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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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Jagodinsky JC, Medeiros G, Raj HH, Razuan A, Locsin A, Dempsey TG, Tang B, Chakravarty I, Clark PA, Sriramaneni RN, Jin WJ, Lan KH, Das RK, Miller JR, Suarez-Gonzalez D, Morris ZS. A multipurpose brachytherapy catheter to enable intratumoral injection. Brachytherapy 2021; 20:900-910. [PMID: 33785280 DOI: 10.1016/j.brachy.2020.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/16/2020] [Accepted: 10/23/2020] [Indexed: 11/30/2022]
Abstract
PURPOSE To create and test a multipurpose brachytherapy catheter prototype enabling intratumoral injection and brachytherapy after a single catheter insertion. METHODS AND MATERIALS The design of the prototype consists of an outer tube and an inner syringe tube that can be filled with injectable agent. The outer sheath and inner syringe tube were constructed using polytetrafluoroethylene tubing, and the other components were 3D printed using dental resin and polylactic acid material. To demonstrate functionality, we injected in vitro phantoms with dyed saline. For proof of concept, we demonstrated the potential for the prototype to deliver cell therapy, enhance tumor delineation, deliver tattoo ink for pathology marking, avoid toxicity through local delivery of chemotherapy, and facilitate combination brachytherapy and immunotherapy. RESULTS The prototype enables accurate injection in vitro and in vivo without altering dosimetry. To illustrate the potential for delivery of cell therapies, we injected luciferase-expressing splenocytes and confirmed their delivery with bioluminescence imaging. To demonstrate feasibility of radiographically visualizing injected material, we delivered iohexol contrast intratumorally and confirmed tumor retention using Faxitron x-ray imaging. In addition, we show the potential of intratumoral administration to reduce toxicity associated with cyclophosphamide compared with systemic administration. To demonstrate feasibility, we treated tumor-bearing mice with brachytherapy (192Ir source, 2 Gy to 5 mm) in combination with intratumoral injection of 375,000 U of interleukin 2 and observed no increased toxicity. CONCLUSIONS These results demonstrate that a prototype multipurpose brachytherapy catheter enables accurate intratumoral injection and support the feasibility of combining intratumoral injection with brachytherapy.
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Affiliation(s)
- Justin C Jagodinsky
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
| | - Gabriella Medeiros
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Hayley H Raj
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Amira Razuan
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Alexis Locsin
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Tirhas G Dempsey
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Beixiao Tang
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Ishan Chakravarty
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Paul A Clark
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Raghava N Sriramaneni
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Won Jong Jin
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Keng-Hsueh Lan
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Rupak K Das
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Jessica R Miller
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Darilis Suarez-Gonzalez
- Department of Biomedical Engineering, College of Engineering, University of Wisconsin-Madison, Madison, WI
| | - Zachary S Morris
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI
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Dosimetric investigation of a new high dose rate 192Ir brachytherapy source, IRAsource, by Monte Carlo method. Rep Pract Oncol Radiother 2020; 25:139-145. [PMID: 32051681 DOI: 10.1016/j.rpor.2019.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 11/11/2019] [Accepted: 12/23/2019] [Indexed: 11/23/2022] Open
Abstract
Purpose The purpose of the present study was to perform an independent calculation of dosimetric parameters associated with a new 192Ir brachytherapy source model, IRAsource. Materials and methods The parameters of air kerma strength (AKS), dose rate constant (DRC), geometry function (GF), radial dose function (RDF), as well as two-dimensional (2D) anisotropy function (AF) of IRAsource 192Ir source model were calculated in this study. The MC n-particle extended (MCNPX) code was also employed for simulating high dose rate (HDR), IRAsource and 192Ir source; and formalism was used for calculating dosimetry parameters based on task group number 43 updated report (TG-43 U1). Results The results of this study were consistent with the ones reported about the IRAsource source by Sarabiasl et al. The AKS per 1 mCi activity and the DRC values were also equal to 3.65 cGycm2 h-1 mCi-1 and 1.094 cGyh-1U-1; respectively. The comparison of the results of the DRC and the RDF reported by Sarabiasl et al. also validated the 192Ir IRAsource simulation in this study. Moreover, the AFs of IRAsource source model were in a good agreement with those of Sarabiasl et al. at different distances, which could be attributed to identical geometries. Conclusion In line with those reported by Sarabiasl et al., the results of this study confirmed the IRAsource 192Ir source for clinical uses. The calculated dosimetric parameters of the IRAsource source could be utilized in clinical practices as input data sets or for validation of treatment planning system calculations.
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Campos LT, Magalhães LAG, de Almeida CEV. Determination of a beam quality conversion factor from 60Co to 192Ir. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2019. [DOI: 10.1016/j.jrras.2018.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Luciana Tourinho Campos
- Laboratório de Ciências Radiológicas (LCR/DBB/ UERJ), Rua São Francisco Xavier, 524 Maracanã, Rio de Janeiro, CEP: 205550, Brazil
- Departamento de Física Aplicada e Termodinâmica (DFAT/UERJ), Rua São Francisco Xavier, 524 Maracanã, Rio de Janeiro, CEP: 205550, Brazil
| | | | - Carlos Eduardo Veloso de Almeida
- Laboratório de Ciências Radiológicas (LCR/DBB/ UERJ), Rua São Francisco Xavier, 524 Maracanã, Rio de Janeiro, CEP: 205550, Brazil
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Determination of the dose enhancement exclusively in tumor tissue due to the presence of GNPs. Appl Radiat Isot 2019; 145:39-46. [DOI: 10.1016/j.apradiso.2018.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 11/04/2018] [Accepted: 11/24/2018] [Indexed: 11/21/2022]
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Comparison of the hypothetical (57)Co brachytherapy source with the (192)Ir source. Contemp Oncol (Pozn) 2016; 20:327-34. [PMID: 27688731 PMCID: PMC5032162 DOI: 10.5114/wo.2016.61854] [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: 04/06/2015] [Accepted: 11/30/2015] [Indexed: 11/17/2022] Open
Abstract
Aim of the study The 57Co radioisotope has recently been proposed as a hypothetical brachytherapy source due to its high specific activity, appropriate half-life (272 days) and medium energy photons (114.17 keV on average). In this study, Task Group No. 43 dosimetric parameters were calculated and reported for a hypothetical 57Co source. Material and methods A hypothetical 57Co source was simulated in MCNPX, consisting of an active cylinder with 3.5 mm length and 0.6 mm radius encapsulated in a stainless steel capsule. Three photon energies were utilized (136 keV [10.68%], 122 keV [85.60%], 14 keV [9.16%]) for the 57Co source. Air kerma strength, dose rate constant, radial dose function, anisotropy function, and isodose curves for the source were calculated and compared to the corresponding data for a 192Ir source. Results The results are presented as tables and figures. Air kerma strength per 1 mCi activity for the 57Co source was 0.46 cGyh–1 cm 2 mCi–1. The dose rate constant for the 57Co source was determined to be 1.215 cGyh–1U–1. The radial dose function for the 57Co source has an increasing trend due to multiple scattering of low energy photons. The anisotropy function for the 57Co source at various distances from the source is more isotropic than the 192Ir source. Conclusions The 57Co source has advantages over 192Ir due to its lower energy photons, longer half-life, higher dose rate constant and more isotropic anisotropic function. However, the 192Ir source has a higher initial air kerma strength and more uniform radial dose function. These properties make 57Co a suitable source for use in brachytherapy applications.
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Ghorbani M, Mehrpouyan M, Davenport D, Ahmadi Moghaddas T. Effect of photon energy spectrum on dosimetric parameters of brachytherapy sources. Radiol Oncol 2016; 50:238-46. [PMID: 27247558 PMCID: PMC4852960 DOI: 10.1515/raon-2016-0019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/29/2016] [Indexed: 11/15/2022] Open
Abstract
AIM The aim of this study is to quantify the influence of the photon energy spectrum of brachytherapy sources on task group No. 43 (TG-43) dosimetric parameters. BACKGROUND Different photon spectra are used for a specific radionuclide in Monte Carlo simulations of brachytherapy sources. MATERIALS AND METHODS MCNPX code was used to simulate 125I, 103Pd, 169Yb, and 192Ir brachytherapy sources. Air kerma strength per activity, dose rate constant, radial dose function, and two dimensional (2D) anisotropy functions were calculated and isodose curves were plotted for three different photon energy spectra. The references for photon energy spectra were: published papers, Lawrence Berkeley National Laboratory (LBNL), and National Nuclear Data Center (NNDC). The data calculated by these photon energy spectra were compared. RESULTS Dose rate constant values showed a maximum difference of 24.07% for 103Pd source with different photon energy spectra. Radial dose function values based on different spectra were relatively the same. 2D anisotropy function values showed minor differences in most of distances and angles. There was not any detectable difference between the isodose contours. CONCLUSIONS Dosimetric parameters obtained with different photon spectra were relatively the same, however it is suggested that more accurate and updated photon energy spectra be used in Monte Carlo simulations. This would allow for calculation of reliable dosimetric data for source modeling and calculation in brachytherapy treatment planning systems.
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Affiliation(s)
- Mahdi Ghorbani
- Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Mehrpouyan
- Bioinformatics Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - David Davenport
- Comprehensive Cancer Centers of Nevada, Las Vegas, Nevada, USA
| | - Toktam Ahmadi Moghaddas
- Department of Basic Medical Sciences, Neyshabur University of Medical Sciences, Neyshabur, Iran
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Ghorbani M, Hashempour M, Azizi M, Meigooni AS. Evaluating the effect of various intracavitary applicators on dosimetric parameters of 192Ir, 137Cs, and 60Co sources. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2016; 39:477-91. [DOI: 10.1007/s13246-016-0441-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 03/30/2016] [Indexed: 01/08/2023]
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Reyes E, Sosa M, Gil-Villegas A, Monzón E. Monte Carlo characterization of the GammaMed HDR Plus Ir-192 brachytherapy source. Biomed Phys Eng Express 2016. [DOI: 10.1088/2057-1976/2/1/015017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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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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Ho Than MT, Munro Iii JJ, Medich DC. Dosimetric characterization of the M-15 high-dose-rate Iridium-192 brachytherapy source using the AAPM and ESTRO formalism. J Appl Clin Med Phys 2015; 16:5270. [PMID: 26103489 PMCID: PMC5690138 DOI: 10.1120/jacmp.v16i3.5270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 12/16/2014] [Accepted: 01/16/2015] [Indexed: 11/23/2022] Open
Abstract
The Source Production & Equipment Co. (SPEC) model M−15 is a new Iridium−192 brachytherapy source model intended for use as a temporary high‐dose‐rate (HDR) brachytherapy source for the Nucletron microSelectron Classic afterloading system. The purpose of this study is to characterize this HDR source for clinical application by obtaining a complete set of Monte Carlo calculated dosimetric parameters for the M‐15, as recommended by AAPM and ESTRO, for isotopes with average energies greater than 50 keV. This was accomplished by using the MCNP6 Monte Carlo code to simulate the resulting source dosimetry at various points within a pseudoinfinite water phantom. These dosimetric values next were converted into the AAPM and ESTRO dosimetry parameters and the respective statistical uncertainty in each parameter also calculated and presented. The M−15 source was modeled in an MCNP6 Monte Carlo environment using the physical source specifications provided by the manufacturer. Iridium−192 photons were uniformly generated inside the iridium core of the model M−15 with photon and secondary electron transport replicated using photoatomic cross‐sectional tables supplied with MCNP6. Simulations were performed for both water and air/vacuum computer models with a total of 4×109 sources photon history for each simulation and the in‐air photon spectrum filtered to remove low‐energy photons below δ=10%keV. Dosimetric data, including D(r,θ),gL(r),F(r,θ),Φan(r), and φ¯an, and their statistical uncertainty were calculated from the output of an MCNP model consisting of an M−15 source placed at the center of a spherical water phantom of 100 cm diameter. The air kerma strength in free space, SK, and dose rate constant, Λ, also was computed from a MCNP model with M−15Iridium−192 source, was centered at the origin of an evacuated phantom in which a critical volume containing air at STP was added 100 cm from the source center. The reference dose rate, D˙(r0,θ0)≡D˙(1cm,π/2), is found to be 4.038±0.064 cGy mCi−1 h−1. The air kerma strength, SK, is reported to be 3.632±0.086 cGy cm2 mCi−1 g−1, and the dose rate constant, Λ, is calculated to be 1.112±0.029 cGy h−1 U−1. The normalized dose rate, radial dose function, and anisotropy function with their uncertainties were computed and are represented in both tabular and graphical format in the report. A dosimetric study was performed of the new M−15Iridium−192 HDR brachytherapy source using the MCNP6 radiation transport code. Dosimetric parameters, including the dose‐rate constant, radial dose function, and anisotropy function, were calculated in accordance with the updated AAPM and ESTRO dosimetric parameters for brachytherapy sources of average energy greater than 50 keV. These data therefore may be applied toward the development of a treatment planning program and for clinical use of the source. PACS numbers: 87.56.bg, 87.53.Jw
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Effect of tissue composition on dose distribution in brachytherapy with various photon emitting sources. J Contemp Brachytherapy 2014; 6:54-67. [PMID: 24790623 PMCID: PMC4003431 DOI: 10.5114/jcb.2014.42024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 03/01/2014] [Accepted: 03/28/2014] [Indexed: 11/23/2022] Open
Abstract
Purpose The aim of this study is to compare the dose in various soft tissues in brachytherapy with photon emitting sources. Material and methods 103Pd, 125I, 169Yb, 192Ir brachytherapy sources were simulated with MCNPX Monte Carlo code, and their dose rate constant and radial dose function were compared with the published data. A spherical phantom with 50 cm radius was simulated and the dose at various radial distances in adipose tissue, breast tissue, 4-component soft tissue, brain (grey/white matter), muscle (skeletal), lung tissue, blood (whole), 9-component soft tissue, and water were calculated. The absolute dose and relative dose difference with respect to 9-component soft tissue was obtained for various materials, sources, and distances. Results There was good agreement between the dosimetric parameters of the sources and the published data. Adipose tissue, breast tissue, 4-component soft tissue, and water showed the greatest difference in dose relative to the dose to the 9-component soft tissue. The other soft tissues showed lower dose differences. The dose difference was also higher for 103Pd source than for 125I, 169Yb, and 192Ir sources. Furthermore, greater distances from the source had higher relative dose differences and the effect can be justified due to the change in photon spectrum (softening or hardening) as photons traverse the phantom material. Conclusions The ignorance of soft tissue characteristics (density, composition, etc.) by treatment planning systems incorporates a significant error in dose delivery to the patient in brachytherapy with photon sources. The error depends on the type of soft tissue, brachytherapy source, as well as the distance from the source.
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Currier B, Munro JJ, Medich DC. Dosimetric characterization of the GammaClip™ 169Yb low dose rate permanent implant brachytherapy source for the treatment of nonsmall cell lung cancer postwedge resection. Med Phys 2014; 40:080701. [PMID: 23927294 DOI: 10.1118/1.4812675] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE A novel (169)Yb low dose rate permanent implant brachytherapy source, the GammaClip™, was developed by Source Production & Equipment Co. (New Orleans, LA) which is designed similar to a surgical staple while delivering therapeutic radiation. In this report, the brachytherapy source was characterized in terms of "Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: Report of the AAPM and ESTRO" by Perez-Calatayud et al. [Med. Phys. 39, 2904-2929 (2012)] using the updated AAPM Task Group Report No. 43 formalism. METHODS Monte Carlo calculations were performed using Monte Carlo N-Particle 5, version 1.6 in water and air, the in-air photon spectrum filtered to remove photon energies below 10 keV in accordance with TG-43U1 recommendations and previously reviewed (169)Yb energy cutoff levels [D. C. Medich, M. A. Tries, and J. M. Munro, "Monte Carlo characterization of an Ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty," Med. Phys. 33, 163-172 (2006)]. TG-43U1 dosimetric data, including SK, Ḋ(r,θ), Λ, gL(r), F(r, θ), φan(r), and φan were calculated along with their statistical uncertainties. Since the source is not axially symmetric, an additional set of calculations were performed to assess the resulting axial anisotropy. RESULTS The brachytherapy source's dose rate constant was calculated to be (1.22±0.03) cGy h(-1) U(-1). The uncertainty in the dose to water calculations, Ḋ(r,θ), was determined to be 2.5%, dominated by the uncertainties in the cross sections. The anisotropy constant, φan, was calculated to be 0.960±0.011 and was obtained by integrating the anisotropy factor between 1 and 10 cm using a weighting factor proportional to r(-2). The radial dose function was calculated at distances between 0.5 and 12 cm, with a maximum value of 1.20 at 5.15±0.03 cm. Radial dose values were fit to a fifth order polynomial and dual exponential regression. Since the source is not axially symmetric, angular Monte Carlo calculations were performed at 1 cm which determined that the maximum azimuthal anisotropy was less than 8%. CONCLUSIONS With a higher photon energy, shorter half-life and higher initial dose rate 169Yb is an interesting alternative to 125I for the treatment of nonsmall cell lung cancer.
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Bahreyni Toossi MT, Ghorbani M, Mehrpouyan M, Akbari F, Sobhkhiz Sabet L, Soleimani Meigooni A. A Monte Carlo study on tissue dose enhancement in brachytherapy: a comparison between gadolinium and gold nanoparticles. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2012; 35:177-85. [PMID: 22700179 DOI: 10.1007/s13246-012-0143-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 05/21/2012] [Indexed: 11/30/2022]
Abstract
The aim of this study was to quantify the dose enhancement by gadolinium and gold nanoparticles in brachytherapy. MCNPX Monte Carlo code was used to simulate four brachytherapy sources: (60)Co, (198)Au, (192)Ir, (169)Yb. To verify the accuracy of our simulations, the obtained values of dose rate constants and radial dose functions were compared with corresponding published values for these sources. To study dose enhancements, a spherical soft tissue phantom with 15 cm in radius was simulated. Gadolinium and gold nanoparticles at 10, 20 and 30 mg/ml concentrations were separately assumed in a 1 × 1 × 1 cm(3) volume simulating tumour. The simulated dose to the tumour with the impurity was compared to the dose without impurity, as a function of radial distance and concentration of the impurity, to determine the enhancement of dose due to the presence of the impurity. Dose enhancements in the tumour obtained in the presence of gadolinium and gold nanoparticles with concentration of 30 mg/ml, were found to be in the range of -0.5-106.1 and 0.4-153.1 % respectively. In addition, at higher radial distances from the source center, higher dose enhancements were observed. GdNPs can be used as a high atomic number material to enhance dose in tumour volume with dose enhancements up to 106.1 % when used in brachytherapy. Regardless considering the clinical limitations of the here-in presented model, for a similar source and concentration of nanoparticles, gold nanoparticles show higher dose enhancement than gadolinium nanoparticles and can have more clinical usefulness as dose enhancer material.
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Kumar S, Srinivasan P, Sharma SD, Mayya YS. A simplified analytical approach to estimate the parameters required for strength determination of HDR 192Ir brachytherapy sources using a Farmer-type ionization chamber. Appl Radiat Isot 2011; 70:282-9. [PMID: 21872480 DOI: 10.1016/j.apradiso.2011.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 06/29/2011] [Accepted: 08/06/2011] [Indexed: 01/10/2023]
Abstract
Measuring the strength of high dose rate (HDR) (192)Ir brachytherapy sources on receipt from the vendor is an important component of a quality assurance program. Owing to their ready availability in radiotherapy departments, the Farmer-type ionization chambers are also used to determine the strength of HDR (192)Ir brachytherapy sources. The use of a Farmer-type ionization chamber requires the estimation of the scatter correction factor along with positioning error (c) and the constant of proportionality (f) to determine the strength of HDR (192)Ir brachytherapy sources. A simplified approach based on a least squares method was developed for estimating the values of f and M(s). The seven distance method was followed to record the ionization chamber readings for parameterization of f and M(s). Analytically calculated values of M(s) were used to determine the room scatter correction factor (K(sc)). The Monte Carlo simulations were also carried out to calculate f and K(sc) to verify the magnitude of the parameters determined by the proposed analytical approach. The value of f determined using the simplified analytical approach was found to be in excellent agreement with the Monte Carlo simulated value (within 0.7%). Analytically derived values of K(sc) were also found to be in good agreement with the Monte Carlo calculated values (within 1.47%). Being far simpler than the presently available methods of evaluating f, the proposed analytical approach can be adopted for routine use by clinical medical physicists to estimate f by hand calculations.
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Affiliation(s)
- Sudhir Kumar
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, CTCRS, Anushaktinagar, Mumbai 400094, India
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Patel NP, Majumdar B, Vijayan V. Comparative dosimetry of GammaMed Plus high-dose rate Ir brachytherapy source. J Med Phys 2010; 35:137-43. [PMID: 20927220 PMCID: PMC2936182 DOI: 10.4103/0971-6203.66761] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 12/18/2009] [Accepted: 03/25/2010] [Indexed: 11/04/2022] Open
Abstract
The comparative dosimetry of GammaMed (GM) Plus high-dose rate brachytherapy source was performed by an experiment using 0.1-cc thimble ionization chamber and simulation-based study using EGSnrc code. In-water dose measurements were performed with 0.1-cc chamber to derive the radial dose function (r = 0.8 to 20.0 cm) and anisotropy function (r = 5.0 cm with polar angle from 10° to 170°). The nonuniformity correction factor for 0.1-cc chamber was applied for in-water measurements at shorter distances from the source. The EGSnrc code was used to derive the dose rate constant (Λ), radial dose function g(L)(r) and anisotropy function F(r, θ) of GM Plus source. The dosimetric data derived using EGSnrc code in our study were in very good agreement relative to published data for GM Plus source. The radial dose function up to 12 cm derived from measured dose using 0.1-cc chamber was in agreement within ±3% of data derived by the simulation study.
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Affiliation(s)
- N P Patel
- Department of Physics, Govt. College of Science, Raipur; India
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Cazeca MJ, Medich DC, Munro JJ. Effects of breast-air and breast-lung interfaces on the dose rate at the planning target volume of a MammoSite®
catheter for Yb-169 and Ir-192 HDR sources. Med Phys 2010; 37:4038-45. [DOI: 10.1118/1.3458720] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Yi CY, Chun KJ, Hah SH, Kim HM, Lim C. Dosimetry parameters of the IRH10 192Ir high dose rate brachytherapy source. JOURNAL OF RADIATION RESEARCH 2010; 51:485-492. [PMID: 20508393 DOI: 10.1269/jrr.09102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The dosimetry parameters of the IRH10 (192)Ir high dose rate brachytherapy source were obtained from the dose calculation formalism recommended in the AAPM Task Group No. 43 report using the Monte Carlo code PENELOPE. The absorbed doses to water and air originating from the photons of the IRH10 (192)Ir brachytherapy source were calculated by the collision kerma approximation. The dose rate constant was evaluated to be (1.110 +/- 0.011) cGy/h U(-1). The dose rate per unit air kerma strength around the (192)Ir IRH10 brachytherapy source and the anisotropy function were given in tables and figures.
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Affiliation(s)
- Chul-Young Yi
- Center for Ionizing Radiation, Korea Research Institute of Standards and Science, Yuseong-Gu, Daejeon, Korea.
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Medich DC, Munro JJ. Dependence of Yb-169 absorbed dose energy correction factors on self-attenuation in source material and photon buildup in water. Med Phys 2010; 37:2135-44. [DOI: 10.1118/1.3372291] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Evaluation of interpolation methods for TG-43 dosimetric parameters based on comparison with Monte Carlo data for high-energy brachytherapy sources. J Contemp Brachytherapy 2010; 2:28-32. [PMID: 28031740 PMCID: PMC5183640 DOI: 10.5114/jcb.2010.13715] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 03/02/2010] [Indexed: 12/02/2022] Open
Abstract
Purpose The aim of this work was to determine dose distributions for high-energy brachytherapy sources at spatial locations not included in the radial dose function gL(r) and 2D anisotropy function F(r,θ) table entries for radial distance r and polar angle θ. The objectives of this study are as follows: 1) to evaluate interpolation methods in order to accurately derive gL(r) and F(r,θ) from the reported data; 2) to determine the minimum number of entries in gL(r) and F(r,θ) that allow reproduction of dose distributions with sufficient accuracy. Material and methods Four high-energy photon-emitting brachytherapy sources were studied: 60Co model Co0.A86, 137Cs model CSM-3, 192Ir model Ir2.A85-2, and 169Yb hypothetical model. The mesh used for r was: 0.25, 0.5, 0.75, 1, 1.5, 2–8 (integer steps) and 10 cm. Four different angular steps were evaluated for F(r,θ): 1°, 2°, 5° and 10°. Linear-linear and logarithmic-linear interpolation was evaluated for gL(r). Linear-linear interpolation was used to obtain F(r,θ) with resolution of 0.05 cm and 1°. Results were compared with values obtained from the Monte Carlo (MC) calculations for the four sources with the same grid. Results Linear interpolation of gL(r) provided differences ≤ 0.5% compared to MC for all four sources. Bilinear interpolation of F(r,θ) using 1° and 2° angular steps resulted in agreement ≤ 0.5% with MC for 60Co, 192Ir, and 169Yb, while 137Cs agreement was ≤ 1.5% for θ < 15°. Conclusions The radial mesh studied was adequate for interpolating gL(r) for high-energy brachytherapy sources, and was similar to commonly found examples in the published literature. For F(r,θ) close to the source longitudinal-axis, polar angle step sizes of 1°-2° were sufficient to provide 2% accuracy for all sources.
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Cazeca MJ, Medich DC, Munro JJ. Monte Carlo characterization of a new Yb-169 high dose rate source for brachytherapy application. Med Phys 2010; 37:1129-36. [DOI: 10.1118/1.3301607] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Taylor REP, Rogers DWO. EGSnrc Monte Carlo calculated dosimetry parameters for Ir192 and Yb169 brachytherapy sources. Med Phys 2008; 35:4933-44. [DOI: 10.1118/1.2987676] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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