Radiation Medicine and Protection最新文献

{"title":"Occupational radiation exposure analysis in industrial radiography in Bangladesh","authors":"Mehedi Hassan,&nbsp;Shahadat Hossain,&nbsp;M.M. Mahfuz Siraz,&nbsp;Shikha Pervin,&nbsp;Nazneen Sultana,&nbsp;Md Zakir Hossain,&nbsp;Selina Yeasmin","doi":"10.1016/j.radmp.2025.03.002","DOIUrl":"10.1016/j.radmp.2025.03.002","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate the workload management and guarantee the technical concerns for an appropriate radiation protection method in non-destructive testing (NDT) industries in Bangladesh.</div></div><div><h3>Methods</h3><div>The radiation exposure for 721 workers was investigated in industrial radiography through Bangladesh during 2019–2022. A thermoluminescence dosimeter (TLD-100) was used to measure the occupational exposure with the operational dose quantity <em>H</em>_p(10). All the readout procedures were completed using the Harshaw TLD reader (model 4500).</div></div><div><h3>Results</h3><div>The collective effective dose was 75.73, 115.35, 150.18, and 96 ​mSv in year 2019, 2020, 2021, and 2022, respectively. The maximum effective dose received among the workers was 19.45, 3.8, 19.19, and 19.53 ​mSv, respectively, which remained within the stipulated dose limits imposed by Nuclear Safety and Radiation Control (NSRC) Rules-1997, Bangladesh and International Commission on Radiological Protection (ICRP-103). The mean annual individual dose was 0.53, 0.8, 0.83, and 0.39 ​mSv in 2019, 2020, 2021, and 2022, respectively. The mean value of excess life-time cancer risk (ELCR) was found 1.12 ​× ​10⁻³.</div></div><div><h3>Conclusion</h3><div>The industrial radiography facilities of Bangladesh may be certain that their current safety protocols are adequate. Additionally, few recommendations for safe industrial radiography practices have also been offered.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 2","pages":"Pages 107-111"},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Survival benefits and toxicity effects of radiotherapy and immunotherapy treatments in melanoma patients with brain metastases: A meta-analysis","authors":"Jialing Wen ,&nbsp;Xiangdi Meng ,&nbsp;Wenchao Gu ,&nbsp;Shenke Zhang ,&nbsp;Li Sui ,&nbsp;Gang Guo ,&nbsp;Liang Yan ,&nbsp;Wangcai Ren ,&nbsp;Xuanzhang Tu ,&nbsp;Kensuke Osada ,&nbsp;Takashi Shimokawa ,&nbsp;Yang Li ,&nbsp;Liqiu Ma","doi":"10.1016/j.radmp.2025.02.001","DOIUrl":"10.1016/j.radmp.2025.02.001","url":null,"abstract":"<div><h3>Objective</h3><div>To compare the efficacy and toxicity of four treatment strategies in patients with MBMs.</div></div><div><h3>Methods</h3><div>A systematic literature search of the Cochrane, PubMed, Embase, Web of Science, and OVID Medline databases was performed until July 24, 2024. A total of four therapeutic modalities for MBMs, including immune checkpoint inhibitor (ICI) monotherapy, radiotherapy (RT) alone, ICI combined with RT (ICI ​+ ​RT), and dual ICI therapy (ICI ​+ ​ICI), were evaluated by the overall survival (OS), intracranial progression-free survival (iPFS), and adverse effect (AE). The meta-analysis was performed using R language and registered in PROSPERO (registration no. CRD42023480912).</div></div><div><h3>Results</h3><div>This study included 33 studies comprising 2,496 patients with MBMs. ICI combined with RT and dual ICI therapy improved the 6 and 12-month OS rates compared with ICI monotherapy and RT alone. There was no significant difference in OS between the ICI + RT group and the ICI + ICI group. Similar results were observed for iPFS, with the combination treatment groups showing a significant difference compared with the treatment groups alone. However, no significant difference was observed in 1-year iPFS between the ICI + RT group and the ICI + ICI group (<em>P</em> ​= ​0.07), whereas the ICI + ICI group demonstrated superior 2-year iPFS compared with the ICI + RT group (<em>P</em> ​&lt; 0.05). Furthermore, the survival advantages of combination therapy gradually decreased with increasing duration of treatment. Additionally, compared with ICI monotherapy, dual ICI therapy significantly increased the incidence of AEs over grade 3 (ICI ​+ ​ICI: 57% <em>vs.</em> ICI: 11%, <em>P</em> ​&lt; ​0.0001), whereas ICI combined with RT did not significantly differ (ICI ​+ ​RT: 19% <em>vs.</em> ICI: 11%, <em>P</em> ​= ​0.14).</div></div><div><h3>Conclusion</h3><div>The combination of ICI with RT offers superior survival benefits without increasing toxicity in patients with MBMs. However, this survival benefit decreases over time, and further optimizing the treatment strategy is essential for improving the outcomes of patients with MBMs.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 2","pages":"Pages 91-102"},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Swift prediction of personalized head and chest organ doses from CT examinations via neural networks with optimized quantity of hidden layers and radiomics features","authors":"Wencheng Shao ,&nbsp;Xin Lin ,&nbsp;Ying Huang ,&nbsp;Liangyong Qu ,&nbsp;Weihai Zhuo ,&nbsp;Haikuan Liu","doi":"10.1016/j.radmp.2025.02.002","DOIUrl":"10.1016/j.radmp.2025.02.002","url":null,"abstract":"<div><h3>Objective</h3><div>To utilize radiomics features to enhance the prediction of personalized organ doses from CT scans, in order to explore methods for improving neural network-based models.</div></div><div><h3>Methods</h3><div>Patient CT DICOM files were processed using DeepViewer to define regions of interest (ROIs) in their organs. Radiomics features were extracted from the CT images and ROIs, and benchmark organ doses were calculated using Monte Carlo simulations. Fully-connected neural networks (FCNN) were trained with radiomics features to predict organ doses. The FCNN model was optimized by adjusting the number of input radiomics features and FCNN layers. Performance was evaluated using relative root mean squared error (<em>RRMSE</em>) and <em>R</em>-squared (<em>R</em>²).</div></div><div><h3>Results</h3><div>Higher RRMSE and lower <em>R</em>² values are observed when fewer than 30 input radiomics features are used for head CTs and fewer than 10 for chesst CTs. Increasing input features didn't significantly improve FCNN's performance. For head CTs, FCNN's layer quantities affected predictive stability, with better robustness observed with 4- and 5-layer FCNN. Specifically, the median RRMSE was reduced to 8.14% for the brain, 10.27% for the left eye, and 10.16% for the right eye when using 30 or more radiomics features. For chest CTs, the model's predictive stability was less sensitive to the number of layers, with median RRMSE values of 9.58% for the left lung and 9.44% for the right lung, and <em>R</em>² values of 0.76 for both lungs.</div></div><div><h3>Conclusions</h3><div>Optimizing feature quantities and neural network layers enhances performance in predicting organ doses from CT scans. Specifically, head CTs show optimal results with 4–5 layers, while chest CTs do not significantly benefit from increased layers.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 2","pages":"Pages 81-90"},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence for chest X-ray image enhancement","authors":"Liming Song ,&nbsp;Hongfei Sun ,&nbsp;Haonan Xiao ,&nbsp;Sai Kit Lam ,&nbsp;Yuefu Zhan ,&nbsp;Ge Ren ,&nbsp;Jing Cai","doi":"10.1016/j.radmp.2024.12.003","DOIUrl":"10.1016/j.radmp.2024.12.003","url":null,"abstract":"<div><div>The chest X-ray (CXR) imaging has been the most frequently performed radiographic examination for decades, and its demand continues to grow due to their critical role in diagnosing various diseases. However, the image quality of CXR has long been a factor limiting their diagnostic accuracy. As a post-processing procedure, image enhancement can cost-effectively improve image quality. Recently, the successful application of deep learning (DL) algorithms in medical image analysis has prompted researchers to propose and design DL-based CXR image enhancement algorithms. This review examines advancements in CXR image enhancement methods from 2018 to 2023, categorizing them into four groups: bone suppression, image denoising, super-resolution reconstruction, and contrast enhancement. For each group, the unique approaches, strengths, and challenges are analyzed. The review concludes by discussing shared challenges across these methods and proposing directions for future research.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 61-68"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increased dicentric chromosome in peripheral lymphocytes is related to acute skin toxicity induced by radiotherapy in cancer patients","authors":"Minjie Li ,&nbsp;Yu Gao ,&nbsp;Lin Han ,&nbsp;Ping Wang ,&nbsp;Jie Li ,&nbsp;Junhua Song ,&nbsp;Shasha Du ,&nbsp;Yunfei Zhang ,&nbsp;Yumin Lyu","doi":"10.1016/j.radmp.2024.07.003","DOIUrl":"10.1016/j.radmp.2024.07.003","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the impacts of radiotherapy (RT) on dicentric chromosomes in peripheral blood lymphocytes of cancer patients, in order to explore the relationship between dicentric chromosomes and RT-induced adverse reactions.</div></div><div><h3>Methods</h3><div>A total of 33 cancer patients after postoperative RT in a tertiary hospital from October 2021 to May 2022 were enrolled in this study. These patients were grouped according to the grade of acute skin and marrow toxicities determined based on the scoring criteria for acute morbidity developed by the Radiation Therapy Oncology Group (RTOG). Peripheral blood samples were collected from each patient before and after RT, followed by whole-blood lymphocyte culture and chromosome analysis. Dicentric chromosomes were searched automatically using a high-throughput chromosome analysis system and were then confirmed manually. Finally, the relationships of the frequency of dicentric chromosomes (also referred to as the dic frequency) with acute skin and marrow toxicities were assessed.</div></div><div><h3>Results</h3><div>After RT, the mean counts of white blood cells (WBCs), lymphocytes, and platelets significantly decreased, while the red blood cells (RBCs) and hemoglobin notably increased (<em>P</em> ​&lt; ​0.001), while the dic frequency was elevated remarkably, significantly higher in patients with higher-grade (&gt;1) acute skin toxicities compared to those with lower-grade (=1) acute skin toxicities (<em>Z</em> ​= ​−1.985, <em>P</em> ​= ​0.047). However, no significant relationship was observed between the dic frequency and acute marrow toxicity after RT (<em>P</em> ​&gt; ​0.05). Logistic regression showed that radiosensitivity denoted by the post-RT dic frequency in peripheral blood lymphocytes produced insignificant impacts on the severity of RT-induced acute skin toxicities (<em>P</em> ​= ​0.060).</div></div><div><h3>Conclusion</h3><div>The elevated dic frequency in peripheral blood lymphocytes of cancer patients with higher-grade acute skin toxicities suggests enhanced radiosensitivity of peripheral blood lymphocytes, which is associated with the occurrence of RT-induced adverse reactions.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 22-27"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the detection efficiencies of liquid 99Tcm, 131I, and 18F in a well-type NaI(Tl) gamma spectrometer","authors":"Jiayu Liu,&nbsp;Xiaojun Lu,&nbsp;Chao Zhao","doi":"10.1016/j.radmp.2024.12.001","DOIUrl":"10.1016/j.radmp.2024.12.001","url":null,"abstract":"<div><h3>Objective</h3><div>To assess the detection efficiencies of liquid radioisotopes in a well-type NaI(Tl) gamma spectrometer, focusing on the short-lived isotopes ⁹⁹Tc^m, ¹³¹I, and ¹⁸F.</div></div><div><h3>Methods</h3><div>The detection efficiencies of liquid ⁹⁹Tc^m, ¹³¹I, and ¹⁸F in a well-type NaI(Tl) gamma spectrometer were systematically investigated through calibration experiments and Monte Carlo simulations, and accounting for the coincidence-summing effect.</div></div><div><h3>Results</h3><div>The results indicated that the detection efficiencies of ⁹⁹Tc^m, ¹³¹I, and ¹⁸F varied from 64.4% to 72.3%, 34.8%–43.1% and 27.3%–28.5% for different sample volumes ranging from 15 ​mL to 80 ​mL, respectively. The simulated detection efficiencies were highly consistent with the experimental results, with a largest relative deviation of 5% for the 3 radionuclides and 4 different sample volumes.</div></div><div><h3>Conclusion</h3><div>The consistent results between the calibration experiments and Monte Carlo simulations reveal that this measuring device possesses high detection efficiencies of ⁹⁹Tc^m, ¹³¹I, and ¹⁸F, making it suitable for measuring low-level activity radioactive liquids, such as radioactive waste liquids to be discharged.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 46-50"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological effectiveness of combined exposure to neutrons and gamma radiation applied in two orders of sequence: Relevance for biological dosimetry after nuclear emergencies","authors":"Tomas Palmqvist ,&nbsp;Milagrosa Lopez-Riego ,&nbsp;Martin Bucher ,&nbsp;Ursula Oestreicher ,&nbsp;Stefan Pojtinger ,&nbsp;Ulrich Giesen ,&nbsp;Iuliana Toma-Dasu ,&nbsp;Andrzej Wojcik","doi":"10.1016/j.radmp.2024.10.004","DOIUrl":"10.1016/j.radmp.2024.10.004","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the potential impact of two different combinations of neutron and gamma radiation on gene expression and dicentric chromosomes in peripheral blood mononuclear cells (PBMC).</div></div><div><h3>Methods</h3><div>Whole blood from 3 human donors was exposed to neutrons with an energy spectrum similar to that of the Hiroshima uranium bomb, to gamma radiation from a ⁶⁰Co source and to a 50:50 combination of both radiations, given in two orders of sequence. In all cases the total doses were 0.5, 0.75 and 1.0 ​Gy. Dicentric chromosomes were analyzed by light microscopy and the expression of six known radiation-responsive genes BBC3, CDKN1A, FDXR, GADD45A, MDM2, and XPC were analyzed by RT-qPCR.</div></div><div><h3>Results</h3><div>Per unit dose, exposure to neutrons lead to a higher level of dicentrics and gene expression as compared to gamma radiation. Dose-response relationships for both endpoints were linear, allowing calculating the expected outcome of combined exposure by arithmetic. For dicentric chromosomes, the RBE values for ⁶⁰Co → neutrons, neutrons → ⁶⁰Co and neutrons were 4.05, 3.62 and 7.30, respectively. For gene expression the RBE values were gene-specific, but showed values in the range of 1.14–3.01 for ⁶⁰Co → neutrons, 1.33–2.68 for neutrons → ⁶⁰Co and 1.39–3.91 for neutrons.</div></div><div><h3>Conclusions</h3><div>The results demonstrate that combined exposure to neutrons and gamma radiation, regardless of the order of sequence, leads to an additive response at both endpoints. This indicates that calibration curves for mixed beams can be constructed from dose response relationships of the single beam components.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 1-10"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ginsenoside Rg1 alleviates chronic testicular damage caused by cranial irradiation through the SCF/PI3K/Akt/mTOR pathway in mice","authors":"Qiuhua Zhou ,&nbsp;Yiquan Ou ,&nbsp;Xiangsheng Tian ,&nbsp;Yujun Ning ,&nbsp;Yuwei Mao ,&nbsp;Weichao Zhao ,&nbsp;Dingxin Long","doi":"10.1016/j.radmp.2024.12.002","DOIUrl":"10.1016/j.radmp.2024.12.002","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate whether Ginsenoside Rg1 can mitigate the adverse effects of cranial irradiation on distal reproductive function in mice and to explore the underlying mechanisms.</div></div><div><h3>Methods</h3><div>Forty male C57BL/6J mice were randomly divided to four groups [Control, irradiation (IR), IR ​+ ​Rg1, Rg1), IR ​+ ​Rg1 and Rg1 group treated with intraperitoneal injections of Ginsenoside Rg1 for 30 ​d, followed by single-dose irradiation of 5 ​Gy X-ray irradiation (2 ​Gy/min) for the IR and IR ​+ ​Rg1 group. After three months, testicles, whole brain, and serum samples were collected for analysis.</div></div><div><h3>Results</h3><div>Histological staining, transmission electron microscopy, sperm analysis, and immunofluorescence demonstrated that Ginsenoside Rg1 ameliorated structural and functional damage to the testicles, enhanced sperm count (IR: 20.70 ​± ​1.62 <em>vs.</em> IR ​+ ​Rg1: 33.93 ​± ​2.20, <em>t</em> ​= ​−13.23, <em>P</em> ​&lt; ​0.05), and reduced sperm malformation rates (IR: 46.33 ​± ​2.18 <em>vs.</em> IR ​+ ​Rg1: 39.00 ​± ​1.67, <em>t</em> ​= ​7.33, <em>P</em> ​&lt; ​0.05). Further Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and Enzyme linked immunosorbent assay (ELISA) assays demonstrated that Rg1 inhibited testicular apoptosis (IR: 3.21 ​± ​0.28 <em>vs.</em> IR ​+ ​Rg1: 1.81 ​± ​0.18, <em>t</em> ​= ​1.40, <em>P</em> ​&lt; ​0.05) and modulated serum testosterone (IR: 4.47 ​± ​0.23 <em>vs.</em> IR ​+ ​Rg1: 6.65 ​± ​0.09, <em>t</em> ​= ​−2.18, <em>P</em> ​&lt; ​0.05), GnRH (IR: 24.37 ​± ​0.92 <em>vs.</em> IR ​+ ​Rg1: 32.98 ​± ​1.33, <em>t</em> ​= ​−8.61, <em>P</em> ​&lt; ​0.05), and FSH levels (IR: 1.41 ​± ​0.11 <em>vs.</em> IR ​+ ​Rg1: 2.69 ​± ​0.21, <em>t</em> ​= ​−1.28, <em>P</em> ​&lt; ​0.05). Additionally, quantitative PCR and Western blot showed that Rg1 downregulated SCF, p-PI3K, p-Akt, and mTOR protein expressions in irradiated mice.</div></div><div><h3>Conclusions</h3><div>Ginsenoside Rg1 potentially alleviate chronic testicular structural and functional damage by inhibiting germ cell apoptosis through the modulation of the HPG axis and the PI3K/Akt/mTOR pathway, suggesting that it is a potential therapeutic agent for reproductive disorders induced by cranial irradiation.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 11-21"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radioactivity concentration of 14C in the air of 14C urea breath test rooms and the resulting internal dose to medical staff","authors":"Bei Yu ,&nbsp;Fei Chen ,&nbsp;Jing Cao ,&nbsp;Dingxin Long","doi":"10.1016/j.radmp.2024.08.002","DOIUrl":"10.1016/j.radmp.2024.08.002","url":null,"abstract":"<div><h3>Objective</h3><div>To monitor the radioactivity concentration of ¹⁴C in the air of rooms used to perform ¹⁴C urea breath tests, and evaluate the contamination status of ¹⁴C released during such tests, and assess the occupational health risk to medical staff working in such areas.</div></div><div><h3>Methods</h3><div>¹⁴CO₂ in air was absorbed from the air and turned into calcium carbonate through a chemical reaction. Then, calcium carbonate was prepared into a suspension in a low-potassium glass vial. The sample was analyzed using a low-background liquid scintillation counter.</div></div><div><h3>Results</h3><div>The radioactivity concentrations of ¹⁴C in air of the breath-test rooms in hospitals and physical examination institutions range from 1.35 to 18.41 Bq/m³. The annual committed dose for medical staff was estimated to be between 2.01 × 10⁻² and 2.74 × 10⁻¹ μSv.</div></div><div><h3>Conclusions</h3><div>Our results reveal a significant increase of ¹⁴C radioactivity concentration in the air of breath-test rooms, but the resulting committed dose is much lower than the limits prescribed by the International Commission on Radiological Protection (ICRP). However, the potential risk of long-term exposure to low-dose radiation should be paid more attention.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 43-45"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive analysis of peripheral dose in electron beam therapy with a Varian TrueBeam Linac","authors":"Kapil Dev Maharaj ,&nbsp;Mahsheed Sabet ,&nbsp;Joshua Dass ,&nbsp;Mounir Ibrahim ,&nbsp;Talat Mahmood ,&nbsp;Pejman Rowshanfarzad","doi":"10.1016/j.radmp.2024.10.003","DOIUrl":"10.1016/j.radmp.2024.10.003","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the characteristics of peripheral doses outside electron-beam applicators in Varian TrueBeam linacs.</div></div><div><h3>Method</h3><div>Peripheral doses outside the electron applicator were measured for 6-, 9- and 12-MeV beams at the maximum dose depth (<em>D</em>_max) for each energy source and at a source-to-surface distance (SSD) of 100 cm. Measurements were performed using EBT3 films in solid water phantoms. The impact of field size on the penumbra width and peripheral doses was studied using various cutouts, including 3 ​cm ​× ​3 ​cm, 6 ​cm ​× ​6 ​cm, and 10 ​cm ​× ​10 ​cm in a 10 ​cm ​× ​10 ​cm applicator with the gantry and collimator at 0°. The influence of the applicator size was investigated using a circular cutout of 5 ​cm in diameter for various applicator sizes, including 6 ​cm ​× ​6 ​cm, 10 ​cm ​× ​10 ​cm, 15 ​cm ​× ​15 ​cm, 20 cm ​× ​20 ​cm, and 25 ​cm ​× ​25 ​cm, at <em>D</em>_max for each energy, while keeping the gantry and collimator angle at 0°. The measured dose profiles were compared with the Eclipse treatment planning system (TPS) predicted dose profiles. The effect of varying gantry angles (0°, 90°, and 270°) for a 3 ​cm ​× ​3 ​cm cutout in a 10 ​cm ​× ​10 ​cm applicator for each energy source and varying collimator angles (0°, 90°, and 270°) for a 10 ​cm ​× ​10 ​cm field were investigated to determine their effects on the penumbra widths and peripheral doses.</div></div><div><h3>Results</h3><div>Both the penumbra width and peripheral dose values increased with energy across different field sizes, gantry angles, collimator angles, and applicator sizes. Root mean square deviation (RMSD) analysis indicated minimal differences between the measured profiles and TPS data. Peripheral doses remained below 5% of the maximum dose approximately 10–15 ​mm away from the field edges, suggesting the potential for implementing additional shielding where required.</div></div><div><h3>Conclusions</h3><div>This study highlights the importance of considering peripheral doses in electron radiotherapy. It is important to note the impact on healthy tissues beyond the treatment area to ensure patient safety and prevent the long-term side effects of treatment. These findings emphasize the necessity of implementing appropriate measures to minimize peripheral doses.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 28-36"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}