Academic Journal

Monte Carlo intercomparison of TG-43 dosimetric parameters for clinical192Ir and125I brachytherapy sources.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος: Monte Carlo intercomparison of TG-43 dosimetric parameters for clinical192Ir and125I brachytherapy sources.
Συγγραφείς: Araújo LF; Department of Nuclear Engineering, School of Engineering, Federal University of Minas Gerais-UFMG, Belo Horizonte, Brazil., Amin A; Department of Nuclear Engineering, School of Engineering, Federal University of Minas Gerais-UFMG, Belo Horizonte, Brazil.; School of Pharmacy, Federal University of Minas Gerais-UFMG, Belo Horizonte, Brazil., Sabino AP; School of Pharmacy, Federal University of Minas Gerais-UFMG, Belo Horizonte, Brazil., Fonseca TCF; Department of Nuclear Engineering, School of Engineering, Federal University of Minas Gerais-UFMG, Belo Horizonte, Brazil.; Nuclear Technology Development Center-CDTN, Belo Horizonte, Brazil.
Πηγή: Physics in medicine and biology [Phys Med Biol] 2026 Sep 28; Vol. 71 (19). Date of Electronic Publication: 2026 Sep 28.
Τύπος έκδοσης: Journal Article; Comparative Study
Γλώσσα: English
Στοιχεία περιοδικού: Publisher: IOP Publishing Country of Publication: England NLM ID: 0401220 Publication Model: Electronic Cited Medium: Internet ISSN: 1361-6560 (Electronic) Linking ISSN: 00319155 NLM ISO Abbreviation: Phys Med Biol Subsets: MEDLINE
Imprint Name(s): Original Publication: Bristol : IOP Publishing
Ιατρικοί όροι (MeSH): Brachytherapy*/instrumentation , Iridium Radioisotopes*/therapeutic use , Iodine Radioisotopes*/therapeutic use , Monte Carlo Method*, Radiometry ; Radiotherapy Dosage ; Phantoms, Imaging
Περίληψη: Objective.This study presents a rigorous, simultaneous Monte Carlo (MC) intercomparison of three general-purpose computational codes, MCNP6.2, TOPAS 3.9, and PHITS 3.341, for the calculation and validation of TG-43 dosimetric parameters for the clinical microSelectron-HDR v2Ir and Theragenics-AgX100I brachytherapy sources under realistic, unsimplified photon emission spectra.Approach.Simulations were performed in a spherical liquid water phantom with a radius of 18.5 cm to ensure full-scatter conditions. Dose was scored in small, distance-dependent spherical water scoring cells with varying radii. Discrete, unsimplified photon emission spectra from ICRP Publication 107 were implemented in all three codes. To address gaps in the literature, a computationally efficient simplified geometry previously adopted for theIr source was evaluated, while theI source was modeled with high geometric fidelity. The radial dose and anisotropy functions were calculated, the radial dose data were fitted using fifth-degree polynomials, and the resulting datasets were benchmarked against established TG-43 consensus reference data.Main results.The three MC codes demonstrated good overall agreement. For theIr source, the simplified geometry reproduced the consensus reference data within thecriterion over the clinically relevant radial range, demonstrating its dosimetric suitability within the TG-43 framework. For the low-energyI source, larger deviations, reaching approximately, were observed at short radial distances (cm), consistent with the greater sensitivity of low-energy photon transport to attenuation and shielding effects associated with the source encapsulation and internal components. At distances beyond approximatelycm, the results showed substantially improved agreement, with deviations generally remaining within. Fifth-degree polynomial fitting accurately reproduced the radial dose function, with deviations predominantly remaining below the recommendedcriterion within the clinically relevant radial intervals.Significance.This work establishes a robust, cross-validated computational baseline for brachytherapy dosimetry using general-purpose MC codes under realistic photon emission spectra. The validation of the simplifiedIr geometry supports its use in computationally efficient simulations, while the characterization of the low-energyI source provides relevant information for high-precision dosimetry and future investigations of low-energy radiation interactions in radiosensitization studies.
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Contributed Indexing: Keywords: MCNP; Monte Carlo Simulation; PHITS; TG-43; TOPAS; brachytherapy
Substance Nomenclature: 0 (Iridium Radioisotopes)
0 (Iodine Radioisotopes)
GVO776611R (Iodine-125)
0 (Iridium-192)
Entry Date(s): Date Created: 20260915 Date Completed: 20260928 Latest Revision: 20260928
Update Code: 20260928
DOI: 10.1088/1361-6560/aea7f6
PMID: 42743978
Βάση Δεδομένων: MEDLINE