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Safigholi H, Chamberland MJP, Taylor REP, Allen CH, Martinov MP, Rogers DWO, Thomson RM. Update of the CLRP TG‐43 parameter database for low‐energy brachytherapy sources. Med Phys 2020; 47:4656-4669. [DOI: 10.1002/mp.14249] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/08/2020] [Accepted: 05/05/2020] [Indexed: 12/23/2022] Open
Affiliation(s)
- Habib Safigholi
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - Marc J. P. Chamberland
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - Randle E. P. Taylor
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - Christian H. Allen
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - Martin P. Martinov
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - D. W. O. Rogers
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
| | - Rowan M. Thomson
- Carleton Laboratory for Radiotherapy Physics (CLRP) Department of Physics Carleton University Ottawa ON K1S 5B6 Canada
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Zaker N, Zehtabian M, Sina S, Koontz C, Meigooni AS. Comparison of TG-43 dosimetric parameters of brachytherapy sources obtained by three different versions of MCNP codes. J Appl Clin Med Phys 2016; 17:379-390. [PMID: 27074460 PMCID: PMC5874963 DOI: 10.1120/jacmp.v17i2.5797] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 11/09/2015] [Accepted: 11/03/2015] [Indexed: 11/23/2022] Open
Abstract
Monte Carlo simulations are widely used for calculation of the dosimetric parameters of brachytherapy sources. MCNP4C2, MCNP5, MCNPX, EGS4, EGSnrc, PTRAN, and GEANT4 are among the most commonly used codes in this field. Each of these codes utilizes a cross-sectional library for the purpose of simulating different elements and materials with complex chemical compositions. The accuracies of the final outcomes of these simulations are very sensitive to the accuracies of the cross-sectional libraries. Several investigators have shown that inaccuracies of some of the cross section files have led to errors in 125I and 103Pd parameters. The purpose of this study is to compare the dosimetric parameters of sample brachytherapy sources, calculated with three different versions of the MCNP code - MCNP4C, MCNP5, and MCNPX. In these simulations for each source type, the source and phantom geometries, as well as the number of the photons, were kept identical, thus eliminating the possible uncertainties. The results of these investigations indicate that for low-energy sources such as 125I and 103Pd there are discrepancies in gL(r) values. Discrepancies up to 21.7% and 28% are observed between MCNP4C and other codes at a distance of 6 cm for 103Pd and 10 cm for 125I from the source, respectively. However, for higher energy sources, the discrepancies in gL(r) values are less than 1.1% for 192Ir and less than 1.2% for 137Cs between the three codes.
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Rodriguez M, Rogers DWO. Effect of improved TLD dosimetry on the determination of dose rate constants for (125)I and (103)Pd brachytherapy seeds. Med Phys 2015; 41:114301. [PMID: 25370677 DOI: 10.1118/1.4895003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
PURPOSE To more accurately account for the relative intrinsic energy dependence and relative absorbed-dose energy dependence of TLDs when used to measure dose rate constants (DRCs) for (125)I and (103)Pd brachytherapy seeds, to thereby establish revised "measured values" for all seeds and compare the revised values with Monte Carlo and consensus values. METHODS The relative absorbed-dose energy dependence, f(rel), for TLDs and the phantom correction, Pphant, are calculated for (125)I and (103)Pd seeds using the EGSnrc BrachyDose and DOSXYZnrc codes. The original energy dependence and phantom corrections applied to DRC measurements are replaced by calculated (f(rel))(-1) and Pphant values for 24 different seed models. By comparing the modified measured DRCs to the MC values, an appropriate relative intrinsic energy dependence, kbq (rel), is determined. The new Pphant values and relative absorbed-dose sensitivities, SAD (rel), calculated as the product of (f(rel))(-1) and (kbq (rel))(-1), are used to individually revise the measured DRCs for comparison with Monte Carlo calculated values and TG-43U1 or TG-43U1S1 consensus values. RESULTS In general, f(rel) is sensitive to the energy spectra and models of the brachytherapy seeds. Values may vary up to 8.4% among (125)I and (103)Pd seed models and common TLD shapes. Pphant values depend primarily on the isotope used. Deduced (kbq (rel))(-1) values are 1.074 ± 0.015 and 1.084 ± 0.026 for (125)I and (103)Pd seeds, respectively. For (1 mm)(3) chips, this implies an overall absorbed-dose sensitivity relative to (60)Co or 6 MV calibrations of 1.51 ± 1% and 1.47 ± 2% for (125)I and (103)Pd seeds, respectively, as opposed to the widely used value of 1.41. Values of Pphant calculated here have much lower statistical uncertainties than literature values, but systematic uncertainties from density and composition uncertainties are significant. Using these revised values with the literature's DRC measurements, the average discrepancies between revised measured values and Monte Carlo values are 1.2% and 0.2% for (125)I and (103)Pd seeds, respectively, compared to average discrepancies for the original measured values of 4.8%. On average, the revised measured values are 4.3% and 5.9% lower than the original measured values for (103)Pd and (125)I seeds, respectively. The average of revised DRCs and Monte Carlo values is 3.8% and 2.8% lower for (125)I and (103)Pd seeds, respectively, than the consensus values in TG-43U1 or TG-43U1S1. CONCLUSIONS This work shows that f(rel) is TLD shape and seed model dependent suggesting a need to update the generalized energy response dependence, i.e., relative absorbed-dose sensitivity, measured 25 years ago and applied often to DRC measurements of (125)I and (103)Pd brachytherapy seeds. The intrinsic energy dependence for LiF TLDs deduced here is consistent with previous dosimetry studies and emphasizes the need to revise the DRC consensus values reported by TG-43U1 or TG-43U1S1.
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Affiliation(s)
- M Rodriguez
- Carleton Laboratory for Radiotherapy Physics, Carleton University, Ottawa, Ontario K1S 5B6, Canada and Princess Margaret Hospital, Toronto, Ontario M5G 2M9, Canada
| | - D W O Rogers
- Carleton Laboratory for Radiotherapy Physics, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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Teles P, Barros S, Cardoso S, Facure A, da Rosa LAR, Santos M, Pereira P, Vaz P, Zankl M. A dosimetric study of prostate brachytherapy using Monte Carlo simulations with a voxel phantom, measurements and a comparison with a treatment planning procedure. RADIATION PROTECTION DOSIMETRY 2015; 165:482-487. [PMID: 25870437 DOI: 10.1093/rpd/ncv055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In prostate brachytherapy treatments, there is an initial swelling of the prostate of the patient due to an oedema related to the insertion of the seeds. The variation of the prostate volume can lead to variations in the final prescribed dose in treatment planning procedures. As such, it is important to understand their influence for dose optimisation purposes. This work reports on a dosimetric study of the swelling of the prostate in prostate brachytherapy using Monte Carlo simulations. Dosimetric measurements performed on a physical anthropomorphic tissue-equivalent prostate phantom and thermoluminescent dosimeters (TLDs) were used to validate the MC model. Finally the MC model was also used to simulate prostate swelling in a real treatment planning procedure. The obtained results indicate that the parameters mentioned above represent a source of uncertainty in dose assessment in prostate brachytherapy, and can be detrimental to a correct dose evaluation in treatment plannings, and that these parameters can be accurately determined by means of MC simulations with a voxel phantom.
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Affiliation(s)
- P Teles
- CTN Pólo de Loures, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela, LRS, Portugal
| | - S Barros
- CTN Pólo de Loures, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela, LRS, Portugal
| | - S Cardoso
- Universidade Federal do Rio de Janeiro, Av. Pedro Calmon, 550, Rio de Janeiro 21941-901, Brazil
| | - A Facure
- Comissão Nacional de Energia Nuclear, Rua Gal Severiano, 90, Rio de Janeiro 22290-901, Brazil
| | - L A R da Rosa
- Instituto de Radioproteção e Dosimetria, Av. Salvador Allende, Rio de Janeiro 22780-160, Brazil
| | - M Santos
- Instituto de Radioproteção e Dosimetria, Av. Salvador Allende, Rio de Janeiro 22780-160, Brazil
| | - P Pereira
- Dosimetrika, Avenida Olegário Maciel, 231 - Barra da Tijuca, Rio de Janeiro, 22621-200, Brazil
| | - P Vaz
- CTN Pólo de Loures, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela, LRS, Portugal
| | - M Zankl
- Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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Mosleh-Shirazi MA, Hadad K, Faghihi R, Baradaran-Ghahfarokhi M, Naghshnezhad Z, Meigooni AS. EchoSeed Model 6733 Iodine-125 brachytherapy source: improved dosimetric characterization using the MCNP5 Monte Carlo code. Med Phys 2012; 39:4653-9. [PMID: 22894389 DOI: 10.1118/1.4736418] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
This study primarily aimed to obtain the dosimetric characteristics of the Model 6733 (125)I seed (EchoSeed) with improved precision and accuracy using a more up-to-date Monte-Carlo code and data (MCNP5) compared to previously published results, including an uncertainty analysis. Its secondary aim was to compare the results obtained using the MCNP5, MCNP4c2, and PTRAN codes for simulation of this low-energy photon-emitting source. The EchoSeed geometry and chemical compositions together with a published (125)I spectrum were used to perform dosimetric characterization of this source as per the updated AAPM TG-43 protocol. These simulations were performed in liquid water material in order to obtain the clinically applicable dosimetric parameters for this source model. Dose rate constants in liquid water, derived from MCNP4c2 and MCNP5 simulations, were found to be 0.993 cGyh(-1) U(-1) (±1.73%) and 0.965 cGyh(-1) U(-1) (±1.68%), respectively. Overall, the MCNP5 derived radial dose and 2D anisotropy functions results were generally closer to the measured data (within ±4%) than MCNP4c and the published data for PTRAN code (Version 7.43), while the opposite was seen for dose rate constant. The generally improved MCNP5 Monte Carlo simulation may be attributed to a more recent and accurate cross-section library. However, some of the data points in the results obtained from the above-mentioned Monte Carlo codes showed no statistically significant differences. Derived dosimetric characteristics in liquid water are provided for clinical applications of this source model.
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Affiliation(s)
- M A Mosleh-Shirazi
- Center for Research in Medical Physics and Biomedical Engineering and Physics Unit, Radiotherapy Department, Shiraz University of Medical Sciences, Shiraz 71936-13311, Iran.
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An analysis of intraoperative versus post-operative dosimetry with CT, CT–MRI fusion and XMR for the evaluation of permanent prostate brachytherapy implants. Radiother Oncol 2010; 96:166-71. [PMID: 20615565 DOI: 10.1016/j.radonc.2010.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Revised: 05/17/2010] [Accepted: 06/07/2010] [Indexed: 11/23/2022]
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Sahoo S, Palani Selvam T. An EGSnrc investigation of the air-kerma strength, dose rate constant, and radial dose function of 125I brachytherapy sources. Radiol Phys Technol 2009; 2:198-204. [DOI: 10.1007/s12194-009-0066-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Revised: 06/11/2009] [Accepted: 06/11/2009] [Indexed: 11/30/2022]
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Meigooni AS, Luerman CM, Sowards KT. Evaluation of the dose distribution for prostate implants using various 125I and 103Pd sources. Med Phys 2009; 36:1452-8. [PMID: 19472652 DOI: 10.1118/1.3095776] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Recently, several different models of 125I and 103Pd brachytherapy sources have been introduced in order to meet the increasing demand for prostate seed implants. These sources have different internal structures; hence, their TG-43 dosimetric parameters are not the same. In this study, the effects of the dosimetric differences among the sources on their clinical applications were evaluated. The quantitative and qualitative evaluations were performed by comparisons of dose distributions and dose volume histograms of prostate implants calculated for various designs of 125I and 103Pd sources. These comparisons were made for an identical implant scheme with the same number of seeds for each source. The results were compared with the Amersham model 6711 seed for 125I and the Theragenics model 200 seed for 103Pd using the same implant scheme.
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Affiliation(s)
- Ali S Meigooni
- Department of Radiation Medicine, North Shore University Hospital, Manhasset, New York 11030, USA.
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Taylor REP, Rogers DWO. An EGSnrc Monte Carlo-calculated database of TG-43 parameters. Med Phys 2008; 35:4228-41. [DOI: 10.1118/1.2965360] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Acher P, Rhode K, Morris S, Gaya A, Miquel M, Popert R, Tham I, Nichol J, McLeish K, Deehan C, Dasgupta P, Beaney R, Keevil SF. Comparison of Combined X-Ray Radiography and Magnetic Resonance (XMR) Imaging–Versus Computed Tomography–Based Dosimetry for the Evaluation of Permanent Prostate Brachytherapy Implants. Int J Radiat Oncol Biol Phys 2008; 71:1518-25. [PMID: 18513881 DOI: 10.1016/j.ijrobp.2008.03.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2007] [Revised: 01/26/2008] [Accepted: 03/18/2008] [Indexed: 10/22/2022]
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Rivard MJ, Butler WM, DeWerd LA, Huq MS, Ibbott GS, Meigooni AS, Melhus CS, Mitch MG, Nath R, Williamson JF. Supplement to the 2004 update of the AAPM Task Group No. 43 Report. Med Phys 2007; 34:2187-205. [PMID: 17654921 DOI: 10.1118/1.2736790] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Since publication of the 2004 update to the American Association of Physicists in Medicine (AAPM) Task Group No. 43 Report (TG-43U1), several new low-energy photon-emitting brachytherapy sources have become available. Many of these sources have satisfied the AAPM prerequisites for routine clinical use as of January 10, 2005, and are posted on the Joint AAPM/RPC Brachytherapy Seed Registry. Consequently, the AAPM has prepared this supplement to the 2004 AAPM TG-43 update. This paper presents the AAPM-approved consensus datasets for these sources, and includes the following 125I sources: Amersham model 6733, Draximage model LS-1, Implant Sciences model 3500, IBt model 1251L, IsoAid model IAI-125A, Mentor model SL-125/ SH-125, and SourceTech Medical model STM1251. The Best Medical model 2335 103Pd source is also included. While the methodology used to determine these data sets is identical to that published in the AAPM TG-43U1 report, additional information and discussion are presented here on some questions that arose since the publication of the TG-43U1 report. Specifically, details of interpolation and extrapolation methods are described further, new methodologies are recommended, and example calculations are provided. Despite these changes, additions, and clarifications, the overall methodology, the procedures for developing consensus data sets, and the dose calculation formalism largely remain the same as in the TG-43U1 report. Thus, the AAPM recommends that the consensus data sets and resultant source-specific dose-rate distributions included in this supplement be adopted by all end users for clinical treatment planning of low-energy photon-emitting brachytherapy sources. Adoption of these recommendations may result in changes to patient dose calculations, and these changes should be carefully evaluated and reviewed with the radiation oncologist prior to implementation of the current protocol.
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Affiliation(s)
- Mark J Rivard
- Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
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Meigooni AS, Dini SA, Awan SB, Dou K, Koona RA. Theoretical and experimental determination of dosimetric characteristics for ADVANTAGE™ Pd-103 brachytherapy source. Appl Radiat Isot 2006; 64:881-7. [PMID: 16713277 DOI: 10.1016/j.apradiso.2006.03.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 02/27/2006] [Accepted: 03/27/2006] [Indexed: 11/22/2022]
Abstract
ADVANTAGE Pd-103 brachytherapy source has been recently introduced by IsoAid for prostate permanent implants. Dosimetric characteristics (Dose rate constant, radial dose function, 2D-, and 1D-anisotropy functions) of this source model have been determined using both theoretical and experimental methods, following the updated TG-43U1 protocol. Derivation of the dose rate constant was based on recent NIST WAFAC calibration performed in accordance with the 1999 Standards. Measurements were performed in Solid Water using LiF TLD chips and the theoretical calculations were performed in Solid Water and liquid water phantom materials using PTRAN Monte Carlo code. The results of the Monte Carlo simulation have shown a dose rate constant of 0.69 cGyh(-1) U(-1) in liquid water and 0.67 cGyh(-1) U(-1) in Solid Water medium. The measured dose rate constant in Solid Water was found to be 0.68+/-8% cGyh(-1) U(-1), which is in a good agreement (within +/-5%) to the Monte Carlo simulated data. The 2D- and 1D-anisotropy functions of the ADVANTAGE Pd-103 source were calculated for radial distances ranging from 0.5 to 5.0 cm. Radial dose function was determined for radial distances ranging from 0.2 to 8.0 cm using line source approximation. All these calculations are based on L(eff) equal to 3.61 cm, calculated following TG-43U1 recommendations. The tabulated data for 2D-anisotropy function, 1D-anisotropy function, dose rate constant and radial dose function have been produced for clinical application of this source model.
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Affiliation(s)
- Ali S Meigooni
- Department of Radiation Medicine, University of Kentucky Medical Center, 800 Rose Street, Lexington, Kentucky 40536, USA.
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Nath R, Yue N. Dosimetric characterization of an encapsulated interstitial brachytherapy source of 125I on a tungsten substrate. Brachytherapy 2002; 1:102-9. [PMID: 15062178 DOI: 10.1016/s1538-4721(02)00010-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2001] [Revised: 02/26/2002] [Accepted: 03/07/2002] [Indexed: 10/27/2022]
Abstract
PURPOSE Recently, a new design of an encapsulated 125I source using a tungsten substrate has been introduced by Best Medical International and named as Best Model 2301 source. In contrast to model 6711 source that uses silver as substrate, the model 2301 source does not yield fluorescent x rays (22.1 keV and 25.5 keV) in the energy range of dosimetric interest. This changes the dosimetric characteristics of the source and experimental determination of these characteristics is needed. METHODS AND MATERIALS In this work, the dosimetric characteristics of the tungstenbased 125I source were measured using LiF TLDs in a Solid Water phantom. The dose rate constant as well as the radial dose function and anisotropy function were measured. RESULTS The dose rate constant for the tungsten-based source was determined to be 1.02 +/- 0.07 cGy h(-1) U(-1) in contrast to the previously reported value of 0.98 for the silver-based model 6711 source. The radial dose function for the tungsten-based model 2301 source decreases slightly less rapidly with distance than that for the silver-based model 6711 source. Considerable differences in the anisotropy functions between the two sources were observed. CONCLUSIONS Dosimetric parameters of the Model 2301 source, based on AAPM TG-43 formalism, have been experimentally determined.
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Affiliation(s)
- Ravinder Nath
- Department of Therapeutic Radiology, Yale University School of Medicine, PO Box 208040, New Haven, CT 06520-8040, USA.
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