Khalid Alhamad , Hasham Ahmed , Dean Cutajar , Joel Poder , Anatoly Rosenfeld , Enbang Li
{"title":"用光纤剂量计模拟和测量HDR近距离放射治疗源剂量参数","authors":"Khalid Alhamad , Hasham Ahmed , Dean Cutajar , Joel Poder , Anatoly Rosenfeld , Enbang Li","doi":"10.1016/j.radmeas.2025.107469","DOIUrl":null,"url":null,"abstract":"<div><div>The aim of this study is to evaluate the feasibility of using CsI(Tl)-based fiber-optic dosimetry system for TG-43 dosimetric characterization of the Flexisource <sup>192</sup>Ir HDR brachytherapy source. The investigation focuses on anisotropy and radial dose function measurements and assesses the impact of fluorescence and Cherenkov radiation on signal accuracy, with validation through TOPAS Monte Carlo simulations.</div><div>Thallium Doped-Cesium Iodide (CsI(Tl)) scintillation crystals were used within a custom-designed PMMA phantom. The experiment, conducted with a Flexitron afterloader and <sup>192</sup>Ir Flexisource, involved measurements at distances of 1.5–6 cm and polar angles of 20°–155°, with increments matching those in the published studies.</div><div>Comprehensive dosimetric data were collected, revealing the influence of fluorescence and Cherenkov radiation on anisotropy function measurements. The radial dose function showed good agreement with simulation, with minor deviations attributed to limitations in the treatment planning. TOPAS Monte Carlo simulations demonstrated consistent agreement with experimental results, yielding a maximum absolute difference of 0.035 in the experimental data and a maximum deviation of 2.6% in anisotropy function validation against published reference data, further confirming the reliability of both the experimental approach and the simulation model.</div><div>These findings underscore the importance of accounting for fluorescence and Cherenkov radiation in detector signal response. Unlike earlier approaches that primarily focused on signal removal or hardware suppression techniques, this study demonstrates the integration of these contributions directly into calibration models to improve dosimetric precision. By refining these calibration methods, fiber-optic detectors may be further developed into simple, accurate, and clinically viable tools for brachytherapy applications.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107469"},"PeriodicalIF":2.2000,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Simulation and measurements of HDR brachytherapy source dosimetric parameters using a fiber-optic dosimeter\",\"authors\":\"Khalid Alhamad , Hasham Ahmed , Dean Cutajar , Joel Poder , Anatoly Rosenfeld , Enbang Li\",\"doi\":\"10.1016/j.radmeas.2025.107469\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The aim of this study is to evaluate the feasibility of using CsI(Tl)-based fiber-optic dosimetry system for TG-43 dosimetric characterization of the Flexisource <sup>192</sup>Ir HDR brachytherapy source. The investigation focuses on anisotropy and radial dose function measurements and assesses the impact of fluorescence and Cherenkov radiation on signal accuracy, with validation through TOPAS Monte Carlo simulations.</div><div>Thallium Doped-Cesium Iodide (CsI(Tl)) scintillation crystals were used within a custom-designed PMMA phantom. The experiment, conducted with a Flexitron afterloader and <sup>192</sup>Ir Flexisource, involved measurements at distances of 1.5–6 cm and polar angles of 20°–155°, with increments matching those in the published studies.</div><div>Comprehensive dosimetric data were collected, revealing the influence of fluorescence and Cherenkov radiation on anisotropy function measurements. The radial dose function showed good agreement with simulation, with minor deviations attributed to limitations in the treatment planning. TOPAS Monte Carlo simulations demonstrated consistent agreement with experimental results, yielding a maximum absolute difference of 0.035 in the experimental data and a maximum deviation of 2.6% in anisotropy function validation against published reference data, further confirming the reliability of both the experimental approach and the simulation model.</div><div>These findings underscore the importance of accounting for fluorescence and Cherenkov radiation in detector signal response. Unlike earlier approaches that primarily focused on signal removal or hardware suppression techniques, this study demonstrates the integration of these contributions directly into calibration models to improve dosimetric precision. By refining these calibration methods, fiber-optic detectors may be further developed into simple, accurate, and clinically viable tools for brachytherapy applications.</div></div>\",\"PeriodicalId\":21055,\"journal\":{\"name\":\"Radiation Measurements\",\"volume\":\"187 \",\"pages\":\"Article 107469\"},\"PeriodicalIF\":2.2000,\"publicationDate\":\"2025-06-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Radiation Measurements\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1350448725000988\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"NUCLEAR SCIENCE & TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Radiation Measurements","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1350448725000988","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
Simulation and measurements of HDR brachytherapy source dosimetric parameters using a fiber-optic dosimeter
The aim of this study is to evaluate the feasibility of using CsI(Tl)-based fiber-optic dosimetry system for TG-43 dosimetric characterization of the Flexisource 192Ir HDR brachytherapy source. The investigation focuses on anisotropy and radial dose function measurements and assesses the impact of fluorescence and Cherenkov radiation on signal accuracy, with validation through TOPAS Monte Carlo simulations.
Thallium Doped-Cesium Iodide (CsI(Tl)) scintillation crystals were used within a custom-designed PMMA phantom. The experiment, conducted with a Flexitron afterloader and 192Ir Flexisource, involved measurements at distances of 1.5–6 cm and polar angles of 20°–155°, with increments matching those in the published studies.
Comprehensive dosimetric data were collected, revealing the influence of fluorescence and Cherenkov radiation on anisotropy function measurements. The radial dose function showed good agreement with simulation, with minor deviations attributed to limitations in the treatment planning. TOPAS Monte Carlo simulations demonstrated consistent agreement with experimental results, yielding a maximum absolute difference of 0.035 in the experimental data and a maximum deviation of 2.6% in anisotropy function validation against published reference data, further confirming the reliability of both the experimental approach and the simulation model.
These findings underscore the importance of accounting for fluorescence and Cherenkov radiation in detector signal response. Unlike earlier approaches that primarily focused on signal removal or hardware suppression techniques, this study demonstrates the integration of these contributions directly into calibration models to improve dosimetric precision. By refining these calibration methods, fiber-optic detectors may be further developed into simple, accurate, and clinically viable tools for brachytherapy applications.
期刊介绍:
The journal seeks to publish papers that present advances in the following areas: spontaneous and stimulated luminescence (including scintillating materials, thermoluminescence, and optically stimulated luminescence); electron spin resonance of natural and synthetic materials; the physics, design and performance of radiation measurements (including computational modelling such as electronic transport simulations); the novel basic aspects of radiation measurement in medical physics. Studies of energy-transfer phenomena, track physics and microdosimetry are also of interest to the journal.
Applications relevant to the journal, particularly where they present novel detection techniques, novel analytical approaches or novel materials, include: personal dosimetry (including dosimetric quantities, active/electronic and passive monitoring techniques for photon, neutron and charged-particle exposures); environmental dosimetry (including methodological advances and predictive models related to radon, but generally excluding local survey results of radon where the main aim is to establish the radiation risk to populations); cosmic and high-energy radiation measurements (including dosimetry, space radiation effects, and single event upsets); dosimetry-based archaeological and Quaternary dating; dosimetry-based approaches to thermochronometry; accident and retrospective dosimetry (including activation detectors), and dosimetry and measurements related to medical applications.