽

Beate Timmermann ◽

Lorenzo Brualla

Keyword(s):

At Risk ◽

Monte Carlo ◽

Dose Rate ◽

Hot Spot ◽

Absorbed Dose ◽

Homogeneous Distribution ◽

Monte Carlo Code ◽

Absorbed Dose Rate ◽

Dose Volume Histograms ◽

Dose Volume

Background/Aims:The aim of this work is to compare Monte Carlo simulated absorbed dose distributions obtained from 106Ru eye plaques, whose heterogeneous emitter distribution is known, with the common homogeneous approximation. The effect of these heterogeneities on segmented structures at risk is analyzed using an anthropomorphic phantom. Methods:The generic CCA and CCB, with a homogeneous emitter map, and the specific CCA1364 and CCB1256 106Ru eye plaques are modeled with the Monte Carlo code PENELOPE. To compare the effect of the heterogeneities in the segmented volumes, cumulative dose-volume histograms are calculated for different rotations of the aforementioned plaques. Results:For the cornea, the CCA with the equatorial placement yields the lowest absorbed dose rate while for the CCA1364 in the same placement the absorbed dose rate is 33% higher. The CCB1256 with the hot spot oriented towards the cornea yields the maximum dose rate per unit of activity while it is 44% lower for the CCB. Conclusions:Dose calculations based on a homogeneous distribution of the emitter substance yield the lowest absorbed dose in the analyzed structures for all plaque placements. Treatment planning based on such calculations may result in an overdose of the structures at risk.

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RayXpert V1: 3D software for the gamma dose rate calculation by Monte Carlo

SNA + MC 2013 - Joint International Conference on Supercomputing in Nuclear Applications + Monte Carlo ◽

10.1051/snamc/201405316 ◽

2014 ◽

Author(s):

P. F. Peyrard ◽

P. Pourrouquet ◽

C. Dossat ◽

J. C. Thomas ◽

N. Chatry ◽

...

Keyword(s):

Monte Carlo ◽

Dose Rate ◽

Gamma Dose ◽

Gamma Dose Rate ◽

Rate Calculation ◽

3D Software

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A Monte Carlo investigation of the dose distribution for new I-125 Low Dose Rate brachytherapy source in water and in different media

Polish Journal of Medical Physics and Engineering ◽

10.2478/pjmpe-2019-0003 ◽

2019 ◽

Vol 25 (1) ◽

pp. 15-22 ◽

Cited By ~ 1

Author(s):

Zeinab Fardi ◽

Payvand Taherparvar

Keyword(s):

Experimental Data ◽

Monte Carlo ◽

Dose Rate ◽

Dose Distribution ◽

Monte Carlo Code ◽

Water Phantom ◽

Tissue Phantoms ◽

Radial Dose Function ◽

Brachytherapy Source ◽

Radial Dose

Abstract Permanent and temporary implantation of I-125 brachytherapy sources has become an official method for the treatment of different cancers. In this technique, it is essential to determine dose distribution around the brachytherapy source to choose the optimal treatment plan. In this study, the dosimetric parameters for a new interstitial brachytherapy source I-125 (IrSeed-125) were calculated with GATE/GEANT4 Monte Carlo code. Dose rate constant, radial dose function and 2D anisotropy function were calculated inside a water phantom (based on the recommendations of TG-43U1 protocol), and inside several tissue phantoms around the IrSeed-125 capsule. Acquired results were compared with MCNP simulation and experimental data. The dose rate constant of IrSeed-125 in the water phantom was about 1.038 cGy·h−1U−1 that shows good consistency with the experimental data. The radial dose function at 0.5, 0.9, 1.8, 3 and 7 cm radial distances were obtained as 1.095, 1.019, 0.826, 0.605, and 0.188, respectively. The results of the IrSeed-125 is not only in good agreement with those calculated by other simulation with MCNP code but also are closer to the experimental results. Discrepancies in the estimation of dose around IrSeed-125 capsule in the muscle and fat tissue phantoms are greater than the breast and lung phantoms in comparison with the water phantom. Results show that GATE/GEANT4 Monte Carlo code produces accurate results for dosimetric parameters of the IrSeed-125 LDR brachytherapy source with choosing the appropriate physics list. There are some differences in the dose calculation in the tissue phantoms in comparison with water phantom, especially in long distances from the source center, which may cause errors in the estimation of dose around brachytherapy sources that are not taken account by the TG43-U1 formalism.

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