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Objective To design a mobile personnel radiation protection equipment for operation in environments with high radiation such as spent fuel reprocessing plants, to achieve simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol, to reduce the internal and external exposure dose of radioactive workers, and to meet the requirement of operation for two hours. Methods The core parts of the mobile personnel radiation protection equipment included a shielding chamber and a respiratory maintenance system. An automated chassis was used for the movement and lifting of the shielding chamber. MCNP software was used to simulate and calculate the protective effects of shielding chamber made of different materials and material thicknesses. Experimental verification of the shielding chamber design was conducted. Mathematical models were established to describe the variations in the content of various gases in the chamber with personnel operation time. A respiratory maintenance system, a harmful gas absorption device, and an automated mobile chassis were designed. Results The shielding chamber made of polyethylene with a thickness of 80 mm achieved an 80% neutron shielding rate. The respiratory maintenance system could support workers for 2 hours of operation inside the equipment. The mobile chassis allowed operation of the equipment with one person. Conclusion This mobile personnel radiation protection equipment can solve the problem in simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol. The equipment can provide radiation protection for radioactive workers, reduce exposure dose, and reduce personnel burden. This system provides technical means for the operation and maintenance of equipment in high-radiation sites such as spent fuel reprocessing plants.
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Objective To discuss the role of empowerment management mode in radiation protection after 125I seed implantation.Methods A total of 66 patients,who received first-time 125I seed implantation at the authors'hospital from October 2020 to October 2022,were randomly divided into control group(n=33)and study group(n=33).The patients of the control group received traditional health education,while the patients of the study group received the empowerment management mode on the basis of the traditional health education.The self-efficacy,health education effect,and protection compliance were compared between the two groups.Results The self-efficacy,health education effect,and protective compliance of patients in the study group were better than those in the control group,and the differences were statistically significant(P<0.05).Conclusion The implementation of health education by empowerment management mode can improve the effect of health education in patients after 125I seed implantation,and the patients can get better understanding about 125I seed therapy,which can strengthen their sense of self-efficacy and improve postoperative protection compliance,ensuring the safety of the surrounding crowd.The empowerment management mode is worthy of clinical promotion.(J Intervent Radiol,2024,32:82-85)
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Lung cancer is the fastest-growing cancer type in terms of incidence and mortality worldwide, posing a huge threat to the health and life of the population. Radiation therapy is one of the main methods for treating lung cancer, and there is a clear dose-effect relationship between the radiation dose and local control rate of lung cancer. However, the lung is a radiation dose-limiting organ, and the radiation resistance of lung cancer tissues and the radiation damage to normal tissues limit the radiation efficacy for lung cancer. The pathogenesis of lung cancer in traditional Chinese medicine (TCM) is characterized by an initial deficiency in vital Qi, followed by the internal invasion and gradual accumulation of pathogenic Qi. After radiation therapy for lung cancer, the body's vital Qi becomes weaker, and syndromes of phlegm coagulation, Qi stagnation, and static blood blocking collaterals become more severe, leading to radiation resistance of lung cancer tissues. Therefore, the key issue to better clinical efficacy of radiation therapy for lung cancer patients is to use drugs to enhance the radiation sensitivity of lung cancer cells and improve the radiation tolerance of normal lung tissues. TCM can be used as a radiation sensitizer by regulating the cell cycle to increase the proportion of cells in the radiation-sensitive phase, promoting upregulation of pro-apoptotic genes and downregulation of anti-apoptotic genes to induce cell apoptosis, enhancing DNA damage caused by radiation and inhibiting damage repair, improving blood circulation and tissue oxygen supply, and so on, to enhance the sensitivity of tumor cells to radiation and amplify the toxicity of radiation to tumor tissues. TCM can also be used as a radiation protector by inhibiting cell damage, regulating cytokines and immune balance, reducing the release of inflammatory and fibrotic factors, and inhibiting the activation of related signaling pathways to prevent and treat radiation-induced lung injury. This article systematically reviewed the research results of TCM on radiation sensitization and radiation protection in lung cancer in recent years, aiming to elucidate the mechanism of TCM in regulating the effect of radiation therapy for lung cancer and provide more theoretical and practical basis for TCM to participate in improving the prognosis of lung cancer patients undergoing radiation therapy.
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Objective To investigate the current status of radiation protection in non-medical radiation workplaces in Yantai, China, and to provide a scientific basis for occupational health management in non-medical radiation workplaces. Methods Non-medical radiation workplaces in Yantai were investigated using a questionnaire survey in 2022, including radiation source term, occupational health examination, personal dose monitoring, personal protective equipment, and radiation protection testing workplaces. Data were entered by a double-entry method and then analyzed. Results There were 56 non-medical radiation workplaces in Yantai, covering manufacturing, nonferrous metal ore mining, nuclear power plant, transportation, and technical services. There were 0 Class I radiation device, 150 Class II radiation devices, and 10 Class III radiation devices; there were 80 Class I radiation sources, 16 Class II radiation sources, 14 Class III radiation sources, 62 Class IV radiation sources, and 135 Class V radiation sources. There were 998 radiation workers, with an occupational health examination rate and personal dose monitoring rate of 98.3%. Among the 56 non-medical radiation workplaces, 47 (83.9%) were equipped with radiation protection monitoring instruments, 24 (51.1%) workplaces had verified the radiation protection monitoring instruments, with 2017 personal dose monitoring instruments and 2327 personal protective equipment in place, 42 (75%) workplaces carried out occupational health assessments, 44 (78.6%) workplaces carried out self-detection, and 53 (94.6%) workplaces carried out entrusting detections (monitoring pass rate: 100% [53/53]). The declaration rate of occupational hazard items was 87.5% (49/56). Conclusion There is still a gap between the current status and the requirements in the national regulations and standards regarding radiation protection in non-medical radiation workplaces. Therefore, the supervision and management of non-medical radiation workplaces should be further strengthened, especially the configuration and verification of radiation protection monitoring instruments.
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Objective To investigate the number, distribution, and types of radiation of non-medical radiation institutions in Hebei Province, China, and to explore the current radiation protection in the employing units and occupational health management of radiation workers in 2022. Methods A questionnaire survey was conducted in the non-medical institutions engaged in nuclear technology application in Hebei Province, and different types of employing units were selected to monitor the radioactivity level in the workplace. Results A total of 681 non-medical institutions engaged in radiation technology application completed the survey, covering all cities with subordinate districts in the province, including 1605 radioactive devices, 2960 active devices, 45 non-uranium metal mines, and 14 non-sealed workplaces. A total of 8617 radiation workers were surveyed, with a personal dose monitoring rate of 70.9%, a radiation protection training rate of 61.1%, and an occupational health examination rate for radiation workers of 59.3%. A total of 614 radiation protection monitoring instruments were provided, with a personal protective equipment allocation rate of 51.1% and a personal dose alarm device allocation rate of 51.8%. The radiation occupational hazardous factor testing was completed for 54 workplaces, and the results were all qualified. Conclusion There are still significant deficiencies in personal dose monitoring in the radiation work units in non-medical institutions and occupational health examination in the radiation work units in our province. The health administrative departments should strengthen health supervision and law enforcement, enhance radiation protection and skill training for employers, and more effectively control the impact of radiation hazards on personnel health.
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Objective To understand the basic information of the number, classification, and distribution of radiation work units in non-medical institutions in Shanxi Province, China, and to analyze the status quo of health management and radiation protection measures for radiation workers, so as to provide a scientific basis for occupational exposure protection in non-medical radiation work units and better protect the occupational health rights and interests of radiation workers. Methods A questionnaire survey was conducted to investigate some non-medical institutions in Shanxi Province. On-site testing was carried out to determine the risk factors for radioactive occupational diseases in the selected non-medical institutions. Results In 220 non-medical institutions, there were 340 radiation devices and 2284 radioactive sources. The rate of individual dose monitoring was 92.7% and the rate of occupational health examination was 87.2%. These devices were equipped with 325 detection instruments for radiation protection, 1316 personal protective equipment, and 730 personal dose alarms. Radiation occupational disease risk factors were investigated in 101 institutions. Conclusion The occupational health management of radiation workers in non-medical institutions in Shanxi Province is generally in line with the national standards. However, there is still a big gap with the level of occupational health management in medical institutions. The health administration departments should clarify the management measures for non-medical institutions and strengthen their supervision and management functions.
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Radiation-induced injury, a body dysfunction caused by irradiation, is associated with the dose, duration, and speed of radiation and is predominantly derived from radiation therapy for patients with malignant tumors. The current clinical treatment mainly includes amelioration of injury, alleviation of symptoms, and improvements in function restoration of the affected sites because of lack of targeted agents specific to radiation-induced injuries. Research and development of preventive and therapeutic agents against radiation-induced injuries are of great significance to reduce the body damages caused by radiotherapy and improve the quality of life of cancer survivors. This review summarizes the radiation-induced injury and its mechanisms, radioprotectants, and therapeutic agents for radiation, and proposes future development directions, so as to provide a reference for alleviation of radiation-induced injury and improvement in prognosis.
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Objective:To explore the radiological protection measures for yttrium-90 ( 90Y)-loaded resin microsphere therapy in clinical application. Methods:The surgical operation process for 90Y-loaded resin microsphere therapy was simulated, involving measurement of ambient dose equivalent rates at various stages: preoperative preparation (dominated by drug package), drug transfer, intraoperative procedures (drug operation and injection), and postoperative care and observation within the hospital. Based on the simulation, the protection measures in clinical application were analyzed. Results:The dose equivalent rate ranged from 0.12 to 0.42 μSv/h around the active chamber and from 1.04 to 3.32 μSv/h in the fume hood. Around the digital subtraction angiography (DSA) room, the maximum dose equivalent rate was 0.78 μSv/h when 90Y and DSA were applied simultaneously and 0.36 μSv/h when 99Tc m and DSA were applied. For the first operating position in the fluoroscopy protection area, the maximum dose equivalent rate was 13.19 μSv/h at 155 cm height when only 90Y was applied, and 315.01 μSv/h at 80 cm height when 90Y and DSA were applied. For the second operating position, the maximum dose equivalent rate was 6.28 μSv/h at 155 cm height when only 90Y was applied and 291.03 μSv/h at the same height when 90Y and DSA were applied. The dose-equivalent rates ranged from 0.11 to 0.58 μSv/h around the dedicated ward for postoperative patients. Conclusions:The existing shielding measures, such as those in the nuclear medicine department and interventional room, meet the radiation protection requirements for 90Y-loaded resin microsphere therapy. However, it is still necessary to conduct a scientific assessment based on the actual situation. Additionally, radiation protection measures and surface contamination treatment should be enhanced during drug operation.
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In recent years, digital radiography (DR) system is widely used in China, and digital X-ray radiography is one of the most common examinations for bone and joint. Optimizing the osteoarthrographic technique, standardizing osteoarthrogram, and summarizing the requirements for radiation protection, will further enhance the clinical application value of digital X-ray imaging in bone and joint examination. Referring to domestic and foreign literatures, and combining the clinical situation of Guangdong-Hong Kong-Macao Greater Bay Area, the experts recruited by the Guangdong-Hong Kong-Macao Greater Bay Area Imaging Technology Alliance reach a consensus on the technique and protection specifications for bone and joint examination to guide and standardize the work related to X-ray examination of bone and joint in the medical imaging department of medical institutions at all levels in the Greater Bay Area.
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Radiation therapy (RT) is a well-established and widely used treatment modality for prostate cancer. As prostate-rectum proximity contributes to rectal toxicity, there is growing interest in rectal protection. Technical advances have enabled the reduction of rectal injury. To improve the safety of prostate cancer radiotherapy and minimize the rectal toxicity of irradiation, the advances in rectal protection technique during prostate cancer radiotherapy, including technical advances of radiation therapy, image-guided radiotherapy, application of endorectal balloons, and use of rectum spacers, were reviewed, aiming to provide reference for improving the safety of prostate cancer radiotherapy and alleviating rectal radiation injury.
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Objective To analyze the impact of different maze structures of medical electron linear accelerator on the radiation level at the entrance of the treatment room. Methods The Monte Carlo simulation method was used to compare the radiation field distribution in two accelerator rooms with different maze widths and to conduct a detailed analysis of the radiation levels. Results The radiation level at the entrance of the accelerator room with a wide maze was significantly higher than that at the entrance of a compact maze. The neutron radiation level at the entrance of the narrow maze model decreased by 38.6% compared to the wide maze model, and the level of X-ray radiation also showed a declining trend. Conclusion When designing medical electron linear accelerators, a compact maze structure should be adopted to reduce the setting of unnecessary space, thereby lowering the radiation level at the entrance of the treatment room and enhancing the effectiveness of radiation protection.
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Introducción: Las radiografías dentales son una de las exposiciones médicas más frecuentes a la radiación ionizante. El uso de radiación ionizante está asociado a un riesgo probable de desencadenar efectos biológicos adversos y posibles daños a la salud del paciente. Para evitar que los pacientes reciban dosis innecesariamente altas durante estas exposiciones, la Comisión Internacional de Protección Radiológica recomienda la utilización de los niveles de referencia para diagnóstico, como una herramienta efectiva de ayuda a la optimización de la protección radiológica de los pacientes. Objetivo: Estimar los niveles de referencia para diagnóstico en radiografía dental intraoral y panorámica en la ciudad de Bogotá, D. C. Metodología: Se evaluaron los parámetros de exposición radiográficos de los equipos y la calidad de imagen en 68 equipos de radiografía dental periapical y 23 equipos de radiografía panorámica. Se estimaron las magnitudes dosimétricas de kerma incidente en aire (Kai) en equipos intraorales para la radiografía de un maxilar molar de un adulto y el producto kerma aire-área (PKA) en equipos de radiografía panorámica en un examen de un adulto estándar. Resultados: El tercer cuartil de la distribución de kerma incidente en aire para radiografía intraoral fue de 3,3 mGy y del producto kerma aire-área para radiografía panorámica fue de 103,9 mGycm2. En la distribución de frecuencias de kerma incidente en aire para radiografía intraoral, el porcentaje más alto de equipos estuvo en el rango de 2,0-3,0 mGy. En la distribución de frecuencias del producto kerma aire-área para los equipos de radiografía panorámica, el porcentaje más alto de equipos estuvo en el rango de 60 a 80 mGycm2. Discusión: Las instituciones consideradas para establecer los Niveles de Referencia para Diagnóstico en este estudio contaron con una adecuada calidad de la imagen evaluada con un maniquí dental, pero las variaciones en las dosis de radiación entre instituciones señalan la necesidad de implementar herramientas que contribuyan a la optimización de las prácticas. Conclusiones: Se recomienda usar los valores de los niveles de referencia para diagnóstico encontrados en esta investigación para optimizar la protección radiológica en las exposiciones radiológicas dentales, y se espera que este estudio sirva de base para nuevas investigaciones en las demás ciudades del país.
Introduction: Dental X-rays are one of the most frequent medical exposures to ionizing radiation. The use of ionizing radiation is associated with a probable risk of triggering adverse biological effects and possible damage to the patient's health. To prevent patients from receiving unnecessarily high doses during these exposures, the International Commission on Radiological Protection recommends the use of diagnostic reference levels as an effective tool to help optimize radiological protection for patients. Objective: To estimate diagnostic reference levels in intraoral and panoramic dental radiography in the city of Bogotá, D.C. Methodology: In 68 periapical dental radiography equipment and 23 panoramic radiography equipment, the radiographic exposure parameters of the equipment and image quality were evaluated. The dosimetric magnitudes of incident air kerma (Ka,i) in intraoral equipment for the radiography of a maxillary molar of an adult and the air kerma-area product (PKA) in panoramic radiography equipment in a standard adult examination were estimated. Results: The third quartile of the incident air kerma distribution for intraoral radiography was 3,3 mGy and the air kerma-area product for panoramic radiography was 103,9 mGycm2. In the frequency distribution of incident air kerma for intraoral radiography, the highest percentage of equipment was in the range of 2,0-3,0 mGy, and in the frequency distribution of the air kerma-area product for equipment of panoramic radiography, the highest percentage of the equipment was in the range of 60 to 80 mGy cm2. Discussion: The institutions considered to establish the diagnostic reference levels in this study had an adequate quality of the image evaluated with a dental phantom, but the variations in radiation doses between institutions indicate the need to implement tools that contribute to the optimization of the practices. Conclusions: It is recommended to use the values of the diagnostic reference levels found in this research to optimize radiological protection in dental radiological exposures, and it is expected that this study will serve as a basis for further research in other cities of the country.
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La endoscopía digestiva ha evolucionado de una técnica puramente diagnóstica a un procedimiento terapéutico. Esto es posible en muchos casos gracias al uso de fluoroscopía, lo cual conlleva la exposición a radiaciones ionizantes tanto de los pacientes como del personal actuante. La colangiopancreatografía retrógrada endoscópica (CPRE), que requiere necesariamente de fluoroscopia, es catalogada por la Food and Drug Administration como un examen con potencial riesgo de desencadenar lesiones inducidas por radiación. El presente artículo de revisión repasa los efectos biológicos de las radiaciones, los tipos de equipos radiológicos utilizados en CPRE, así como las magnitudes y unidades dosimétricas, para finalmente abordar los elementos de radio protección en la sala de endoscopia. El objetivo es brindar al lector la informacion para poder realizar estos procedimientos con la mayor seguridad radiológica tanto para los pacientes como para el personal ocupacionalmente expuesto.
Endoscopy has evolved from a purely diagnostic technique to a therapeutic procedure. This is possible in many cases thanks to the use of fluoroscopy, which entails exposure to ionizing radiation for both patients and the personnel involved. Endoscopic retrograde cholangiopancreatography (ERCP), which necessarily requires fluoroscopy, is classified by the Food and Drug Administration as an examination with a potential risk of triggering radiation induced injuries. This article reviews the biological effects of radiation, the types of radiological equipment used in ERCP, as well as the magnitudes and dosimetric units, to finally address the radio protection elements in the endoscopy room. The objective is to provide the reader with the information to be able to perform these procedures with the greatest radiological safety for both patients and occupationally exposed personnel.
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Introducción: el diseño de los búnkeres de radioterapia es de vital importancia no solo por la seguridad radiológica, sino también por el costo que implican. Los cálculos de blindaje de las paredes primarias de los búnkeres de los aceleradores lineales de radioterapia se determinan a partir del factor de uso de estas paredes. Los documentos internacionales como el NCRP 151 utilizan para el cálculo de estas barreras un factor de uso igual a 0.25. Objetivo: estudiar la distribución del uso de las barreras primarias en función de los tratamientos realizados buscando contrastar la homogeneidad en el uso de las barreras. Material y Métodos: con los datos de pacientes realizados durante un año (2021) en dos aceleradores lineales, uno dual y otro monoenergético, se generó una base de datos con la que se calculó la frecuencia de uso de las paredes primarias. En el presente trabajo se evalúa la diferencia entre el uso dado de las barreras y las estimaciones de uso internacional. Resultados: se encuentra que en el acelerador dual en la energía de 15X los campos más usados tienen ángulos de gantry 0º, 90º, 180º, 270º, teniendo un peso acumulado aproximado al 65% al igual que la carga de trabajo para esos ángulos, esto implica que los ángulos diferentes a estos tienen un uso muy inferior al previsto por el cálculo inicial. En el acelerador dual en la energía de 6X el campo más usado es a 0º teniendo un peso aproximado al 14%, pero la carga de trabajo a 0º no se diferencia apreciablemente del resto de los ángulos ya que la distribución no tiene direcciones preferenciales, ninguno de los valores llega a 10% que concuerda con el uso homogéneo de la barrera. En el acelerador monoenergético el peso relativo de los ángulos de 90º y 270º en el uso de las barreras es aproximadamente 34% para cada una, superior al 25% estimado inicialmente. Conclusiones: las barreras primarias de los búnkeres de radioterapia tienen espesores marcados por el cálculo de blindaje, los cuales se pueden hacer basados en documentos internacionales que son referencia del tema. Se considera en las referencias para la barrera primaria un factor de uso igual para las mismas, sin embargo en la práctica clínica se pueden tener un factor de uso no uniforme respondiendo a los tipos de tratamientos que se designen realizar en el equipo. Esta realidad abre la puerta para plantear blindajes optimizados que podrían generar búnkeres más económicos y mejor utilización del espacio de acuerdo a las condiciones dadas para cada caso en particular.
Introduction: The design of radiotherapy bunkers is of vital importance not only for radiation safety, but also for the cost involved. The shielding calculations of the primary walls of radiotherapy linear accelerator bunkers are determined from the use factor of these walls. International documents such as NCRP 151 use for the calculation of these barriers a usage factor equal to 0.25. Objective: to study the distribution of the use of primary barriers according to the treatments performed, seeking to contrast the homogeneity in the use of the barriers. Material and Methods: with the data of patients performed during one year (2021) in two linear accelerators, one dual and the other monoenergetic, a database was generated with which the frequency of use of the primary walls was calculated. The present work evaluates the difference between the given use of the barriers and the estimates of international use. Results: it is found that in the dual accelerator at 15X energy the most used fields have gantry angles 0º, 90º, 180º, 270º, having an accumulated weight of approximately 65% as well as the workload for those angles, this implies that the angles different from these have a use much lower than the one foreseen by the initial calculation. In the dual accelerator at 6X energy the most used field is at 0º having an approximate weight of 14%, but the workload at 0º is not appreciably different from the rest of the angles since the distribution does not have preferential directions, none of the values reaches 10% which is consistent with the homogeneous use of the barrier. In the monoenergetic accelerator, the relative weight of the 90º and 270º angles in the use of the barriers is approximately 34% for each one, higher than the 25% initially estimated. Conclusions: the primary barriers of radiotherapy bunkers have thicknesses marked by the shielding calculation, which can be made based on international documents that are a reference on the subject. It is considered in the references for the primary barrier an equal use factor for them, however in clinical practice they can have a non-uniform use factor responding to the types of treatments that are designed to be performed in the equipment. This reality opens the door to propose optimized shielding that could generate more economical bunkers and better use of space according to the conditions given for each particular case.
Introdução: O projeto de bunkers de radioterapia é de vital importância não apenas para a segurança da radiação, mas também para o custo envolvido. Os cálculos de blindagem para as paredes primárias dos bunkers de aceleradores lineares de radioterapia são determinados com base no fator de uso dessas paredes. Documentos internacionais, como o NCRP 151, usam um fator de uso igual a 0,25 para o cálculo dessas barreiras. Objetivo: estudar a distribuição do uso de barreiras primárias de acordo com os tratamentos realizados, buscando contrastar a homogeneidade no uso das barreiras. Material e métodos: com os dados de pacientes tratados durante um ano (2021) em dois aceleradores lineares, um dual e outro monoenergético, foi gerado um banco de dados com o qual foi calculada a frequência de uso das paredes primárias. Este artigo avalia a diferença entre o uso determinado de barreiras e as estimativas internacionais de uso. Resultados: verifica-se que no acelerador duplo com energia de 15X os campos mais utilizados são os ângulos de pórtico 0º, 90º, 180º, 270º, com um peso acumulado de aproximadamente 65%, assim como a carga de trabalho para esses ângulos, o que implica que os ângulos diferentes desses têm um uso muito menor do que o previsto pelo cálculo inicial. No acelerador duplo a 6X de energia, o campo mais utilizado é o de 0º com um peso aproximado de 14%, mas a carga de trabalho em 0º não é sensivelmente diferente do resto dos ângulos, já que a distribuição não tem direções preferenciais, nenhum dos valores chega a 10%, o que é consistente com o uso homogêneo da barreira. No acelerador de monoenergia, o peso relativo dos ângulos de 90º e 270º no uso das barreiras é de aproximadamente 34% para cada um, superior aos 25% estimados inicialmente. Conclusões: as barreiras primárias dos bunkers de radioterapia têm espessuras balizadas pelo cálculo de blindagem, que pode ser feito com base em documentos internacionais que são referência no assunto. As referências para a barreira primária consideram um fator de uso igual para elas, mas na prática clínica elas podem ter um fator de uso não uniforme, dependendo do tipo de tratamento que o equipamento foi projetado para realizar. Essa realidade abre as portas para uma blindagem otimizada que poderia gerar bunkers mais econômicos e melhor uso do espaço de acordo com as condições dadas para cada caso específico.
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Radiation Protection , Radiotherapy , Shielding against Radiation , Radiation MeasurementABSTRACT
Abstract Objective: To measure the potential radiation dose emitted by patients who have recently undergone diagnostic nuclear medicine procedures, in order to establish optimal radiation safety measures for such procedures. Materials and Methods: We evaluated the radiation doses emitted by 175 adult patients in whom technetium-99m, iodine-131, and fluorine-18 radionuclides were administered for bone, kidney, heart, brain, and whole-body scans, as measured with a radiation detector. Those values served as the basis for evaluating whole-body radiopharmaceutical clearance, as well as the risk for the exposure of others to radiation, depending on the time elapsed since administration of the radiopharmaceutical. Results: The mean time to clearance of the radiopharmaceuticals administered, expressed as the effective half-life, ranged from 1.18 ± 0.30 h to 11.41 ± 0.02 h, and the mean maximum cumulative radiation dose at 1.0 m from the patients was 149.74 ± 56.72 µSv. Even at a distance of 0.5 m, the cumulative dose was found to be only half and one tenth of the limits established for exposure of the general public and family members/caregivers (1.0 mSv and 5.0 mSv per episode, respectively). Conclusion: Cumulative radiation doses emitted by patients immediately after diagnostic nuclear medicine procedures are considerably lower than the limits established by the International Commission on Radiological Protection and the International Atomic Energy Agency, and precautionary measures to avoid radiation exposure are therefore not required after such procedures.
Resumo Objetivo: O objetivo deste trabalho foi levantar o potencial de dose de radiação emitida por pacientes em procedimentos diagnósticos, visando a estabelecer cuidados de radioproteção mais otimizados. Materiais e Métodos: Taxas de dose de radiação emitidas por 175 pacientes administrados com os radionuclídeos 99mTc, 131I e 18F para cintilografias óssea, renal, cardíaca, cerebral e corpo inteiro, foram mensuradas com um detector de radiação, servindo para avaliar o clareamento do radiofármaco no organismo e risco de exposição após administração dos radiofármacos. Resultados: O clareamento, representado pela meia-vida efetiva, variou de 1,18 ± 0,30 h até 11,41 ± 0,02 h e a dose de radiação máxima acumulada oferecida pelos pacientes a 1,0 m foi de 149,74 ± 56,72 µSv. Mesmo para distâncias de 0,5 m, as doses estimadas foram, respectivamente, duas e dez vezes inferiores ao nível de restrição para o público geral (1,0 mSv) e exposição médica (5,0 mSv/episódio). Conclusão: Doses de radiação oferecidas por pacientes em procedimentos diagnósticos são inferiores aos níveis de restrição recomendados pela International Commission on Radiological Protection e International Atomic Energy Agency, e assim, cuidados de radioproteção são geralmente desnecessários.
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Objective To determine the responses of radioactivity meter at different positions in the vertical direction of the ionization chamber by measuring different radioactive sources. Methods The radiation of cesium-137, cobalt-60, and americium-241 nuclides was measured at different positions in the vertical direction of the ionization chamber with commonly used clinical radioactivity meters. The measured values were fitted to obtain three trend lines. The maximum deviation of the measured values was estimated according to the trend line, and the deviation was estimated at different syringe needle heights. Results According to the trend lines, the maximum deviation of the radioactivity meter CRC-55tR in measuring cesium-137, cobalt-60, and americium-241 nuclides was 5.15%, 5.98%, and 6.25% respectively. The radioactivity meter RM-905a was used to measure three nuclides at different syringe needle heights, and the maximum deviations were −4.33%, −9.9%, and −12.65%, respectively. Conclusion The three nuclides showed different change patterns in measurement with CRC-55tR and RM-905a but similar change patterns in measurement with the same radioactivity meter. The values measured with the same radioactivity meter showed significant deviations at different positions in the vertical direction of the ionization chamber. It is recommended to make position correction for commonly used nuclides. Reducing measurement error and improving measurement accuracy of nuclides are of great significance for radiation protection.
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Objective To evaluate the radiation protection of “four-in-one” dental X-ray equipment and to investigate the safety interlock of the equipment by measuring the scattered radiation at the position of the patient during operation. Methods A cone-beam CT dental phantom was used to simulate the patient’s head. The intra-oral and extra-oral components of the “four-in-one” X-ray equipment were installed in a 5 m2 room. The scattered radiation at patient position was measured using a γ/X-ray survey meter, and the effects of intra-oral and extra-oral components were compared. Results For a 5 m2 room, when CBCT was exposed under typical conditions, the dose at the patient's position was 10.70 uSv/h when there was an intra-oral component and 10.60 uSv/h when there was no intraoral component. The intra-oral part did not affect the radiation dose at the patient's position. When the intra-oral component was exposed, the dose rate at the patient's position was 4.05-6.85 uSv/h, and the extra-oral part did not affect the scattered dose of the patient examined with intra-oral components. Conclusion The evaluation of radiation protection of new equipment must comprehensively consider radiation safety and equipment operation safety. The results of this study provide suggestions for clinical radiation protection supervision and evaluation of “four-in-one” dental X-ray equipment.
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Objective To investigate the awareness of and attitudes towards radiation safety and protective measures among clinical nurses in liver interventional department, so as to provide insights into the formulation of radiation-protective measures among clinical healthcare workers. Methods A cross-sectional study was performed. Clinical nurses in liver interventional departments of class A tertiary hospitals in Jiangsu Province were sampled, and the awareness of and attitudes towards radiation safety and protective measures were investigated using self-designed questionnaires. Results A total of 112 questionnaires were allocated, and 97 valid questionnaires were recovered, with an effective recovery rate of 86.61%. The awareness of questions including “interventional therapy may cause radiation exposure” and “wearing lead apron may reduce radiation exposure” was both 100.00% among respondents, and the awareness of questions including “radiation exposure may cause congenital malformations in babies”, “radiation exposure may cause cancers such as skin cancer and leukemia”, “radiation exposure may cause death”, “wearing lead goggles may reduce radiation exposure”, and “wearing thyroid shields may reduce radiation exposure” was all higher than 95.00%, while the awareness of questions “radiation exposure may cause cataract of the eye lens” and “radiation exposure may cause bone marrow depression” was relatively low. Respondents presented high-level attitudes towards lead aprons, and low-level attitudes towards goggles and thyroid shields. Conclusion The awareness of radiation safety knowledge is high among clinical nurses in liver interventional departments; however, an overall low-level attitude is seen towards radiation-protective measures. Health education pertaining to radiation safety and protective measures is required to be improved, so as to increase the compliance to radiation-protective measures.
ABSTRACT
With the rapid development of nuclear medicine, the number of nuclear medical staff has increased a lot in the past few years in China. Close-range operations, such as preparation and injections of radiopharmaceuticals, are usually carried out in nuclear medicine department. And the use of unsealed radionuclides may also create internal exposure risk. So, occupational exposure of nuclear medical staff is a main issue of occupational health management in China. In this paper, the occupational exposure level and requirements for radiation protection of nuclear medical staff are introduced to provide references for the related work that radiological health technical institutions carry out.
Subject(s)
Humans , Radiation Protection , China , Medical Staff , Occupational Exposure/prevention & control , Occupational HealthABSTRACT
Radiation protection drugs are often accompanied by toxicity, even amifostine, which has been the dominant radio-protecting drug for nearly 30 years. Furthermore, there is no therapeutic drug for radiation-induced intestinal injury (RIII). This paper intends to find a safe and effective radio-protecting ingredient from natural sources. The radio-protecting effect of Ecliptae Herba (EHE) was discovered preliminarily by antioxidant experiments and the mouse survival rate after 137Cs irradiation. EHE components and blood substances in vivo were identified through UPLC‒Q-TOF. The correlation network of "natural components in EHE-constituents migrating to blood-targets-pathways" was established to predict the active components and pathways. The binding force between potential active components and targets was studied by molecular docking, and the mechanism was further analyzed by Western blotting, cellular thermal shift assay (CETSA), and ChIP. Additionally, the expression levels of Lgr5, Axin2, Ki67, lysozyme, caspase-3, caspase-8,8-OHdG, and p53 in the small intestine of mice were detected. It was found for the first time that EHE is active in radiation protection and that luteolin is the material basis of this protection. Luteolin is a promising candidate for RⅢ. Luteolin can inhibit the p53 signaling pathway and regulate the BAX/BCL2 ratio in the process of apoptosis. Luteolin could also regulate the expression of multitarget proteins related to the same cell cycle.