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Background: This study aimed to investigate the occupational exposure of undergraduate radiography students to ionising radiation and evaluate the effectiveness of safety protocols and training in reducing radiation exposure. Methods: This study tracked undergraduate radiography students from the University of Sharjah, UAE, using thermoluminescent dosimeters (TLDs) from 2015 to 2023. TLD readings were conducted every 15 weeks during 384 h of clinical placement. This study encompassed various radiographic procedures, and the TLDs were used to measure shallow (HP (0.07)) and deep doses (HP (10)). Results: A data analysis from 599 dosimeters revealed an average of 74 students annually. The average effective doses for HP (10) and HP (0.07) were 0.227 mSv and 0.222 mSv, respectively. These doses were well-below the recommended annual limits. Conclusion: This study's results indicated that radiography students' occupational radiation exposure during clinical training was within the safe limits, demonstrating the effectiveness of training and safety protocols. A comparison with international data corroborated the low exposure levels. Clinical training is essential for radiography students, and this study highlights the success of safety protocols in minimising occupational radiation exposure. Continuous monitoring and education are crucial to sustaining these positive outcomes. [ABSTRACT FROM AUTHOR]

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Background: Calibration of Thermo Luminescent Dosimetry (TLD) in eye lens dosimeter requires a standard phantom. The use of anthropomorphic phantoms in calibration needs evaluation. Objective: This study aimed to analyze the angular response of the TLD on the fabricated 3D anthropomorphic head phantom and Computerized Imaging Reference Systems (CIRS)- Computed Tomography (CT) dose phantom as a standard phantom irradiated with Cs-137 and to compare the absorbed dose and linear attenuation for both phantoms. Hp(3) analysis, conversion coefficient (hpK(3)), and calibration factor (CF) are also investigated.Material and Methods: In this experimental study, the fabricated 3D printed anthropomorphic head phantom was analyzed using polylactic acid (PLA) with the skull and then filled with the artificial brain and cerebrospinal fluid (CSF) as a test phantom. TLD-700H and TLD Reader Harshaw 6600 plus were used to analyze the angular response of Cs-137 radiation and to determine the absorbed dose and linear attenuation coefficient of test and standard phantoms. Results: The effect of the angle of radiation source towards TLD reading at the anthropomorphic head phantom has a similar value to the standard phantom with a calibration factor ranging from 0.82 to 1. The absorbed dose measurement and the linear attenuation coefficient of the anthropomorphic head phantom with the standard phantom have different values of 2.52 and 3.78%, respectively. Conclusion: The fabricated 3D printed anthropomorphic head phantom has good potential as an alternative to standard phantoms for TLD calibration in eye lens dosimeter.

Abstract Background The high susceptibility of the hippocampus region to radiation injury is likely the causal factor of neurocognitive dysfunctions after exposure to ionizing radiation. Repetitive exposures with even low doses have been shown to impact adult neurogenesis and induce neuroinflammation. We address the question whether the out-of-field doses during radiotherapy of common tumour entities may pose a risk for the neuronal stem cell compartment in the hippocampus. Methods The dose to the hippocampus was determined for a single fraction according to different treatment plans for the selected tumor entities: Point dose measurements were performed in an anthropomorphic Alderson phantom and the out-of-field dose to the hippocampus was measured using thermoluminescence dosimeters. Results For carcinomas in the head and neck region the dose exposure to the hippocampal region for a single fraction ranged from to 37.4 to 154.8 mGy. The hippocampal dose was clearly different for naso-, oro- and hypopharynx, with maximal values for nasopharynx carcinoma. In contrast, hippocampal dose levels for breast and prostate cancer ranged between 2.7 and 4.1 mGy, and therefore significantly exceeded the background irradiation level. Conclusion The mean dose to hippocampus for treatment of carcinomas in the head and neck region is high enough to reduce neurocognitive functions. In addition, care must be taken regarding the out of field doses. The mean dose is mainly related to scattering effects, as is confirmed by the data from breast or prostate treatments, with a very different geometrical set-up but similar dosimetric results.

Background: This study aimed to investigate the occupational exposure of undergraduate radiography students to ionising radiation and evaluate the effectiveness of safety protocols and training in reducing radiation exposure. Methods: This study tracked undergraduate radiography students from the University of Sharjah, UAE, using thermoluminescent dosimeters (TLDs) from 2015 to 2023. TLD readings were conducted every 15 weeks during 384 h of clinical placement. This study encompassed various radiographic procedures, and the TLDs were used to measure shallow (HP (0.07)) and deep doses (HP (10)). Results: A data analysis from 599 dosimeters revealed an average of 74 students annually. The average effective doses for HP (10) and HP (0.07) were 0.227 mSv and 0.222 mSv, respectively. These doses were well-below the recommended annual limits. Conclusion: This study’s results indicated that radiography students’ occupational radiation exposure during clinical training was within the safe limits, demonstrating the effectiveness of training and safety protocols. A comparison with international data corroborated the low exposure levels. Clinical training is essential for radiography students, and this study highlights the success of safety protocols in minimising occupational radiation exposure. Continuous monitoring and education are crucial to sustaining these positive outcomes.

Introduction: The present study aimed to assess the reduction of breast surface dose, breast radiation-induced cancer incidence, and mortality risks when the lead apron shielding was positioned on the chest regions during head computed tomography (CT). Material and Methods: In this study, routine head CT scans were performed on 28 female patients with a mean body mass index (BMI) of 25.2 ± 2.8 kg/m2. The common lead aprons (0.5 mm thicknesses) were folded and positioned in the chest regions. The breast surface doses were measured using six thermoluminescent dosimeters (TLD-100), three TLDs were located above the apron and three ones positioned under the apron. Breast radiation-induced cancer incidence and mortality risks were estimated using the Biological Effects of Ionizing Radiation (BEIR-VII) model. Finally, the measured doses and cancer/mortality risks were compared using Paired sample T-Test in SPSS software. Results: The breast surface doses under and over the apron were obtained at 0.18±0.06 and 0.49±0.13 mGy, respectively, (P-value

Background: The high susceptibility of the hippocampus region to radiation injury is likely the causal factor of neurocognitive dysfunctions after exposure to ionizing radiation. Repetitive exposures with even low doses have been shown to impact adult neurogenesis and induce neuroinflammation. We address the question whether the out-of-field doses during radiotherapy of common tumour entities may pose a risk for the neuronal stem cell compartment in the hippocampus. Methods: The dose to the hippocampus was determined for a single fraction according to different treatment plans for the selected tumor entities: Point dose measurements were performed in an anthropomorphic Alderson phantom and the out-of-field dose to the hippocampus was measured using thermoluminescence dosimeters. Results: For carcinomas in the head and neck region the dose exposure to the hippocampal region for a single fraction ranged from to 37.4 to 154.8 mGy. The hippocampal dose was clearly different for naso-, oro- and hypopharynx, with maximal values for nasopharynx carcinoma. In contrast, hippocampal dose levels for breast and prostate cancer ranged between 2.7 and 4.1 mGy, and therefore significantly exceeded the background irradiation level. Conclusion: The mean dose to hippocampus for treatment of carcinomas in the head and neck region is high enough to reduce neurocognitive functions. In addition, care must be taken regarding the out of field doses. The mean dose is mainly related to scattering effects, as is confirmed by the data from breast or prostate treatments, with a very different geometrical set-up but similar dosimetric results. [ABSTRACT FROM AUTHOR]

Background: The dose values obtained from procedures of diagnostic radiology are relatively low. To accurately and precisely measure the dose values in this dose range, it is necessary to know the characteristics of dosimeters.Objective: The aim of this study was to evaluate several thermoluminescent characteristics of GR-200, TLD-700H and TLD-100 for low dose measurement.Material and Methods: In this experimental study, linearity, repeatability, dose rate and photon energy dependence of different TLD materials were investigated in a 0.05-10 mGy range dose. It is noteworthy that the data obtained from TLD-100 were considered as reference and the data obtained from two other types of TLDs were compared with them. Results: For all three types of TLD materials, there are linear relations between absorbed dose values to TLDs and their responses. TLD-100 and TLD-700H have very low sensitivity than GR-200. For GR-200 and TLD-100, the coefficients of variation values (%) are 3.00% and 2.01%, respectively, that these values are within the tolerance limit (

The paper presents results of on-ground (pre-flight) calibrations and flight tests (cross-calibration and in situ measurements) of the new, Modified PILLE-ISS Dosimeters with reduced shielding, developed for the radiation monitoring of astronauts during their extravehicular activity (EVA) on board the International Space Station (ISS). The smaller dimensions and weight of the modified thermoluminescent dosimeter allows ergonomic and safe use during EVA, when the dosimeter kit is worn in the outer pocket of a spacesuit. The special design of the detector housing makes it possible to estimate the dose to the astronaut's skin during EVA more accurately. Both pre-flight calibration with high-energy protons and on-board cross-calibration at ISS showed that the variability of the relative sensitivities does not exceed (5–10)% for any of the Modified PILLE-ISS Dosimeters. The additional dose received by astronauts during ISS EVAs in 2023 was in the range (0.37–0.75) mGy (in water) based on the measurements. The corresponding dose rate outside ISS is consistent with the previous readings of other dosimetric equipment installed on the outer surface of space station. • The Hungarian PILLE-ISS onboard thermoluminescent system is upgraded for the EVA dose assessment. • Calibration with high-energy protons showed low deviation in dose-response (less than 10%) for any dosimeter. • On-board cross-calibration at ISS showed that variability of relative sensitivities does not exceed 10% for any dosimeter. • The additional dose received by astronauts during ISS EVAs in 2023 was in the range 0.37–0.75 mGy (in water). • The measured dose rate inside and outside ISS is consistent with the readings of other dosimetric equipment. [ABSTRACT FROM AUTHOR]

Objectives: Vascular and interventional radiology procedures are characterized by high exposure of personnel to ionizing radiation. This study assessed the exposure of medical personnel to ionizing radiation during vascular radiology and mechanical thrombectomy procedures., Material and Methods: During vascular radiology procedures, the exposure of 4 groups of workers participating in the procedures was analyzed, i.e., the main operating physician, an assistant physician, a sterile nurse, and a nurse. Measurements of exposure to ionizing radiation were performed using thermoluminescent dosimetry., Results: The registered effective dose during 1 treatment in individual groups is, respectively: mean (M) ± standard deviation (SD) 75±15 μSv, 24±5 μSv, 13±3 μSv, and 8±2 μSv. During mechanical thrombectomy, the operating physician receives an effective dose of M±SD 9±2 μSv. The equivalent doses for the lenses for the operating physician and the doctor assisting during vascular radiology procedures are M±SD 1419±285 μSv and 987±198 μSv, respectively, and for the hands, including the left and right hands, M±SD 4605±930 μSv, 1420±284 μSv, 1898±380 μSv, 1371±274 μSv., Conclusions: If the principles of optimizing radiological protection are not applied during vascular radiology procedures, the permissible dose limits and operational limits equivalent to doses to lenses and hands may be exceeded. Exposure during vascular radiology procedures is comparable to exposure during nuclear medicine procedures in terms of the use of glucose labeled with radioactive fluorine. Int J Occup Med Environ Health. 2024;37(4):403-10., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

The current work was going to study the dosimetric properties of Egyptian muscovite minerals irradiated with β-rays using the thermoluminescence technique (TL). The analysis of the TL glow curves was done using the (T m  - T stop ) and the initial rise methods. The deconvolution of the muscovite glow curves was analyzed to have eight superimposed trapping peaks. These trapes were located at 0.72, 0.80, 0.98, 1.09, 1.19, 1.30, 1.50, and 1.59 eV. Muscovite samples were studied at doses up to 330 Gy and exhibited good linearity in relation to beta radiation. The kinetic parameters, sensitivity, and dosimetric characteristics were evaluated. High accuracy was achieved through the repeatability of TL measurements., (© 2024 John Wiley & Sons Ltd.)

Background: The paper presents the results of dosimetric measurements routinely performed by the Radiation Protection Department of the Nofer Institute of Occupational Medicine (NIOM) in Łódź in 2022 for people occupationally exposed to X and γ radiation., Material and Methods: The evaluation of the effective dose as part of individual dosimetry was provided using the film or thermoluminescent dosimetry (TLD). Additionally, based exclusively on the TLD method, measurements of the ambient dose equivalent H*(10) and personal dose equivalents Hp(0.07) and Hp(3) were performed. In 2022, the dosimetric service of the Radiological Protection Department of the NIOM covered >30 000 workers employed in >4500 laboratories (mainly health care departments). All measurements were performed in accordance with accredited research procedures (number AB 327)., Results: In 2022, the average annual dose of Hp(10) was equal to 0.26 mSv, whereas Hp(0.07) measured using ring and wrist dosimetry was equal to 0.63 mSv and 0.78 mSv, respectively. In turn, the average Hp(3) value was 0.21 mSv. In 2022, there was not a single case of exceeding the annual dose limit among people measured by the NIOM., Conclusions: The data collected in the "Dosimetry" database of the NIOM and a detailed analysis of annual doses received by people occupationally exposed to ionizing radiation indicate a well-functioning radiological protection system in Poland. Med Pr Work Health Saf. 2024;75(5)., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

Fluoroscopic examinations like Endoscopic Retrograde Cholangiopancreatography (ERCP) and Percutaneous Transhepatic Cholangiography (PTC) are fundamental in diagnosing and treating hepatobiliary diseases. However, these procedures expose patients to significant radiation, highlighting the need for a detailed assessment of the radiation doses received by critical organs. The study's primary objective is to determine the experimental doses received by critical organs in patients undergoing these procedures. This study utilized an Alderson RANDO phantom outfitted with Thermoluminescent Dosemeters (TLDs) to experimentally measure the radiation doses received by various organs during ERCP and PTC procedures. This method provided direct and accurate data on organ-specific radiation exposure, contrasting with the traditional approach of relying on theoretical simulations. The analysis revealed that PTC generally results in higher radiation doses to organs compared to ERCP. Critical organs, such as the thyroid, spleen, liver, pancreas, ovaries, and uterus, were exposed to varying levels of radiation, with the thyroid and spleen receiving particularly high doses in PTC. The study also demonstrated that the per-minute radiation exposure was consistently higher in PTC across all examined organs. The study's findings underscore the significant radiation exposure associated with ERCP and PTC, with PTC posing a greater risk. Understanding these exposure levels is crucial for clinical decision-making, particularly when considering patients' pre-existing conditions and sensitivity to radiation. The study highlights the need for clinicians to carefully weigh the benefits of ERCP and PTC against the potential radiological risks. It suggests a preference for ERCP in situations where radiation exposure needs to be minimized. Furthermore, the findings advocate for ongoing advancements in medical imaging techniques to reduce radiation exposure, emphasizing the importance of patient safety in fluoroscopic examinations. This research contributes significantly to informed clinical decision-making, ensuring that the selection of diagnostic and therapeutic procedures aligns with the best interest of patient health and safety., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Radiopharmacy staff members are subject to extremity radiation doses, particularly to the fingertips. Dosemeters, such as, thermoluminescent detectors (TLDs) are currently used for monitoring fingertip doses. This study aimed to use real-time dosemeters to monitor radiopharmacy extremity doses to identify specific procedural steps associated with higher fingertip doses and, subsequently, reduce dose through promotion of optimised radiation protection practises. Five radiopharmacy operators were monitored using an ED3 active extremity dosemeter with a detector attached to each tip of the index fingers. Dose rate and accumulated dose data were matched to the handled radioactivity data, of 99m Tc-labelled radiopharmaceuticals only, with the dose per activity ( μ Sv MBq -1 ) calculated for each step. Once baseline dose data was established, an educational session identified technique adjustments toward improved radiation protection. A subsequent monitored session was undertaken with the dose data compared to quantify changes in operator doses. Radiopharmacy steps which significantly contributed to extremity doses were identified. The average accumulated dose per activity across all procedural steps for the 99m Tc-labelled radiopharmaceuticals for all operators before the educational session was 0.042 ± 0.045 μ Sv MBq -1 and 0.042 ± 0.041 μ Sv MBq -1 ( n = 89) for non-dominant and dominant index fingertips, respectively, and 0.030 ± 0.044 μ Sv MBq -1 and 0.031 ± 0.032 μ Sv MBq -1 ( n = 97), respectively, afterwards. Overall, there was an average 40.7% reduction in the total extremity dose received after the educational session. Real-time electronic extremity dosemeters for monitoring radiopharmacy extremity dose presented as a useful tool for incorporation into radiation protection education and training, towards optimised radiopharmacy technique., (© 2024 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Background: The risk of radiation exposure in the surgical operating room (OR) and/or catheterization laboratory is now well established. Complex endovascular procedures often require multiple approaches and different positioning of the staff members around the patient, potentially increasing the levels of radiations exposure. Our goal was to evaluate the levels of radiation exposure of the members of the staff during endovascular aortic procedures in order to propose radioprotection optimization., Methods: We included 41 aortic endovascular procedures out of 114 procedures performed between January 12, 2014, and August 31, 2015, including 24 standard endovascular aortic aneurysm repair (EVAR), 7 EVAR with iliac branch (EVARib), 8 complex fenestrated/branched EVAR (F/B EVAR), and 2 thoracic EVAR (TEVAR). Procedures were performed in an OR equipped with a carbon fiber table and a mobile fluoroscopy C-arm. We collected the usual dosimetry data given by the C-arm as well as the patient's peak skin dose (PSD). In all staff members, radiation exposure was measured with thermoluminescent chip dosimeters placed on both temples, on posterior sides of both hands, and on both lower legs., Results: PSD levels were low for EVAR because 24 patients had values below the reading threshold. PSD significantly increased with more complex procedures. Main operator (MO) received the higher level of irradiation on whole body, hands, and ankles. Eye lenses irradiation was higher on both assistant operators (AOs). Other members received low levels of irradiation. We found a high ranges of radiation exposure with a high risk of exposure for the AO, mainly for F/B EVAR and EVARib., Conclusions: Even if all personal protections are used, staff positioning is a major point that must be considered. If MO is supposed to be the most exposed to X-rays, specific conditions of positioning of the AO may be at risk of exposure., (Copyright © 2024. Published by Elsevier Inc.)

Background: Radiation is an integral part of routine medical practice, but it carries a risk to the health of medical staff. Hence, it should be assessed periodically. The study's goal was to quantify the levels of radiation exposure for medical staff at King Faisal Medical Complex (KFMC), Taif City Saudi Arabia, and to assess their radiation protective procedures in practice., Methods: The study looked at the thermoluminescence dosimeters (TLDs) records of 50 medical professionals who were exposed to radiation while working at KFMC from 2019 to 2020 in Taif city, Saudi Arabia. In Riyadh, radiation exposure is read from skin TLDs using Harshaw model 6600 plus detectors. The Excel software was utilized to process the obtained data for calculating effective doses. A questionnaire was also distributed to the medical staff to assess their radiation protection procedures. The Statistical Package for Social Sciences (SPSS) program version 23 was used to analyze the obtained data., Results: The mean annual effective doses of the medical staff in 2019 and 2020 were determined to be 1.14 mSv and 1.4645 mSv, respectively, with no significant difference in effective doses between males and females in either year. The socio-demographic features of the medical personnel were examined, and the findings revealed that the majority of participants were male radiological technologists. The rate of adherence to radiation protection techniques was 68%, with a normally distributed dispersal. The amount of adherence varied significantly depending on nationality, occupation, and academic qualification., Conclusion: According to the research, the mean annual effective dosage for medical professionals at KFMC was significantly below the recommended level, indicating satisfactory compliance with the ALARA radiation safety concept., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study provides a comprehensive evaluation of the occupational radiation exposure faced by healthcare professionals during Endoscopic Retrograde Cholangiopancreatography (ERCP) procedures. Utilizing an anthropomorphic RANDO phantom equipped with Thermoluminescent Dosimeters (TLDs), we replicated ERCP scenarios to measure radiation doses received by medical staff. The study meticulously assessed radiation exposure in various corresponding body regions typically occupied by medical staff during ERCP, with a focus on eyes, thyroid, hands, and reproductive corresponding organ regions. The findings revealed significant variations in radiation doses across different body parts, highlighting areas of higher exposure and underscoring the need for improved protective measures and procedural adjustments. The effective radiation doses were calculated using standard protocols, considering the varying levels of protection offered by lead aprons and thyroid shields. The results demonstrate the substantial radiation exposure experienced by healthcare staff, particularly in regions not adequately shielded. This study emphasizes the necessity for enhanced radiation safety protocols in clinical settings, advocating for advanced protective equipment, training in radiation safety, and the exploration of alternative imaging modalities. The findings have crucial implications for both patient and staff safety, ensuring the continued efficacy and safety of ERCP and similar interventional procedures. This research contributes significantly to the field of occupational health and safety in interventional radiology, providing vital data for the development of safer medical practices., (© 2024. The Author(s) under exclusive licence to Japan Radiological Society.)

Objective: In order to understand the complete scenario of the effectiveness of radiation protection practice in the workplace, especially in the industrial radiography and also to analyze the trends with other related studies, epidemiological studies and legal purposes, the assessment and register of the effective dose plays a significant role. Therefore, efforts have been given in the assessment of collective effective dose, mean effective dose, prediction of lifetime cancer risk, and contribution of different age group workers in the collective effective dose. Methods: The occupational radiation exposures for 472 workers were investigated in industrial radiography throughout Bangladesh from 2015 to 2018 by using thermoluminescent dosimeter (TLD). By using a Harshaw TLD reader (Model-4500), the effective dose was measured in a quarterly basis throughout the year. Based on the value of personal dose equivalent Hp(10), database was prepared and recorded. Results: The collective effective dose was 36.1, 40.7, 28.8 and 37.5 man·mSv among 105, 102, 100 and 165 radiation workers in 2015, 2016, 2017 and 2018, respectively. The maximum effective dose received by radiation workers was 6.0, 7.1, 6.9 and 19.9 ​mSv in 2015, 2016, 2017 and 2018, 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). Conclusion: This kind of monitoring would help to construct a national database that will be used by the end users to improve their implementation of optimization in occupational radiation protection in industrial radiography.

Background: Computed tomography (CT) is a routine procedure for diagnosing using ionization radiation which has hazardous effects especially on sensitive organs. Objective: The aim of this study was to quantify the dose reduction effect of lead apron shielding on the testicular region during routine chest CT scans.Material and Methods: In this measurement study, the routine chest CT examinations were performed for 30 male patients with common lead aprons folded and positioned in testis regions. The patient’s mean body mass index (BMI) was 26.2 ± 4.6 kg/m2. To calculate the doses at testis region, three thermoluminescent dosimeters (TLD-100) were attached at the top surface of the apron as an indicator of the doses without shielding, and three TLDs under the apron for doses with shielding. The TLD readouts were compared using SPSS software (Wilcoxon test) version 16. Results: The radiation dose in the testicular regions was reduced from 0.46 ± 0.04 to 0.20 ± 0.04 mGy in the presence of lead apron shielding (p < 0.001), the reduction was equal to 56%. Furthermore, the heritable risk probability was obtained at 2.0 ×10-5 % and 4.6 ×10-5 % for the patients using the lead apron shield versus without shield, respectively. Conclusion: Applying common lead aprons as shielding in the testis regions of male patients undergoing chest CT scans can reduce the radiation doses significantly. Therefore, this shield can be recommended for routine chest CT examinations.

Introduction: In various radiotherapy techniques for breast cancer, the inclusion of internal mammary nodes (IMNs) in the target volume is important for selecting the most appropriate technique. This study aimed to compare three radiotherapy techniques with the inclusion of IMNs regarding the dose homogeneity index (DHI) of regional lymph nodes and the chest wall, besides the dose received by the heart and the left lung. Material and Methods: Three radiotherapy techniques were planned for CT imaging of the RANDO phantom, including the wide tangent (WT); oblique parasternal photon (OPP); and oblique parasternal electron (OPE) techniques. The doses reaching the contoured organs were compared between the three techniques, using the data gathered from the thermoluminescent dosimetry and treatment planning system. Results: The OPE technique produced a lower absorbed dose for the left IMNs, compared to the other two techniques. In the OPP technique, the dose received by the left lung was higher than its tolerance, while the lung dose in the OPE technique was slightly lower than the WT technique. The absorbed dose by the heart was the lowest in the WT technique; also, the DHI value was better for this technique than the other two techniques. Conclusion: The WT technique showed better results regarding the dose homogeneity distribution of IMNs and the chest wall, as well as protection of organs at risk.

Samples of crystalline cubic phased ceramics based on (Zr 1-х Hf х) 0.82 Y 0.17 Eu 0.01 O 1.91 with different contents of hafnium (х = 0; 0.21; 0.50; 0.77; 1) were synthesized. The synthesis conditions were chosen to avoid the possible formation of a minor tetragonal phase. The average grain size was 2–5 microns. The structural parameters of ceramics, their band gap, luminescent and thermoluminescent properties were studied depending on the hafnium content. It was shown that single-phase sample with calculated formula ((Zr 0.77 Hf 0.23) 0.82 Y 0.17 Eu 0.1)O 1.91 demonstrated the highest cathodoluminescent intensity upon excitation by electrons. It was found that thermoluminescent properties of ceramics with hafnium content of х = 0.50–0.77 range are prospective for application in thermodosimetry. The highest luminescence yield was observed in such samples. [Display omitted] • YSZ-YSH ceramics form a solid solution over the entire concentration range. • Сeramics mainly consists of large grains (2–5 microns). • Samples with the ratio N Hf /(N Hf +N Zr) from 0.2 to 0.8 has the highest quantum yield. • Samples with N Hf /(N Hf +N Zr)= 0.50 and 0.77 have a dosimetric thermoluminescent peak. [ABSTRACT FROM AUTHOR]

Early works that used thermoluminescent dosimeters (TLDs) to measure absorbed dose from alpha particles reported relatively high variation (10%) between TLDs, which is undesirable for modern dosimetry applications. This work outlines a method to increase precision for absorbed dose measured using TLDs with alpha-emitting radionuclides by applying an alpha-specific chip factor (CF) that individually characterizes the TLD sensitivity to alpha particles. Variation between TLDs was reduced from 21.8% to 6.7% for the standard TLD chips and 7.9% to 3.3% for the thin TLD chips. It has been demonstrated by this work that TLD-100 can be calibrated to precisely measure the absorbed dose to water from alpha-emitting radionuclides. • TLDs used to measure absorbed dose from alpha particles have shown high variation. • 5.304 MeV alpha particles have a range of only 21 μm in TLDs. • Alpha Particles interact with a small percentage of the total TLD sensitive volume. • Alpha-Specific chip factors characterize TLD sensitivity to alpha particles. • TLD precision was increased when alpha-specific chip factors were applied. [ABSTRACT FROM AUTHOR]

Background: To investigate dose distribution of the 5cm spherical applicator of the INTRABEAM™ intraoperative radiation therapy (IORT) device via thermoluminescence dosimeters (TLDs) and Radiographic films. Independent dose distribution assessment of IORT devices is considered important. Several methods are described for this purpose, including TLDs and films. However, Radiographic films are not routinely used. Materials and methods: Twenty TLDs were used for depth dose measuring and evaluating the isotropy in water. Additionally, the isotropy was assessed separately via Radiographic films in air by drawing isodose curves. Results: TLD measurements showed a steep dose decline which the relative average dose of 0.94 at the applicator surface reduced to 0.32, 0.13, and 0.07 at 1, 2, and 3 cm depths in water, respectively. Some remarkable isodose curves prepared using Radiographic films showed forward anisotropy of the 5 cm applicator. Conclusion: A very steep dose decline and approximately isotropic dose distribution of the 5 cm applicator were observed via TLD measurements. Radiographic films showed acceptable potential for drawing dose distribution maps. However, they should be applied in more various radiation setups to be implemented more confidently. [ABSTRACT FROM AUTHOR]

Background: The dose values obtained from procedures of diagnostic radiology are relatively low. To accurately and precisely measure the dose values in this dose range, it is necessary to know the characteristics of dosimeters. Objective: The aim of this study was to evaluate several thermoluminescent characteristics of GR-200, TLD-700H and TLD-100 for low dose measurement. Material and Methods: In this experimental study, linearity, repeatability, dose rate and photon energy dependence of different TLD materials were investigated in a 0.05- 10 mGy range dose. It is noteworthy that the data obtained from TLD-100 were considered as reference and the data obtained from two other types of TLDs were compared with them. Results: For all three types of TLD materials, there are linear relations between absorbed dose values to TLDs and their responses. TLD-100 and TLD-700H have very low sensitivity than GR-200. For GR-200 and TLD-100, the coefficients of variation values (%) are 3.00% and 2.01%, respectively, that these values are within the tolerance limit (<7.5%). However, this value for TLD-700H is 10.85% which it is more than the reported tolerance limit. Furthermore, remarkable effects of dose rate and photon energy dependence on the responses of GR-200 are not observed in a 0.5-4 mGy dose range; nevertheless, remarkable effects of dose rate and photon energy dependence on the responses of TLD-100 and TLD- 700H are found in this dose range. Conclusion: The evaluated thermoluminescent characteristics for GR-200 are better than two other types of TLDs (TLD-100 and TLD-700H) for low dose values. [ABSTRACT FROM AUTHOR]

Objective: By simulating a fluoroscopic-guided vascular intervention, two differently designed radiation safety glasses were compared. The impacts of changing viewing directions and body heights on the eye lens dose were evaluated. Additionally, the effect of variable magnification levels on the arising scattered radiation was determined. Methods: A phantom head, replacing the operator's head, was positioned at different heights and rotated in steps of 20° in the horizontal plane. Thermoluminescent dosimeters (TLD), placed in the left orbit of the phantom, detected eye lens doses under protected and completely exposed conditions. In a second step, radiation dose values with increasing magnification levels were detected by RaySafe i3 dosimeters. Results: Changing eye levels and head rotations resulted in a wide range of dose reduction factors (DRF) from 1.1 to 8.5. Increasing the vertical distance between the scattering body and the protective eyewear, DRFs markedly decreased for both glasses. Significant differences between protection glasses were observed. Increasing magnification with consecutively decreasing FOV size variably reduced the dose exposure to the eye lens between 47 and 83%, respectively. Conclusion: The safety glasses in the study effectively reduced the dose exposure to the eye lens. However, the extent of the protective effect was significant depending on eye levels and head rotations. This may lead to a false sense of safety for the medical staff. In addition, the application of magnification reduced the quantity of scattering dose significantly. To ensure safe working in the Cath-lab, additional use of protective equipment and the differences in design of protective eyewear should be considered. Key Points: • Eye lens dose changes with physical size of the interventionist and viewing direction. • The use of magnification during fluoroscopic-guided interventions reduces scattered radiation. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is the most common cancer among women. Considering the fact that a high dose is delivered in a single fraction of IORT, the evaluation of the dose at sensitive organs like thyroid is necessary. Objective: The current study has aimed to evaluate the received dose to thyroid lobes in the breast IORT technique.Material and Methods: A total of 49 women with breast cancer undergoing IORT were enrolled in this cross-sectional study with census sampling. Immediately after tumor resection, a single dose of 20 Gray at the applicator surface was delivered using 50KV X-ray by an Intrabeam machine. The thyroid dose was detected using thermoluminescent detectors (TLD) 100 at the mid-thyroid line, left and right lobes. Results: The dose at the right and left lobes of the thyroid gland as well as the mid-thyroid line was found to be 40.18±35.44 mGy, 35.50±27.32 mGy, and 40.61±32.47 mGy, respectively. The right lobe received a significantly higher absorbed dose compared to the left lobe when the right breast was under IORT treatment. The same trend was seen with the left lobe and left breast under IORT treatment (P=0.0001 and P=0.018, respectively). The applicator size showed non-significant effects on the absorbed dose at the thyroid gland. Also, the applicator depth had a non-significant inverse effect on thyroid dose. Conclusion: According to our findings, the absorbed dose at each thyroid lobe depends on the under-treatment side as well as the applicator size and depth (applicator upper surface distance from the skin).

Passive solid state dosimeters, such as thermoluminescence dosimeters, provide integrated measurement of the total dose and are widely used in environmental monitoring programs. The objective of this paper is to provide a comprehensive review on the use of thermoluminescent dosimetry methods for monitoring radiation dose in the environment. The article presents the part of the research results of the project PREPAREDNESS (EMPIR 2016 call for Metrology for Environment joint research project) with a particular objective to harmonize procedures used by dosimetry services, relevant authorities and Institutes across the Europe. To achieve this, different monitoring routines that are based on passive environ mental dosimetry methods are investigated. Differences in performing specific steps such as preheating, reading, annealing, minimizing fading, and others, are analyzed. The investigation was performed by means of qualitative literature review that showed the lack of information about specific steps. The conclusion of this work is that thermoluminescent dosimetry measurement system has to be type-tested even though the testing procedure is complicated. In addition to this, control dosimeters should be introduced, International Organization for Standardization protocols should be followed during calibration, and finally, parameters influencing the measurement uncertainty have to be identified and well understood in order to pro duce ac cu rate dose measurement results.

Purpose: The risk of inducing cancer to patients undergoing CT examinations has motivated efforts for CT dose estimation, monitoring, and reduction, especially among pediatric population. The method investigated in this study is Acuros CTD (Varian Medical Systems, Palo Alto, CA), a deterministic linear Boltzmann transport equation (LBTE) solver aimed at generating rapid and reliable dose maps of CT exams. By applying organ contours, organ doses can also be obtained, thus patient‐specific organ dose estimates can be provided. This study experimentally validated Acuros against measurements performed on a clinical CT system using a range of physical pediatric anthropomorphic phantoms and acquisition protocols. Methods: The study consisted of (1) the acquisition of dose measurements on a clinical CT scanner through thermoluminescent dosimeters (TLDs), and (2) the modeling in the Acuros platform of the measurement set up, which includes the modeling of the CT scanner and of the anthropomorphic phantoms. For the measurements, 1‐year‐old, 5‐year‐old, and 10‐year‐old anthropomorphic phantoms of the CIRS ATOM family were used. TLDs were placed in selected organ locations such as stomach, liver, lungs, and heart. The pediatric phantoms were scanned helically with the GE Discovery 750 HD clinical scanner for several examination protocols. For the simulations in Acuros, scanner‐specific input, such as bowtie filters, overrange collimation, and tube current modulation schemes, were modeled. These scanner complexities were implemented by defining discretized X‐ray beams whose spectral distribution, defined in Acuros by only six energy bins, varied across fan angle, cone angle, and slice position. The images generated during the CT acquisitions were used to create the geometrical models, by applying thresholding algorithms and assigning materials to the HU values. The TLDs were contoured in the phantom models as sensitive cylindrical volumes at the locations selected for dosimeters placement, to provide dose estimates, in terms of dose per unit photon. To compare measured doses with dose estimates, a calibration factor was derived from the CTDIvol displayed by the scanner, to account for the number of photons emitted by the X‐ray tube during the procedure. Results: The differences of the measured and estimated doses, in terms of absolute % errors, were within 13% for 153 TLD locations, with an error of 17% at the stomach for one study with the 10‐year‐old phantom. Root‐mean‐squared‐errors (RMSE) across all TLD locations for all configurations were in the range of 3%–8%, with Acuros providing dose estimates in a time range of a few seconds up to 2 min. Conclusions: An overall good agreement between measurements and simulations was achieved, with average RMSE of 6% across all cases. The results demonstrate that Acuros can model a specific clinical scanner despite the required discretization in spatial and energy domains. The proposed deterministic tool has the potential to be part of a near real‐time individualized dosimetry monitoring system for CT applications, providing patient‐specific organ dose estimates. [ABSTRACT FROM AUTHOR]

Background: Thermoluminescence dosimetry(TLD) has been known as one of the most effective methods for dose estimation in diagnostic radiology. Orthopantomogram (OPG) imaging is used by many dentists, oral and maxillofacial surgeons as an effective tool for choosing an appropriate treatment plan. Objective: This study aims to measure the entrance skin dose and the dose values received by different head and neck organs in OPG imaging using TLD dosimeters (TLD-100).Material and Methods: In this experimental study, the entrance skin dose and doses of various organs during imaging were measured by TLD dosimeters inside and on the surface of the Rando-Phantom. Doses to various organs, including thyroid, eye, esophagus, parotid and sublingual and submandibular salivary glands were measured. The measurements were repeated twice, and the dose values obtained in the two steps were compared. Results: Based on the results obtained in this study, the minimum dose values were found in Esophagus; 65.81, and 59.31 µGy, respectively. The maximum organ dose value was found for left parotid glands, 3842.42, and 3399.58 for the two measurements, respectively. Conclusion: The results show that the dose values can vary based on devices, exposure conditions, and TLD positioning.

Abstract Positioning and immobilization tools are considered essential components of radiotherapy treatments to guarantee that the planned dose distribution can be efficiently reached. However, the benefits brought by their use are met by an apparent increase in the patient skin entrance dose. In the current study, we evaluated the dose surface effects provoked by the use of immobilization thermoplastic masks in head and neck radiotherapy treatments, carried out using a 6‐MV linear accelerator beam. The study was carried out using an anthropomorphic head–neck phantom and three dosimetric techniques: (i) thermoluminescent dosimetry (TL); (ii) radiochromic film dosimetry; and (iii) computational simulation using the pencil beam convolution (PBC) method. For calibration purposes, TLD chips and radiochromic (EBT3) small 2.0‐cm2 strip dosimeters were positioned between two virtual solid water plates, and exposed to absorbed doses ranging from 25 to 200 cGy. The use of an anthropomorphic head–neck phantom allows the dose variation in non‐flat surfaces to be taken into account. TLD chips, positioned on the surface of the supraclavicular fossa anatomical region, covered with a thermoplastic mask, detected an entrance skin dose that was approximately 38.4% higher than that measured without a mask. The EBT3 dosimeters, averaged among all strips used, also detected a medium increase of 58.6%. Both TLD and EBT3 detected increased doses for all measured points, and measured similar averaged surface doses without the use of immobilization masks; that is, 50.5% for EBT3 and 53.7% for TLD‐100. The pencil beam convolution simulation results suggested an increase for most of the measured points; however, no increased, and in some cases even decreased, doses were observed. The surface dose data of three other commercial thermoplastic masks irradiated in a solid water phantom are also provided.

Background: The purpose of this study was to evaluate the effect of shields in imposed radiation dose to gonads in anterior-posterior (AP) and lateral views of lumbosacral radiography using digital radiography (DR) and computerized radiography (CR) methods. Materials and Methods: Sixty patients who were suspected to AP and lateral view of lumbosacral radiography were included in this study. The patients were exposed with and without shields which have 0.25 mm thickness. This study also compared the imposed dose to gonads for one and two plates of shields with none shields situation. Measurement of the radiation dose was performed using thermo luminescence dosimeters on the surface of the gonads. Furthermore, the absolute and excess relative risk (ERR) of biological abnormalities was estimated in the above-mentioned method using the BEIR VII model. Results: The mean dose of the DR method (10.14 ± 0.27) for the AP view was significantly lower than CR (32.43 ± 0.17) with and without shields. In addition, the imposed dose to gonads in the lateral view of DR (6.41 ± 0.47) was lower compared to CR (9.38 ± 0.14). Furthermore, the mean imposed dose to gonads for one and two pate shields of DR was lower than CR. Moreover, the excess relative risk to gonads in the AP for DR was lower compared to CR in all mentioned situations. Conclusion: Lumbosacral radiography is suggested to be performed by DR systems, due to the lower imposed dose and ERR to the gonads. Moreover, using shields may lead to decrease of scatter rays and also ERR of the gonads.

The annual occupational doses for workers at the Ghana Research Reactor-1 facility were assessed for the period 2018-2021. The dose records of monitored staff were retrieved and analysis done for dose distribution and collective effective doses. Thermoluminiscent dosimeters were used to monitor the occupational exposures. The dosimeters were evaluated for the cumulative radiation dose levels using the Harshaw 6600 TLD reader system. Annual dose of 1.52 mSv/year was the maximum acquired by an individual. An annual average effective dose range of 0.20-1.36 mSv was determined for all workers. The annual total collective effective dose was established to be in the range of 0.40-10.08 man-Sv. The 20 mSv annual limit for occupational exposure was not exceeded for monitored workers. The assessment shows that the GHARR-1 facility, in terms of radiation health effects, is a favorable environment for workers since exposures are mostly below occupational exposure limit., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Since 2011, the International Commission on Radiological Protection (ICRP) has recommended an annual eye lens dose limit of 20 mSv for radiation workers, averaged over 5 years, with no year exceeding 50 mSv. However, limited research has been conducted on dose rate conversion coefficients (DCCs) for direct contamination of the eye., Purpose: This study aimed to accurately determine DCCs for the eye lens and cornea for ocular contamination with radionuclides used in nuclear medicine., Methods: DCCs for 37 radionuclides used in nuclear medicine were determined using two different methods. Method 1 involved conducting Monte Carlo (MC) simulations of an ICRU cylinder to determine the absorbed dose at a depth of 3 mm resulting from a point source. The accuracy of this simulation approach was validated by experimental thermoluminescent dosimeter (TLD) measurements for 18 F, 68 Ga, 99m Tc, and 177 Lu. In method 2, average DCCs were calculated for the eye lens (complete and radiosensitive parts) and the cornea for both a point source and thin surface contamination centered on the cornea using MC simulations on the adult mesh-type reference computational phantom of the eye from the ICRP (MRCP)., Results: DCCs determined from TLD measurements showed excellent agreement (deviations: +1.4%, +4.7%, -3.1%, and -2.5% for 18 F, 68 Ga, 99m Tc, and 177 Lu, respectively) compared to MC simulations of the experimental set-up. For the 37 radionuclides, DCCs of the complete eye-lens for a point source ranged from 2.53 × 10 -7 to 4.15 × 10 -2 mGy MBq -1 s -1 for the adult MRCPs, being substantially smaller compared to DCCs determined via MC simulations of a ICRU cylinder. In general, point source and surface contamination showed comparable DCCs for the eye lens. Radionuclides emitting low-energy beta radiation or conversion electrons (e.g., 177 Lu, 99m Tc) showed low DCCs as the radiation does not penetrate to the depth of the eye lens, while radionuclides emitting high-energy beta radiation (e.g., 90 Y) showed high DCCs. Overall, DCCs for the radiosensitive part of the eye lens were larger (up to a factor of 3) compared to the complete eye lens. DCCs for the cornea were larger than for the eye lens with a factor that strongly depended on the emitted radiation type. Especially alpha emitters (e.g., 211 At, 223 Ra) showed high DCCs for the cornea because of the short range of alpha radiation, leading to local maxima in the cornea and not reaching the eye lens., Conclusion: DCCs at a depth of 3 mm in an ICRU cylinder and adult MRCP DCCs for both the complete and sensitive parts of the eye lens and cornea were determined for 37 radionuclides having applications in nuclear medicine. These DCCs are highly useful in radiation safety assessments and radiation dose calculations in ocular contamination incidents., (© 2024 The Authors. Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)

Background: mammography is the gold standard in the early detection of breast cancer. Due to the increase in the rate of women suffering from this malignancy all over the world, this imaging modality has been widely used. Considering the side effects caused by ionizing radiation to measure the carcinogenic risk of mammography X-rays, mean glandular dose (MGD) is the best parameter to evaluate the dose received by patients undergoing mammography. The aims of this study were to measure MGD in mammography in mammographic craniocaudal (CC) and mediolateral oblique (MLO) projections and investigate the relationship of MGD with compressed breast thickness (CBT), body mass index, age of the patient, and device exposure conditions., Materials and Methods: this cross-sectional analytical study was conducted on women aged 30-70 referring to the mammography unit of Shahid Sadoughi Hospital in Yazd city from May to August 2022. The TLD-GR 200 (thermoluminescence dosimeter) was placed on the breast of the patients for CC and MLO projections, and then the MGD was obtained by multiplying the entrance surface dose and the normalized glandular dose. Analysis of data (such as demographic information of patients, CBT, kVp, and mAs) was done by SPSS 23 software. The normality of the data was checked using Shapiro-Wilk tests. It was found that except for age, other variables did not have a normal distribution; therefore, equivalent parametric and nonparametric tests were used. In this regard, Spearman's correlation was used to assess the correlation between variables. P-value < .05 was considered as level of significance., Results: The mean ± standard deviation (SD) age of patients was 47.3 ± 7.1 years. The median ± IQR (the interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. It is defined as the difference between the 75th and 25th percentiles of the data.) (mean ± SD) value of MGD per woman was 1.2 ± 0.4 mGy (1.3 ± 0.3 mGy). The median ± IQR MGD in the MLO and CC projections was 1.6 ± 0.6 mGy and 0.9 ± 0.4 mGy, respectively. Significant relationships (P-value ≤ .001) were observed between MGD with CBT (R = 0.62) and age (R = -0.85)., Conclusion: The results showed that the mammography unit at Shahid Sadoughi Hospital in Yazd is functioning properly. The calculated median ± IQR MGD per woman referring to this unit (1.2 ± 0.4 mGy) was clearly below the dose limit recommended by American College of Radiology and International Commission on Radiological Protection (3 mGy). Moreover, among the factors affecting MGD, the highest correlation was seen between MGD and age (R = -0.85)., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

• Sentinel node biopsy using radiotracer exposes medical staff with ionizing radiation. • The yearly dose to hands of surgeon is estimated at 16 mSv/year. • Estimated skin dose to pathologist's hands is less than 1 mSv/100 patients. • The exposure of anesthesiologist and anesthetists equals to natural background of the workplace. Sentinel node biopsy is a procedure used for axillary nodal staging in breast cancer surgery. The process uses radioactive 99mTc isotope for mapping the sentinel node(s) and all the staff involved in the procedure is potentially exposed to ionizing radiation. The colloid for radiolabelling (antimone-sulphide) with 99mTc isotope (half-life 6 h) is injected into the patient breast. The injection has activity of 18.5 MBq. The surgeon removes the primary tumor and detects active lymph nodes with gamma detection unit. The tumor as well as the active nodal tissue is transferred to pathologist for the definitive findings. The aim of the study was to measure dose equivalents to extremities and whole body for all staff and suggest practice improvement in order to minimize exposure risk. The measurements of the following operational quantities were performed: Hp(10) personal dose equivalent to whole body and Hp(0.07) to extremities for staff as well as ambiental dose for operating theatre and during injection. Hp(0.07) were measured at surgeon's finger by ring thermoluminescent dosimeter (TLD) type MTS-N, and reader RADOS RE2000. Surgeon and nurse were wearing TLD personal dosimeter at the chest level. Anesthesiologist and anesthetist were wearing electronic personal dosimeters, while pathologist was wearing ring TLD while manipulating tissue samples. Electronic dosimeters used were manufactured by Polimaster, type PM1610. All TLD and electronic dosimeters data were reported, including background radiation. Background radiation was also monitored separately. Personal TLDs are standard for this type of personal monitoring, provided by accredited laboratory. Measurements of ambiental dose in workplaces of other staff involved around the patient was performed before the surgery took place, by calibrated survey meters manufactured by Atomtex, type 1667. The study involved two surgeons and one pathologist, two anesthesiologists and three anesthetists during two months period. The doses received by all staff are evaluated using passive and active personal dosimeters and ambiental dose monitors and practice was improved based on results collected. Average annual whole body dose for all staff involved in the procedure was less than 0.8 mSv. Extremity dose equivalents to surgeon and pathologist were far below the limits set for professionally exposed (surgeon) and for public (pathologist). Although has proven to be very safe for all staff, additional measures for radiation protection, in accordance to ALARA principle (As Low As Reasonably Achievable) should be conducted. The recommendations for practice improvement with respect to radiation protection were issued. [ABSTRACT FROM AUTHOR]

Background: Computed tomography (CT) is a routine procedure for diagnosing using ionization radiation which has hazardous effects especially on sensitive organs. Objective: The aim of this study was to quantify the dose reduction effect of lead apron shielding on the testicular region during routine chest CT scans. Material and Methods: In this measurement study, the routine chest CT examinations were performed for 30 male patients with common lead aprons folded and positioned in testis regions. The patient's mean body mass index (BMI) was 26.2 ± 4.6 kg/m². To calculate the doses at testis region, three thermoluminescent dosimeters (TLD-100) were attached at the top surface of the apron as an indicator of the doses without shielding, and three TLDs under the apron for doses with shielding. The TLD readouts were compared using SPSS software (Wilcoxon test) version 16. Results: The radiation dose in the testicular regions was reduced from 0.46 ± 0.04 to 0.20 ± 0.04 mGy in the presence of lead apron shielding (p < 0.001), the reduction was equal to 56%. Furthermore, the heritable risk probability was obtained at 2.0 ×10-5 % and 4.6 ×10-5 % for the patients using the lead apron shield versus without shield, respectively. Conclusion: Applying common lead aprons as shielding in the testis regions of male patients undergoing chest CT scans can reduce the radiation doses significantly. Therefore, this shield can be recommended for routine chest CT examinations. [ABSTRACT FROM AUTHOR]

Background: Thermoluminescence dosimeters are the most widely used inactive in vivo dosimeters. Nanoparticles have more suitable dosimetry properties than similar bulk materials. The purpose of this study was to synthesize and to determine the kinetic parameters of nanophosphor equivalent to human tissue for using in medical purposes. Methods: After synthesis of LiB3O5 nanophosphor, structure and its dimensions were investigated using X-ray diffraction pattern (XRD) and scanning electron microscopy (SEM). Different activators were added to each nanophosphor with 0.5, 1, and 2 percent of weight, to select the most suitable compound as a usable thermoluminescence dosimeter in medicine. The kinetic parameters of the glow peaks were calculated using four methods, and the results of these methods were compared. Findings: SEM and XRD analysis showed that the dimensions of synthesized phosphorus were less than 100 nm, and had a relatively high purity. By irradiating and reading the samples, the best peak position and intensity of the glow curve were obtained by 2 percent of weight aluminum (Al) activator at the peak temperature of 183 °C. Conclusion: The results of different methods were in good agreement. The calculated mean value of the activation energy was 1.243 eV, which had a good energy level for the thermoluminescent dosimeter (TLD) reader. By comparing the experimental and computational values, the validity of the computational methods was confirmed.

Background: Extensive use of computed tomography (CT)-scan imaging is associated with an increase in cumulative dose. Stereoradiography by electro-optical system (EOS) is an X-ray imaging technology that can reduce patient absorption dose, and increase image quality by removing scattered radiation. The aim of this study was to quantify the dose of radiation in CT-scan and stereoradiography imaging, and to compare the dose values between the two methods. Methods: This descriptive-analytical study was carried out in the Shahid Sadoughi hospital of Yazd City, Iran, with two different types of imaging apparatus, stereoradiography and CT-scan. Fifteen patients were selected randomly for each imaging method. Prior to irradiation, nine thermoluminescence dosimeters (TLDs) were installed on the target area in anterior-posterior (AP), right transverse (RT), and left transverse (LT) views. 85-110 and 120 kilovoltage peaks (kVp) were used for stereoradiography and CT-scan, respectively. The TLDs were read, and the mean dose of radiation was calculated. Finally, the statistical analysis was performed using one-way ANOVA method via SPSS software. Findings: The mean dose of radiation in stereoradiography imaging from the lower regions with AP, RT, and LT views were 0.75, 0.26, and 1.14 mGy, respectively. These values with similar views in CT-scan images were 18.08, 10.87, and 10.37 mGy, respectively. According to the results of statistical analysis, radiation dose in the all views of stereoradiography imaging was significantly lower than CT-scan. Conclusion: Using stereoradiography imaging instead of CT-scan impose a lower dose to the patient in detecting lower limb malformations, and thus reducing the risk of cancer and side effects.

Background: While the benefits of cone-beam computed tomography (CBCT) are well known in maxillofacial imaging, the use of this modality is not risk-free. Objective: The aim of this study was to evaluate the exposure doses received by patients during maxillofacial imaging with CBCT. Methods: Entrance surface dose (ESD) was measured by using thermoluminescent dosimeters (TLDs) attached to the eyes lids, parotid glands and thyroid of 64 patients in two imaging centers (A and B). Phantom dosimetry was performed by a cylindrical poly-methyl methacrylate (PMMA) head-size phantom and an ionization chamber for different exposure parameters. NewTom VGi and Planmeca Promax 3D CBCT scanners were used at centers A and B, respectively. Results: The mean ESD of the eyes, parotid glands and thyroid were 2.57, 2.33 and 0.28 mGy in center A, 0.35, 2.11 and 0.37 mGy in center B, respectively. ESD of the eyes revealed a significant difference in two centers; in center B, it was 86.4% lower than center A. In the phantom dosimetry, the measured doses of NewTom VGi were 2.63 and 2.08 mGy, respectively by changing field of view (FOV) size from 8×8 cm2 (height × diameter) to 6×6 cm2 . For Planmeca Promax 3D, it ranged from 0.98 to 3.24 mGy depending on exposure parameters. Conclusion: There is a wide range of radiation doses dependent on the units, patients and selected scan parameters. Inappropriate selection of exposure settings, especially FOV size, can seriously increase patient dose

Introduction: Quality assurance in Computed tomography (CT) centers in developing countries are largely hindered by the unavailability of CT phantoms. The development of a local CT phantom for the measurement of organ radiation absorbed dose is therefore requisite. Material and Methods: Local CT phantoms were designed to meet the standard criteria of 32 cm diameter for body, 16 cm diameter for head, and 14 cm in length respectively. The outer plastic shell was made using poly (methyl methacrylate [PMMA]) sheet. The developed CT phantoms were validated against a standard phantom. Radiation absorbed dose was determined by scanning the setup with the same protocol used for the standard phantom. The local phantoms were then verified for organ radiation absorbed dose measurement using bovine tissues. The set up was CT-scanned, and Hounsfield units (HU) for bovine tissues were obtained. Results: There was no significant difference between the local and standard head phantoms (P=0.060). Similarly, no difference was noted between the local and standard body phantoms (P=0.795). The percentage difference in volume CT dose index (CTDIvol) between the body (local and standard) phantoms was higher than that for the head phantoms. There were no significant differences in HU between bovine and human brain, liver, kidney and lung tissues (P=0.938). Conclusion: The local phantoms showed good agreement with the standard ones. The developed phantoms can be used for CT organ radiation absorbed dose measurement in radiology departments in Nigeria.

Purpose: To evaluate the use of commercial‐grade strontium aluminate phosphorescent powder as a thermoluminescent (TL) dosimeter for clinical radiotherapy beams. Materials and Method: Commercially available Eu2+, Dy3+ co‐doped strontium aluminate powder (SrAl2O4:Eu, Dy) was annealed and then irradiated using 20 × 20 cm2 field size, with 6‐MV (PDD10 = 70.7) and 18‐MV (PDD10 = 79.4) photon beams and and 9‐MeV (R50 = 3.6), 15 MeV (R50 = 5.9) and 18‐MeV (R50 = 7.2) electron beams. To calibrate the relationship between the TL readings and the irradiated doses, TL glow curves were acquired for doses up to 600 cGy at all beam energies. For the percentage depth dose (PDD) measurement, the SrAl2O4:Eu, Dy powder was sandwiched by solid water phantoms, with varying thickness of solid water placed above to determine the depth. PDDs were measured at four representative depths and compared against the commissioning depth dose data for each beam energy. Results: Linear dose response models of doses up to 200 cGy were created for all beam energies. Superlinearity was observed with doses greater than 200 cGy. The PDD measurement acquired experimentally agrees well with the commissioning data of the medical linear accelerator. Trapping parameters such as order of kinetics, activation energy and frequency factor have been obtained via TL glow curve analysis. Conclusion: The linear dose response demonstrates that SrAl2O4:Eu, Dy is a potential TLD dosimeter for both electron beams and photon beams at different beam energies. The PDD measurements further support its potential use in quality assurance and radiation dosimetry. [ABSTRACT FROM AUTHOR]

Objectives: To compare the overall diagnostic performance of digital panoramic radiographs obtained with low-dose protocols and to estimate the absorbed dose in the head and neck. Materials and methods: Forty-eight panoramic radiographs were obtained from eight imaging phantoms using six exposure protocols of progressively lower tube voltages (kVp) and currents (mA), as follows: (1) 70 kVp and 12.5 mA, (2) 66 kVp and 10 mA, (3) 66 kVp and 8 mA, (4) 66 kVp and 5 mA, (5) 66 kVp and 4 mA and (6) 66 kVp and 3.2 mA. Five oral radiologists independently evaluated the images and reported all detectable radiographic findings. Intra-examiner reproducibility was assessed by re-evaluation of 25% of the images. The data were analysed using the McNemar and weighted Kappa tests. Absorbed doses of the six protocols were obtained from thermoluminescent dosimeters placed inside a Rando phantom and compared using one-way ANOVA with post hoc Tukey (α = 0.05). Results: The overall diagnostic performance of panoramic radiographs obtained with low-dose protocols did not differ from that of panoramic radiographs obtained with the highest dose (p > 0.05). Moreover, substantial agreement was observed between all protocols. Protocol 1 resulted in the highest absorbed dose and protocols 4, 5 and 6 in the lowest absorbed doses, with the difference being significant (p ≤ 0.05). Conclusion: Although digital panoramic radiography is considered a relatively low-dose examination, the radiation dose can be further reduced without negatively affecting its overall diagnostic performance. Clinical relevance: Considering the risks associated with X-rays, digital panoramic radiographs can be obtained at even lower exposure levels. [ABSTRACT FROM AUTHOR]

Objectives: To establish conversion coefficients (CCs), between mean absorbed dose to the brain and eye lens of the cardiologist and the air kerma-area product, PKA, for a set of projections in cardiac interventional procedures. Furthermore, by taking clinical data into account, a method to estimate the doses per procedure, or annual dose, is presented., Methods: Thermoluminescence dosimeters were used together with anthropomorphic phantoms, simulating a cardiologist performing an interventional cardiac procedure, to estimate the CCs for the brain and eye lens dose for nine standard projections, and change in patient size and x-ray spectrum. Additionally, a single CC has been estimated, accounting for each projections fraction of use in the clinic and associated PKA using clinical data from the dose monitoring system in our hospital., Results: The maximum CCs for the eye lens and segment of the brain, is 5.47 μGy/Gycm2 (left eye lens) and 1.71 μGy/Gycm2 (left brain segment). The corresponding weighted CCs: are 3.39 μGy/Gycm2 and 0.89 μGy/Gycm2, respectively., Conclusions: Conversion coefficients have been established under actual scatter conditions, showing higher doses on the left side of the operator. Using modern interventional x-ray equipment, interventional cardiac procedures will not cause high radiation dose levels to the operator when a ceiling mounted shield is used, otherwise there is a risk that the threshold dose values for cataract will be reached., Advance in Knowledge: In addition to the CCs for the different projections, methods for deriving a single CC per cardiac interventional procedure and dose per year were introduced., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology.)

Zinc polycarboxylate cement is one of the few dental materials that demonstrate true adhesion to tooth structure. It is suitable for use in living organisms without causing harm. Its strong adhesion to teeth and low level of irritancy are two important parameters for the dental applications. In this study, the dosimetry properties of zinc polycarboxylate cement using thermoluminescence (TL) method were investigated and determined the effectiveness of its use as a good dosimeter. According to the results of this study, the sample shows a good TL properties with three main peaks found around 140°C, 220°C and 330°C. It has a wide linear dose response between 72 Gy and 2.3 kGy and good reusability of the TL peak found at 330°C. Unfortunately, the TL peak intensity values are rapidly faded within a short waiting time interval. Zinc polycarboxylate cement, which is frequently used in dental crowns, can be used as a retrospective dosimeter for measuring the amount of radiation in space studies and nuclear accidents due to its wide linear dose-response curve in the high dose region., (© 2024 John Wiley & Sons Ltd.)

This study investigated natural sand thermoluminescence (TL) response as a possible option for retrospective high-dose gamma dosimetry. The natural sand under investigation was collected from six locations with selection criteria for sampling sites covering the highest probability of exposure to unexpected radiation on the Egyptian coast. Dose-response, glow curve, chemical composition, linearity, and fading rate for different sand samples were studied. Energy Dispersive X-ray Spectroscopy (EDX) analysis revealed differences in chemical composition among the various geological sites, leading to variations in TL glow curve intensity. Sand samples collected from Ras Sedr, Taba, Suez, and Enshas showed similar TL patterns, although with different TL intensities. Beach sands of Matrouh and North Coastal with a high calcite content did not show a clear linear response to the TL technique, in the dose range of 10 Gy up to 30 kGy. The results show that most sand samples are suitable as a radiation dosimeter at accidental levels of exposure. It is proposed here that for high-dose gamma dosimetry with doses ranging from 3 to 10 kGy, a single calibration factor might be enough for TL measurements using sand samples. However, proper calibration might allow dose assessment for doses even up to 30 kGy. Most of the investigated sand samples had nearly stable fading rates after seven days of storage. The Ras Sedr sands sample was the most reliable for retrospective dose reconstruction., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The ultimate goal of this work is the study of the effect of luminescence stimulations and signals reading modes combinations on the thermoluminescence intensity and glow curve behaviour for the same X-ray irradiation dose. Three interesting stimulating and reading modes are considered, namely, infrared stimulated luminescence (IRSL), blue light-emitting diode stimulated luminescence (BLSL) and thermally stimulated luminescence (TSL). The studied stimulation and reading modes combination protocols are (Protocol 1) IRSL-TSL, (Protocol 2) IRSL-BLSL-TSL and (Protocol 3) BLSL-IRSL-TSL. Experiments are performed on beryllium oxide (BeO) dosimeter. Results demonstrate well that the combination of reading modes have direct impact on the TL signal in terms of intensity and glow curve shape. It was also found that when reading modes are correctly combined, particularly when IRSL is applied first, then BLSL and TL, it is possible to collect two or more exploitable signals of different stimulation types for the same irradiation that can be used for different purposes and final applications., (© 2024 John Wiley & Sons Ltd.)

Endoscopic retrograde cholangiopancreatography (ERCP) is widely used in the diagnosis and treatment of pancreatic and bile duct disorders. The procedure is performed under the guidance of fluoroscopy. This study aims to investigate the dose received by staff in the Endoscopy Department of AbuAli Sina Medicine and Organ Transplant Hospital in Shiraz. The dosimetry was performed using thermoluminescent dosemeters (TLD), type TLD-100. The values of Hp(10), Hp(3) and Hp(0.07) were estimated for the staff for 2 months. According to the results obtained in this study, the equivalent dose of the gastroenterologist's body, eye lenses and hands was 0.045 ± 0.001 mSv, 0.111 ± 0.014 mSv and 0.357 ± 0.034 $\mathrm{mSv}$, respectively. This study showed that the annual radiation exposure for ERCP department staff of Abu Ali Sinai Hospital is less than the annual dose limit. However, if the principles of proper radiation protection and individual dosimetry are followed, the dose to staff members can be reduced., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)