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Joya M, Nedaie HA, Geraily G, Rezaei H, Bromand A, Ghorbani M, Sheikhzadeh P. Investigation of TG-43 Dosimetric Parameters for 192Ir Brachytherapy Source Using GATE Monte Carlo Code. J Med Phys 2023; 48:268-273. [PMID: 37969149 PMCID: PMC10642593 DOI: 10.4103/jmp.jmp_41_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/29/2023] [Accepted: 06/21/2023] [Indexed: 11/17/2023] Open
Abstract
Purpose According to the revised Task Group number 43 recommendations, a brachytherapy source must be validated against a similar or identical source before its clinical application. The purpose of this investigation is to verify the dosimetric data of the high dose rate (HDR) BEBIG 192Ir source (Ir2.A85-2). Materials and Methods The HDR 192Ir encapsulated seed was simulated and its main dosimetric data were calculated using Geant4 Application for Tomographic Emission (GATE) simulation code. Cubic cells were used for the calculation of dose rate constant and radial dose function while for anisotropy function ring cells were used. DoseActors were simulated and attached to the respective cells to obtain the required data. Results The dose rate constant was obtained as 1.098 ± 0.003 cGy.h - 1.U - 1, differing by 1.0% from the reference value reported by Granero et al. Similarly, the calculated values for radial dose and anisotropy functions presented good agreement with the results obtained by Granero et al. Conclusion The results of this study suggest that the GATE Monte Carlo code is a valid toolkit for benchmarking brachytherapy sources and can be used for brachytherapy simulation-based studies and verification of brachytherapy treatment planning systems.
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Affiliation(s)
- Musa Joya
- Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran, Iran
- Department of Radiology, Kabul University of Medical Sciences, Kabul, Afghanistan
| | - Hassan Ali Nedaie
- Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran, Iran
| | - Ghazale Geraily
- Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran, Iran
| | - Hadi Rezaei
- Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran, Iran
- Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran
| | - Awaz Bromand
- Department of Physics, Ghor Institute of Higher Education, Ghor, Afghanistan
| | - Mahdi Ghorbani
- Department of Biomedical Engineering and Medical Physics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Peyman Sheikhzadeh
- Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran, Iran
- Department of Nuclear Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
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Safigholi H, Chamberland MJP, Taylor REP, Martinov MP, Rogers DWO, Thomson RM. Update of the CLRP Monte Carlo TG-43 parameter database for high-energy brachytherapy sources. Med Phys 2023; 50:1928-1941. [PMID: 36542404 DOI: 10.1002/mp.16176] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 11/11/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
PURPOSE To update and extend version 2 of the Carleton Laboratory for Radiotherapy Physics (CLRP) TG-43 dosimetry database (CLRP_TG43v2) for high-energy (HE, ≥50 keV) brachytherapy sources (1 169 Yb, 23 192 Ir, 5 137 Cs, and 4 60 Co) using egs_brachy, an open-source EGSnrc application. A comprehensive dataset of TG-43 parameters is compiled, including detailed source descriptions, dose-rate constants, radial dose functions, 1D and 2D anisotropy functions, along-away dose-rate tables, Primary and Scatter Separated (PSS) dose tables, and mean photon energies escaping each source. The database also documents the source models which are freely distributed with egs_brachy. ACQUISITION AND VALIDATION METHODS Datasets are calculated after a recoding of the source geometries using the egs++ geometry package and its egs_brachy extensions. Air kerma per history is calculated in a 10 × 10 × $\,{\times}\, 10\,{\times}\,$ 0.05 cm3 voxel located 100 cm from the source along the transverse axis and then corrected for the lateral and thickness dimensions of the scoring voxel to give the air kerma on the central axis at a point 100 cm from the source's mid-point. Full-scatter water phantoms with varying voxel resolutions in cylindrical coordinates are used for dose calculations. Most data (except for 60 Co) are based on the assumption of charged particle equilibrium and ignore the potentially large effects of electron transport very close to the source and dose from initial beta particles. These effects are evaluated for four representative sources. For validation, data are compared to those from CLRP_TG43v1 and published data. DATA FORMAT AND ACCESS Data are available at https://physics.carleton.ca/clrp/egs_brachy/seed_database_v2 or http://doi.org/10.22215/clrp/tg43v2 including in Excel (.xlsx) spreadsheets, and are presented graphically in comparisons to previously published data for each source. POTENTIAL APPLICATIONS The CLRP_TG43v2 database has applications in research, dosimetry, and brachytherapy planning. This comprehensive update provides the medical physics community with more precise and in some cases more accurate Monte Carlo (MC) TG-43 dose calculation parameters, as well as fully benchmarked and described source models which are distributed with egs_brachy.
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Affiliation(s)
- Habib Safigholi
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
| | - Marc J P Chamberland
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
| | - Randle E P Taylor
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
| | - Martin P Martinov
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
| | - D W O Rogers
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
| | - Rowan M Thomson
- Carleton Laboratory for Radiotherapy Physics (CLRP), Department of Physics, Carleton University, Ottawa, Ontario, Canada
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BEBIG 60Co HDR brachytherapy source dosimetric parameters validation using GATE Geant4-based simulation code. Heliyon 2022; 8:e09168. [PMID: 35368537 PMCID: PMC8971593 DOI: 10.1016/j.heliyon.2022.e09168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/20/2022] [Accepted: 03/07/2022] [Indexed: 11/21/2022] Open
Abstract
Purpose This study aims to validate the dosimetric characteristics of High Dose Rate (HDR) 60Co source (Co0.A86 model) using GATE Geant4-based Monte Carlo code. According to the recommendation of the American Association of Physicists in Medicine (AAPM) task group report number 43, the dosimetric parameters of a new brachytherapy source should be verified either experimentally or by Monte Carlo calculation before clinical applications. The validated 60Co source in this study will be used for the simulation of intensity-modulated brachytherapy (IMBT) of vaginal cancer using the same GATE Geant4-based Monte Carlo code in the future. Materials and methods GATE (version 9.0) simulation code was used to model and calculate the required TG-43U1 dosimetric data of the 60Co HDR source. DoseActors were defined for calculation of dose rate constant, radial dose function, and anisotropy function in a water phantom with an 80 cm radius. Results The dose rate constant was obtained as 1.070±0.008cGy.h−1.U−1 which shows a relative difference of 2.01% compared to the consensus value, 1.092 cGy.h−1.U−1. The calculated results of anisotropy and radial dose functions starting from 0.1 cm to 10 cm around the source showed excellent agreement with the results of published studies. The mean variation of the radial dose and anisotropy functions values from the consensus data were 1% and 0.9% respectively. Conclusion Findings from this investigation revealed that the validation of the HDR 60Co source is feasible by the GATE Geant4-based Monte Carlo code. As a result, the GATE Monte Carlo code can be used for the verification of the brachytherapy treatment planning system.
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Elboukhari S, Yamni K, Ouabi H, Bouassa T, Ait Mlouk L. Technical note: Dosimetric study for the new BEBIG 60Co HDR source used in brachytherapy in water and different media using Monte Carlo N-Particle eXtended code. Appl Radiat Isot 2020; 159:109087. [PMID: 32250762 DOI: 10.1016/j.apradiso.2020.109087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 02/01/2020] [Accepted: 02/19/2020] [Indexed: 10/24/2022]
Abstract
This work aims to study the dosimetrc parameters of the new 60Co-source model Co0.A86 used in high dose rate brachytherapy and manufactured by BEBIG (Eckert & Ziegler BEBIG GmbH, Germany). The radial dose function, 2D along&away dose rates and the dose rate constant were investigated in a water phantom. Accordingly, we use the recommendations from the AAPM and ESTRO on dose calculation for high-energy (average energy higher than 50 keV) photon-emitting brachytherapy sources cited in the HEBD working group report. Furthermore, we compared the obtained results with the quoted values in the previous studies. The value of air-kerma strength calculated in this work was 3.030 ± 0.002 UBq-1. Moreover, the radial dose function and 2D along&away dose rates are evaluated in different tissues and compared with the results obtained in the water and we found a notable difference. To reach the goal we have used MCNPX code for simulation.
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Affiliation(s)
- Said Elboukhari
- EMaMePS, Department of Chemistry, Faculty of Sciences, Molay Ismail University of Meknes, Morocco.
| | - Khalid Yamni
- EMaMePS, Department of Chemistry, Faculty of Sciences, Molay Ismail University of Meknes, Morocco
| | - Hmad Ouabi
- Center of Oncology ALAZHAR, Rabat, Morocco
| | - Taoufiq Bouassa
- Faculty of Sciences, Mohammed V University of Rabat, Morocco
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Measurements and Monte Carlo calculation of radial dose and anisotropy functions of BEBIG 60Co high-dose-rate brachytherapy source in a bounded water phantom. J Contemp Brachytherapy 2020; 11:563-572. [PMID: 31969915 PMCID: PMC6964345 DOI: 10.5114/jcb.2019.91224] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 12/03/2019] [Indexed: 11/17/2022] Open
Abstract
Purpose The study compared the experimentally measured radial dose function, g(r), and anisotropy function, F(r,θ), of a BEBIG 60Co (Co0.A86) high-dose-rate (HDR) source in an in-house designed water phantom with egs_brachy Monte Carlo (MC) calculated values. MC results available in the literature were only for unbounded phantoms, and there are no currently published data in the literature for experimental data compared to MC calculations for a bounded phantom. Material and methods egs_brachy is a fast EGSnrc application designed for brachytherapy applications. For unbounded phantom calculation, we considered a cylindrical phantom with a length and diameter of 80 cm and used liquid water. These egs_brachy calculated TG43U1 parameters were compared with the consensus data. Upon its validation, we experimentally measured g(r) and F(r,θ) in a precisely machined 30 × 30 × 30 cm3 water phantom using TLD-100 and EBT2 Gafchromic Film and compared it with the egs_brachy results of the same geometry. Results The TG43U1 dosimetric dataset calculated using egs_brachy was compared with published data for an unbounded phantom, and found to be in good agreement within 2%. From our experimental results of g(r) and F(r,θ), the observed variation with the egs_brachy code calculation is found to be within the acceptable experimental uncertainties of 3%. Conclusions In this study, we validated the egs_brachy calculation of the TG43U1 dataset for the BEBIG 60Co source for an unbounded geometry. Subsequently, we measured the g(r) and F(r,θ) for the same source using an in-house water phantom. In addition, we validated these experimental results with the values calculated using the egs_brachy MC code, with the same geometry and similar phantom material as used in the experimental methods.
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39 Use of the GATE/GEANT4 platform in high dose rate brachytherapy: Dosimetric study of a Cobalt 60 source. Phys Med 2018. [DOI: 10.1016/j.ejmp.2018.09.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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An automated dose verification software for brachytherapy. J Contemp Brachytherapy 2018; 10:478-482. [PMID: 30479626 PMCID: PMC6251445 DOI: 10.5114/jcb.2018.79396] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 10/15/2018] [Indexed: 11/27/2022] Open
Abstract
Purpose To report an implementation method and the results of independent brachytherapy dose verification software (DVS). Material and methods The DVS was developed based on Visual C++ and adopted a modular structure design. The DICOM RT files exported from a treatment planning system (TPS) were automatically loaded into the DVS. The DVS used the TG-43 formalism for dose calculation. A total of 15 cervical cancer patients who underwent brachytherapy were retrospectively selected to test the DVS. Dosimetric parameters and γ analysis (0.1 cm, 5%) were used to evaluate the dose differences between the DVS and the TPS. Results Compared with the TPS dose, the γ pass rates of the dose calculated by the DVS were higher than 98%. For the clinical target volume (CTV), the dosimetric differences were less than 0.63% for D90% and D100%. For the bladder, rectum, and sigmoid, the agreement of D0.1cc, D1cc, and D2cc were within a 0.78% level. Conclusions With minimal human-computer interactions, the DVS can verify the accuracy of doses calculated by the TPS.
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Abdollahi S, Dayyani M, Hoseinian-Azghadi E, Miri-Hakimabad H, Rafat-Motavalli L. A revised dosimetric characterization of 60Co BEBIG source: From single-source data to clinical dose distribution. Brachytherapy 2018; 17:1011-1022. [PMID: 30227978 DOI: 10.1016/j.brachy.2018.08.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 08/03/2018] [Accepted: 08/15/2018] [Indexed: 02/06/2023]
Abstract
PURPOSE Although the dosimetric characterization of 60Co BEBIG source can be found in several literature studies, the data sets show major discrepancies and the lack of uncertainty analyses. This study tried to determine an accurate dosimetric data set for this source using Monte Carlo (MC) simulations along with detailed uncertainty analysis. To explore how different dosimetric data sets can make changes in practical situations, clinical dose distributions based on our results were compared with the dose distributions derived from Granero et al. and consensus data sets. METHODS AND MATERIALS The MC simulations were performed with Monte Carlo N-Particle eXtended code (MCNPX) version 2.6.0 and the TG-43 parameters were estimated adhering to the American Association of Physicists in Medicine (AAPM) and European SocieTy for Radiotherapy and Oncology (ESTRO) 229 report. The dose rate distributions for single-source and two typical clinical cases, including one intracavitary and one interstitial, were calculated using an in-house code on the basis of the TG-43 formalism. RESULTS The total uncertainties for water dose rate on source transverse axis at 1 cm and 5 cm, air kerma strength, and dose rate constant were evaluated to be 0.10%, 0.09%, 0.04%, and 0.11%, respectively. Meaningful differences were found for the interstitial case in which 22% of clinical target volume (CTV) showed differences from ±1% to ±10% or even larger. CONCLUSIONS The MC uncertainty was derived about 16 times smaller than the typical MC component stated in TG-138, partly because of large number of histories and partly because the spectra of 60Co and also its photons' attenuation coefficients are adequately accurate. The results showed that in the clinical situations, the applicator geometry and the superposition of single-source dose distributions can reduce the differences observed between several data sets.
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Affiliation(s)
- Sara Abdollahi
- Medical Physics Department, Reza Radiotherapy and Oncology Center, Mashhad, Iran
| | - Mahdieh Dayyani
- Radiation Oncology Department, Reza Radiotherapy and Oncology Center, Mashhad, Iran
| | | | - Hashem Miri-Hakimabad
- Physics Department, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Laleh Rafat-Motavalli
- Physics Department, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran.
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Badry H, Oufni L, Ouabi H, Hirayama H. A Monte Carlo investigation of the dose distribution for 60Co high dose rate brachytherapy source in water and in different media. Appl Radiat Isot 2018; 136:104-110. [PMID: 29494942 DOI: 10.1016/j.apradiso.2018.02.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 02/11/2018] [Accepted: 02/14/2018] [Indexed: 10/18/2022]
Abstract
In this study, the dosimetric characterization for The BEBIG 60Co High Dose Rate (HDR) brachytherapy source model Co0.A86 was investigated and the validity of the EGS5 Monte Carlo code to reproduce the dosimetric parameters in water phantom was checked. In addition, the dose distribution for different tissue phantoms was calculated. The BEBIG 60Co HDR brachytherapy source was modeled using EGS5 Monte Carlo simulation code. A description of the source design, geometry and materials used in this work were provided. According to the update TG43-U1 formalism of AAPM, the air kerma strength, the dose rate constant, 2D rectangular dose distribution in water were calculated, moreover, the results of the radial dose function were obtained in water and different tissue phantoms; bone, lung, adipose tissue, breast and muscle. The obtained results were tabulated and presented in graphical formats for the comparison with available data. The calculated value of the air kerma strength of this study, 3.0419 U Bq-1, agree well with that of the other Monte Carlo calculation. The 2D look-up along-away rectangular dose were obtained in water, the results were similar to the published data for all distances larger than 1 cm, for the distances near to the source region on the transversal source axis small differences are apparent. The radial dose function were presented in graphical format for the comparison between the dose distribution in water and different tissue phantoms. The EGS5 results obtained in this study shows good consistency with the published data for the dosimetric parameters of the of the BEBIG 60Co HDR brachytherapy source. It seems that the radial dose function calculated in water differed in tissue phantoms due to the atomic composition and densities for media that are not taken account by the TG43-U1 formalism.
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Affiliation(s)
- Hamza Badry
- Sultan Moulay Slimane University, Faculty of Sciences and Techniques, Department of Physics (LPM-ERM), B.P. 523, 23000 Béni-Mellal, Morocco
| | - Lhoucine Oufni
- Sultan Moulay Slimane University, Faculty of Sciences and Techniques, Department of Physics (LPM-ERM), B.P. 523, 23000 Béni-Mellal, Morocco.
| | - Hmad Ouabi
- Oncology Center Al Azhar, Rabat, Morocco
| | - Hideo Hirayama
- Applied Research Laboratory, KEK, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
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Safigholi H, Meigooni AS, Song WY. Comparison of192Ir,169Yb, and60Co high-dose rate brachytherapy sources for skin cancer treatment. Med Phys 2017; 44:4426-4436. [DOI: 10.1002/mp.12335] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 04/18/2017] [Accepted: 04/23/2017] [Indexed: 02/06/2023] Open
Affiliation(s)
- Habib Safigholi
- Department of Medical Physics; Odette Cancer Centre; Sunnybrook Research Institute; Sunnybrook Hospital; University of Toronto; Toronto ON Canada
- Department of Electrical Engineering; Shiraz Branch; Islamic Azad University; Shiraz Iran
| | - Ali S. Meigooni
- School of Allied Health Science; University of Nevada Las Vegas (UNLV); Las Vegas NV USA
| | - William Y. Song
- Department of Medical Physics; Odette Cancer Centre; Sunnybrook Research Institute; Sunnybrook Hospital; University of Toronto; Toronto ON Canada
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Monte Carlo dosimetric characterization of the Flexisource Co-60 high-dose-rate brachytherapy source using PENELOPE. Brachytherapy 2017; 16:1073-1080. [PMID: 28669539 DOI: 10.1016/j.brachy.2017.04.245] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 04/20/2017] [Accepted: 04/26/2017] [Indexed: 11/21/2022]
Abstract
PURPOSE 60Co sources have been commercialized as an alternative to 192Ir sources for high-dose-rate (HDR) brachytherapy. One of them is the Flexisource Co-60 HDR source manufactured by Elekta. The only available dosimetric characterization of this source is that of Vijande et al. [J Contemp Brachytherapy 2012; 4:34-44], whose results were not included in the AAPM/ESTRO consensus document. In that work, the dosimetric quantities were calculated as averages of the results obtained with the Geant4 and PENELOPE Monte Carlo (MC) codes, though for other sources, significant differences have been quoted between the values obtained with these two codes. The aim of this work is to perform the dosimetric characterization of the Flexisource Co-60 HDR source using PENELOPE. METHODS AND MATERIALS The MC simulation code PENELOPE (v. 2014) has been used. Following the recommendations of the AAPM/ESTRO report, the radial dose function, the anisotropy function, the air-kerma strength, the dose rate constant, and the absorbed dose rate in water have been calculated. RESULTS The results we have obtained exceed those of Vijande et al. In particular, the absorbed dose rate constant is ∼0.85% larger. A similar difference is also found in the other dosimetric quantities. The effect of the electrons emitted in the decay of 60Co, usually neglected in this kind of simulations, is significant up to the distances of 0.25 cm from the source. CONCLUSIONS The systematic and significant differences we have found between PENELOPE results and the average values found by Vijande et al. point out that the dosimetric characterizations carried out with the various MC codes should be provided independently.
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Campos LT, de Almeida CEV. Monte Carlo Dosimetry of the 60Co BEBIG High Dose Rate for Brachytherapy. PLoS One 2015; 10:e0139032. [PMID: 26418559 PMCID: PMC4587958 DOI: 10.1371/journal.pone.0139032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 09/07/2015] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION The use of high-dose-rate brachytherapy is currently a widespread practice worldwide. The most common isotope source is 192Ir, but 60Co is also becoming available for HDR. One of main advantages of 60Co compared to 192Ir is the economic and practical benefit because of its longer half-live, which is 5.27 years. Recently, Eckert & Ziegler BEBIG, Germany, introduced a new afterloading brachytherapy machine (MultiSource®); it has the option to use either the 60Co or 192Ir HDR source. The source for the Monte Carlo calculations is the new 60Co source (model Co0.A86), which is referred to as the new BEBIG 60Co HDR source and is a modified version of the 60Co source (model GK60M21), which is also from BEBIG. OBJECTIVE AND METHODS The purpose of this work is to obtain the dosimetry parameters in accordance with the AAPM TG-43U1 formalism with Monte Carlo calculations regarding the BEBIG 60Co high-dose-rate brachytherapy to investigate the required treatment-planning parameters. The geometric design and material details of the source was provided by the manufacturer and was used to define the Monte Carlo geometry. To validate the source geometry, a few dosimetry parameters had to be calculated according to the AAPM TG-43U1 formalism. The dosimetry studies included the calculation of the air kerma strength Sk, collision kerma in water along the transverse axis with an unbounded phantom, dose rate constant and radial dose function. The Monte Carlo code system that was used was EGSnrc with a new cavity code, which is a part of EGS++ that allows calculating the radial dose function around the source. The spectrum to simulate 60Co was composed of two photon energies, 1.17 and 1.33 MeV. Only the gamma part of the spectrum was used; the contribution of the electrons to the dose is negligible because of the full absorption by the stainless-steel wall around the metallic 60Co. The XCOM photon cross-section library was used in subsequent simulations, and the photoelectric effect, pair production, Rayleigh scattering and bound Compton scattering were included in the simulation. Variance reduction techniques were used to speed up the calculation and to considerably reduce the computer time. The cut-off energy was 10 keV for electrons and photons. To obtain the dose rate distributions of the source in an unbounded liquid water phantom, the source was immersed at the center of a cube phantom of 100 cm3. The liquid water density was 0.998 g/cm3, and photon histories of up to 1010 were used to obtain the results with a standard deviation of less than 0.5% (k = 1). The obtained dose rate constant for the BEBIG 60Co source was 1.108±0.001 cGyh-1U-1, which is consistent with the values in the literature. The radial dose functions were compared with the values of the consensus data set in the literature, and they are consistent with the published data for this energy range.
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Affiliation(s)
- Luciana Tourinho Campos
- Laboratório de Ciências Radiológicas (LCR/DBB/ UERJ), Rua São Francisco Xavier, 524 Maracanã, CEP: 205550, Rio de Janeiro, Brasil
| | - Carlos Eduardo Veloso de Almeida
- Laboratório de Ciências Radiológicas (LCR/DBB/ UERJ), Rua São Francisco Xavier, 524 Maracanã, CEP: 205550, Rio de Janeiro, Brasil
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Guerrero R, Almansa JF, Torres J, Lallena AM. Dosimetric characterization of the 60Co BEBIG Co0.A86 high dose rate brachytherapy source using PENELOPE. Phys Med 2014; 30:960-7. [DOI: 10.1016/j.ejmp.2014.06.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 06/04/2014] [Accepted: 06/18/2014] [Indexed: 11/24/2022] Open
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EGSnrc Monte Carlo-aided dosimetric studies of the new BEBIG (60)Co HDR brachytherapy source. J Contemp Brachytherapy 2013; 5:148-56. [PMID: 24143150 PMCID: PMC3797406 DOI: 10.5114/jcb.2013.37419] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/25/2013] [Accepted: 09/26/2013] [Indexed: 11/17/2022] Open
Abstract
PURPOSE The purpose of this study is to obtain the dosimetric parameters of the new BEBIG (60)Co brachytherapy source following by TG-43U1 recommendation with appropriate electron cutoff energy (0.521 MeV). MATERIAL AND METHODS The new BEBIG (60)Co brachytherapy source is used to calculate the TG-43U1 parameters. EGSnrc-based Monte Carlo simulation code has been used to calculate the radial dose functions and anisotropy functions. 2D dose rate table is obtained with Cartesian coordinate system for surrounding the source. RESULTS The radial dose functions are calculated for the distance of 0.06 cm to 100 cm from the source center with different cutoff energies and compared. The anisotropy functions values are calculated with the range of 1° to 179°, and apart from 0.2 cm to 20 cm of radial distances. The along-away dose rate data are calculated for quality assurance purposes. The calculated values are compared with the consensus data set and previous published results. CONCLUSIONS The radial dose function values from 0.06 cm to 0.16 cm are low, and these values gradually increased up to 0.3 cm radial distance. The radial dose function values are compared with the values of consensus data set using EGSnrc code system, and it is in good agreement with the published data range. The data for < 0.1 cm is not available in consensus data set, and extrapolated value is included for 0 distances which is the same as the value of 0.1 cm. In this study, the obtained values are strictly fall-off to < 0.1 cm distances. Good agreement with the published data was observed, except the values less than 40° angle at 0.5 cm distance for anisotropy function values.
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Hannoun-Lévi JM, Peiffert D. [How to prepare the brachytherapy of the future]. Cancer Radiother 2013; 17:395-9. [PMID: 23993062 DOI: 10.1016/j.canrad.2013.06.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 05/27/2013] [Accepted: 06/07/2013] [Indexed: 11/26/2022]
Abstract
For more than a century, brachytherapy has been a treatment of choice for delivering a high dose in a small volume. However, over the past 15 years, this irradiation technique has stalled. Even so, brachytherapy allows the delivery of the right dose at the right place by dispensing with target volume motion and repositioning. The evolution of brachytherapy can be based on a road-map including at least the following three points: the acquisition of clinical evidence, teaching and valuation of the procedures. The evolution of brachytherapy will be also impacted by technological considerations (end of the production of low dose rate 192 iridium wires). Regarding the evolution toward a personalized treatment, brachytherapy of the future should take its place as a partner of other modern external beam radiation techniques, be performed by experimented actors (physicians, physicists, technicians, etc.) who received adequate training, and be valued in proportion to the delivered medical service.
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Affiliation(s)
- J-M Hannoun-Lévi
- Pôle de radiothérapie oncologique, centre Antoine-Lacassagne, 33, avenue de Valombrose, 06000 Nice, France; Université Nice-Sophia Antipolis, 06000 Nice, France.
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16
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Islam MA, Akramuzzaman MM, Zakaria GA. Dosimetric comparison between the microSelectron HDR (192)Ir v2 source and the BEBIG (60)Co source for HDR brachytherapy using the EGSnrc Monte Carlo transport code. J Med Phys 2013; 37:219-25. [PMID: 23293454 PMCID: PMC3532751 DOI: 10.4103/0971-6203.103608] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 08/14/2012] [Accepted: 10/08/2012] [Indexed: 11/11/2022] Open
Abstract
Manufacturing of miniaturized high activity 192Ir sources have been made a market preference in modern brachytherapy. The smaller dimensions of the sources are flexible for smaller diameter of the applicators and it is also suitable for interstitial implants. Presently, miniaturized 60Co HDR sources have been made available with identical dimensions to those of 192Ir sources. 60Co sources have an advantage of longer half life while comparing with 192Ir source. High dose rate brachytherapy sources with longer half life are logically pragmatic solution for developing country in economic point of view. This study is aimed to compare the TG-43U1 dosimetric parameters for new BEBIG 60Co HDR and new microSelectron 192Ir HDR sources. Dosimetric parameters are calculated using EGSnrc-based Monte Carlo simulation code accordance with the AAPM TG-43 formalism for microSlectron HDR 192Ir v2 and new BEBIG 60Co HDR sources. Air-kerma strength per unit source activity, calculated in dry air are 9.698×10-8 ± 0.55% U Bq-1 and 3.039×10-7 ± 0.41% U Bq-1 for the above mentioned two sources, respectively. The calculated dose rate constants per unit air-kerma strength in water medium are 1.116±0.12% cGy h-1U-1 and 1.097±0.12% cGy h-1U-1, respectively, for the two sources. The values of radial dose function for distances up to 1 cm and more than 22 cm for BEBIG 60Co HDR source are higher than that of other source. The anisotropic values are sharply increased to the longitudinal sides of the BEBIG 60Co source and the rise is comparatively sharper than that of the other source. Tissue dependence of the absorbed dose has been investigated with vacuum phantom for breast, compact bone, blood, lung, thyroid, soft tissue, testis, and muscle. No significant variation is noted at 5 cm of radial distance in this regard while comparing the two sources except for lung tissues. The true dose rates are calculated with considering photon as well as electron transport using appropriate cut-off energy. No significant advantages or disadvantages are found in dosimetric aspect comparing with two sources.
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Affiliation(s)
- M Anwarul Islam
- Department of Physics, Jahangirnagar University, Savar, Dhaka, Bangladesh
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17
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Bhola S, Selvam TP, Sridhar S, Vishwakarma RS. An analytic approach to the dosimetry of a new BEBIG (60)Co high-dose-rate brachytherapy source. J Med Phys 2012; 37:129-37. [PMID: 22973079 PMCID: PMC3437169 DOI: 10.4103/0971-6203.99228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 04/14/2012] [Accepted: 04/14/2012] [Indexed: 11/18/2022] Open
Abstract
We present a simple analytic tool for calculating the dose rate distribution in water for a new BEBIG high-dose-rate (HDR) (60)Co brachytherapy source. In the analytic tool, we consider the active source as a point located at the geometric center of the (60)Co material. The influence of the activity distribution in the active volume of the source is taken into account separately by use of the line source-based geometric function. The exponential attenuation of primary (60)Co photons by the source materials ((60)Co and stainless-steel) is included in the model. The model utilizes the point-source-based function, f(r) that represents the combined effect of the exponential attenuation and scattered photons in water. We derived this function by using the published radial dose function for a point (60)Co source in an unbounded water medium of radius 50 cm. The attenuation coefficients for (60)Co and the stainless-steel encapsulation materials are deduced as best-fit parameters that minimize the different.
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Affiliation(s)
- Subhalaxmi Bhola
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Anushaktinagar, Mumbai, India
| | - T. Palani Selvam
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Anushaktinagar, Mumbai, India
| | - Sahoo Sridhar
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Anushaktinagar, Mumbai, India
| | - Ramkrishna S. Vishwakarma
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Anushaktinagar, Mumbai, India
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Treatment planning study of the 3D dosimetric differences between Co-60 and Ir-192 sources in high dose rate (HDR) brachytherapy for cervix cancer. J Contemp Brachytherapy 2012; 4:52-9. [PMID: 23346140 PMCID: PMC3551368 DOI: 10.5114/jcb.2012.27952] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 02/24/2012] [Accepted: 03/19/2012] [Indexed: 11/17/2022] Open
Abstract
Purpose To evaluate whether Co-60 is equivalent to Ir-192 for HDR cervical brachytherapy, through 3D-DVH dose comparisons in standard and optimised plans. Previous studies have only considered 2D dosimetry, point dose comparisons or identical loading. Typical treatment times and economics are considered. Material and methods Plans were produced for eight cervix patients using Co-60 and Ir-192 sources, CT imaging and IU/two-channel-ring applicator (Eckert Ziegler BEBIG). The comparison was made under two conditions: (A) identical dwell positions and loading, prescribed to Point A and (B) optimised source dwells, prescribed to HR-CTV. This provided a direct comparison of inherent differences and residual differences under typical clinical plan optimisation. The DVH (target and OAR), ICRU reference points and isodose distributions were compared. Typical treatment times and source replacement costs were compared. Results Small differences (p < 0.01) in 3D dosimetry exist when using Co-60 compared to Ir-192, prescribed to Point A with identical loading patterns, particularly 3.3% increase in rectum D2cc. No significant difference was observed in this parameter when prescribing to the HR-CTV using dwell-time optimisation. There was no statistically significant difference in D90 between the two isotopes. Co-60 plans delivered consistently higher V150% (mean +4.4%, p = 0.03) and V400% (mean +11.6%, p < 0.01) compared to Ir-192 in optimised plans. Differences in physical source properties were overwhelmed by geometric effects. Conclusions Co-60 may be used as an effective alternative to Ir-192 for HDR cervix brachytherapy, producing similar plans of equivalent D90, but with logistical benefits. There is a small dose increase along the extension of the source axis when using Co-60 compared to Ir-192, leading to small rectal dose increases for identical loading patterns. This can be eliminated by planning optimisation techniques. Such optimisation may also be associated with increases in the overdose volume (V150-V400) with Co-60 compared to Ir-192.
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Monte Carlo dosimetric study of the Flexisource Co-60 high dose rate source. J Contemp Brachytherapy 2012; 4:34-44. [PMID: 23346138 PMCID: PMC3551374 DOI: 10.5114/jcb.2012.27950] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/23/2012] [Accepted: 02/23/2012] [Indexed: 11/20/2022] Open
Abstract
Purpose Recently, a new HDR 60Co brachytherapy source, Flexisource Co-60, has been developed (Nucletron B.V. Veenendaal, The Netherlands). This study aims to obtain dosimetric data for this source for its use in clinical practice as required by AAPM and ESTRO. Material and methods Two Monte Carlo radiation transport codes were used: Penelope2008 and GEANT4. The source was centrally-positioned in a 100 cm radius water phantom. Absorbed dose and collisional kerma were obtained using 0.01 cm (close) and 0.1 cm (far) sized voxels to provide high-resolution dosimetry near (far from) the source. Dose rate distributions obtained with the two Monte Carlo codes were compared. Results and Discussion Simulations performed with those two radiation transport codes showed an agreement typically within 0.2% for r > 0.8 cm and up to 2% closer to the source. Detailed results of dose distributions are being made available. Conclusions Dosimetric data are provided for the new Flexisource Co-60 source. These data are meant to be used in treatment planning systems in clinical practice.
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Chow JCL, Owrangi AM. Dependences of mucosal dose on photon beams in head-and-neck intensity-modulated radiation therapy: a Monte Carlo study. Med Dosim 2011; 37:195-200. [PMID: 21993201 DOI: 10.1016/j.meddos.2011.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/11/2011] [Accepted: 07/21/2011] [Indexed: 11/25/2022]
Abstract
Dependences of mucosal dose in the oral or nasal cavity on the beam energy, beam angle, multibeam configuration, and mucosal thickness were studied for small photon fields using Monte Carlo simulations (EGSnrc-based code), which were validated by measurements. Cylindrical mucosa phantoms (mucosal thickness = 1, 2, and 3 mm) with and without the bone and air inhomogeneities were irradiated by the 6- and 18-MV photon beams (field size = 1 × 1 cm(2)) with gantry angles equal to 0°, 90°, and 180°, and multibeam configurations using 2, 4, and 8 photon beams in different orientations around the phantom. Doses along the central beam axis in the mucosal tissue were calculated. The mucosal surface doses were found to decrease slightly (1% for the 6-MV photon beam and 3% for the 18-MV beam) with an increase of mucosal thickness from 1-3 mm, when the beam angle is 0°. The variation of mucosal surface dose with its thickness became insignificant when the beam angle was changed to 180°, but the dose at the bone-mucosa interface was found to increase (28% for the 6-MV photon beam and 20% for the 18-MV beam) with the mucosal thickness. For different multibeam configurations, the dependence of mucosal dose on its thickness became insignificant when the number of photon beams around the mucosal tissue was increased. The mucosal dose with bone was varied with the beam energy, beam angle, multibeam configuration and mucosal thickness for a small segmental photon field. These dosimetric variations are important to consider improving the treatment strategy, so the mucosal complications in head-and-neck intensity-modulated radiation therapy can be minimized.
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Affiliation(s)
- James C L Chow
- Department of Radiation Physics, Princess Margaret Hospital, Toronto, Ontario, Canada.
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Monte Carlo derivation of AAPM TG-43 dosimetric parameters for GZP6 Co-60 HDR sources. Phys Med 2011; 28:153-60. [PMID: 21624844 DOI: 10.1016/j.ejmp.2011.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 04/19/2011] [Accepted: 04/22/2011] [Indexed: 11/21/2022] Open
Abstract
Cobalt 60 source is generally available on high dose rate (HDR) afterloading equipment especially for treatment of gynecological lesions. The GZP6 remote afterloader (Nuclear Power Institute of China) utilizes (60)Co sources for treatment of intracavitary and intraluminal malignancies. In this study, the AAPM TG-43 dosimetric parameters of three sources in GZP6 system have been studied using MCNP4C Monte Carlo (MC) code; and the results are compared with other available (60)Co HDR sources. The presented parameters consist of air kerma strength, dose rate constant, radial dose function and anisotropy function. They show less than 1% uncertainty. The TG-43 based dosimetry data can be used not only to validate the dedicated treatment planning software (TPS), but also to introduce new complementary software to enhance the system performance in gynecological treatments.
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Selvam TP, Sahoo S, Vishwakarma RS. Comment on "Monte Carlo dosimetry of 60Co HDR brachytherapy sources" [Med. Phys. 30, 712-721 (2003)]. Med Phys 2010; 37:5146-7. [PMID: 20964234 DOI: 10.1118/1.3475939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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