Objective To systematically analyze the medical radiation exposure levels in a district of Ningbo City and to provide a scientific basis for the reasonable and effective control of medical radiation exposure. Methods Based on the radiological diagnosis frequency and dose information system, basic medical radiation exposure data were collected, such as radiation doses received by patients in various X-ray diagnostic examinations, from all 13 public medical institutions in a district of Ningbo City from January 1 to December 31, 2020. The data were analyzed for the percentage and collective effective dose of various diagnostic examinations, the distribution of examinations by sex and age, and the number of patients undergoing two or more examinations and their cumulative doses within multiple time intervals. Results Among medical X-ray diagnostic examinations in the district, the percentages of CT examination and routine photography examination were 50.88% and 47.93%, respectively, and the collective effective dose of CT examination accounted for 97.75%. By age and sex, the frequency of examination was the highest in the age group of 45-54 years, and the frequency of examination in the male was higher than that in the female before age 55. The annual effective dose for two patients exceeded 100 mSv. Conclusion In this study, CT examination accounted for up to 50.88% of all medical X-ray diagnostic examinations, and contributed 97.75% of the collective effective dose, highlighting the need for particular attention to the justification of medical radiation exposure from CT.

Objective:To analyze the eye lens dose and annual effective dose to interventional radiation workers in some hospitals of Xinxiang city from 2020 to 2022, and to ascertain the dose to interventional radiation workers.Methods:By using TLDs, the eye lens dose Hp(3) and annual effective dose Hp(10) were monitored for three consecutive years in six hospitals in Xinxiang city. The lens doses and annual effective doses to intervention radiation workers in different years in different-level hospitals and departments were analyzed. Results:From 2020 to 2022, a total of 117 people were monitored. The left eye lens dose range was 0.12-164.24 mSv, and the right eye lens dose range was 0.07-51.64 mSv. The average annual dose was 8.56 mSv for left eye lens and 4.49 mSv for right eye lens The average annual dose distribution in the MDL-5 mSv range for the left and right eye lens was 60.68% and 73.50%, respectively. 9.41% (11 people) of the left eye lens doses exceeded 20 mSv. The annual effective doses range was 0.11-31.27 mSv, with average annual dose of 2.56 mSv. The proportion of average annual effective doses mainly distributed in the range of MDL to 1.25 mSv was 52.14%, with 2.56% annual effective dose exceeding 20 mSv. There was no significant difference in left and right eye lens dose and annual effective dose between the tertiary hospitals and the secondary hospitals in three years ( P>0.05). Compared with different departments, the cumulative per capita dose in three years was statistically significant (left eye H=11.42, right eye H=13.72, annual effective dose H=25.94, P<0.05). The lens dose and annual effective dose in neurology department were lower than those in cardiology department and comprehensive intervention department ( Zcardiology department=-3.33, -3.78, -4.83, P<0.05; Zcomprehensive intervention department=-2.71, -2.63, -4.39, P<0.05). Conclusions:Most of the annual equivalent dose and annual effective dose to eye lens of the interventional radiation workers in Xinxiang city meet the national limits, but some of them have higher doses and exceed the national limits. It is suggested that the routine and continuous monitoring of eye lens doses to interventional radiologists should be strengthened while routine monitoring of annual effective dose, and attention should be paid to the eye lens and annual effective dose to interventional radiologists in secondary hospitals to improve the awareness of protection.

Objective To evaluate the application of three deep learning algorithms in automatic segmentation of clinical target volumes (CTVs) in high-dose-rate brachytherapy after surgery for endometrial carcinoma. Methods A dataset comprising computed tomography scans from 306 post-surgery patients with endometrial carcinoma was divided into three subsets: 246 cases for training, 30 cases for validation, and 30 cases for testing. Three deep convolutional neural network models, 3D U-Net, 3D Res U-Net, and V-Net, were compared for CTV segmentation. Several commonly used quantitative metrics were employed, i.e., Dice similarity coefficient, Hausdorff distance, 95th percentile of Hausdorff distance, and Intersection over Union. Results During the testing phase, CTV segmentation with 3D U-Net, 3D Res U-Net, and V-Net showed a mean Dice similarity coefficient of 0.90 ± 0.07, 0.95 ± 0.06, and 0.95 ± 0.06, a mean Hausdorff distance of 2.51 ± 1.70, 0.96 ± 1.01, and 0.98 ± 0.95 mm, a mean 95th percentile of Hausdorff distance of 1.33 ± 1.02, 0.65 ± 0.91, and 0.40 ± 0.72 mm, and a mean Intersection over Union of 0.85 ± 0.11, 0.91 ± 0.09, and 0.92 ± 0.09, respectively. Segmentation based on V-Net was similarly to that performed by experienced radiation oncologists. The CTV segmentation time was < 3.2 s, which could save the work time of clinicians. Conclusion V-Net is better than other models in CTV segmentation as indicated by quantitative metrics and clinician assessment. Additionally, the method is highly consistent with the ground truth, reducing inter-doctor variability and treatment time.

Objective To study the unqualified items in the reported quality control tests of linear accelerators, analyze the issues in quality control tests, and propose the key points and development directions for accelerator quality control test in China. Methods A literature review was conducted using the CNKI database to analyze the qualified rates of test items and the issues in quality control tests. Results In the literature on the quality control tests of linear accelerators, except for a few provinces where the qualified rates of all test items were 100%, unqualified items were reported in most of the literature. There were unqualified items related to X-ray and electron beam in different reports. Error of dose indication was the unqualified item with the highest occurrence rate in X-ray test, and the item with the lowest qualified rates in X-ray and electron beam tests. The lowest qualified rate of X-ray dose indication error was 73.5% in 2016, and the lowest qualified rate of electron beam dose indication error was 46.2% in 2017. Conclusion Tests should be carried out strictly according to the items and intervals specified by the quality control test standards. Hospitals, radiation health technology service institutions, and health administrative departments should each fulfill their respective responsibilities, work together, and place emphasis on ensuring effective quality control tests of linear accelerators to further enhance the overall quality control standards for these devices.

Objective:To estimate and analyze the levels of occupational exposure of aircrews in China, and to provide scientific basis for strengthening occupational health management.Methods:Through the FlightAware website, the flight data were collected of a total of 104 routes flying between airports with large passenger volume in China. Four kinds of cosmic radiation dose estimation programs CARI, SIEVERT, PCAIRE, and JISCARD-EX were compared and analyzed from the aspects of covering the number of airports in China, program user experience and example calculation of airline effective dose. Based on route logs, CARI-7A was applied to estimate the levels of occupational exposure of Chinese aircrews to cosmic radiation.Results:The difference in the effective doses calculated by use of these four cosmic radiation dose estimation programs for the routes with different solar activity levels was statistically significant ( M=7.52-180.98, P<0.05). The annual effective dose estimated by PCAIRE for 68 routes from 2014 to 2021 was significantly higher than that estimated by CARI-7A ( Z=2.52, P<0.05). Based on CARI-7A, the annual effective doses from cosmic radiation to aircrews in China from 2014 to 2021 were estimated, being 1.26 (0.57-2.35) mSv for flight attendants and 1.03 (0.47-1.92) mSv for pilots. The effective dose from cosmic radiation to aircrews on a single flight on some high-frequency routes in China ranged from 0.57 to 6.88 μSv. Conclusions:The level of occupational exposure of Chinese aircrews to cosmic radiation meets the requirements of national standards, but is higher than that of occupational exposure from medical and industrial applications of radiation, so it is still necessary to further strengthen the mamagememt of occupational exposure and occupational health of aircrews.

With the awareness of the hazards of ionizing radiation to human health and the consequent research on the biological effects and protective measures against ionizing radiation, the radiological health has gradually developed. Therefore, as one of the five major areas of health under the traditional public health system, the study on radiological health mainly involves the harmful effects of ionizing radiation on human health and its comprehensive protection measures. After nearly a century of vigorous development ince the 1930 s and 1940 s, the level of the discipline of the radiological health and the effectiveness of radiological hygiene work in China have been greatly improved at this stage. This paper provides a brief overview of the history, current status, and work content of the radiological health research and radiological hygiene work in China, with a view to contributing to the future development of radiological hygiene work in China.

Objective To obtain the medical exposure frequency data of residents through a questionnaire survey on mobile phone networks in the community, and to analyze the main influencing factors. Methods A snowball sampling method was used to expand the sampling from medical staff in a county hospital to the community. The questionnaire included personal information such as occupation category, type of medical insurance, and education level as well as basic radiation-related knowledge and medical exposure type and frequency of respondents received in 2021. A logistic regression model was used to analyze the influencing factors of medical exposure. Results A total of 223 respondents were investigated, and 12.56% of them received radiological diagnosis and radiotherapy in 2021. The proportion of males receiving medical exposure was significantly higher than that of females (19.64% vs 10.18%). The likelihood of the person receiving medical exposure increased considerably with age, with the proportion of residents receiving medical exposure at 20, 30, 40, and 50 years of age being 6.25%, 7.95%, 19.23%, and 33.33%, respectively. Of persons who received medical exposure, 57.14% underwent CT scans. Persons participating in the new rural cooperative medical system were likely less to receive radiological diagnosis and radiotherapy than urban workers and residents (OR = 0.55, CI:0.13-2.23, P > 0.05). Conclusion Questionnaire survey in the community can obtain more information about the medical exposure of residents, and age and type of medical insurance are important factors affecting the frequency of medical exposure.

Since the implementation of the Measures for the Management of Radiation Workers’ Occupational Health in November 2007, it has played an extremely important role in protecting the occupational health of radiation workers. There are more than 700 000 radiation workers in about 100 000 workplaces with potential radiation exposure, as well as a large number of miners exposed to high levels of radon. As the radiation health monitoring project suggests, measures of occupational health management such as personal dose monitoring and occupational health examination of radiation workers have been widely implemented and achieved good results in the protection of radiation workers. However, the risks of chromosomal aberration and specific turbidity of the eye lens of radiation workers have increased in high-risk positions such as interventional radiology, nuclear medicine, and industrial flaw detection. The control of high radon exposure in miners needs to be strengthened. It is necessary to adapt to the new situation in view of new challenges and actively promote the revision of the Measures for the Management of Radiation Workers’ Occupational Health, so as to further improve the occupational health management of radiation workers in China.

The purpose of establishing nuclear power plants is to meet the growing energy demand. Unfortunately, there have been five major nuclear accidents in history, which have diverse and lasting effects on individuals and society. The well-known health effects are tissue reactions caused by high radiation doses and carcinogenic effects of low radiation doses. In recent years, studies on adult residents, mothers with young children, and clean-up/decontamination workers exposed to high doses of radiation in the areas affected by nuclear power plant accidents show long-term impacts on the mental health of these people. This paper reviews these psychological impacts.

Objective To analyze the factors influencing the levels of occupational exposure in medical radiation workers in China, and to provide a scientific basis for determining the key points of radiation protection in the medical sector. Methods The individual monitoring data on occupational external exposure in medical radiation workers in 2021 were collected from the “National Individual Dose Registry”. The Chi-squared test and logistic regression were used to analyze the factors influencing the levels of occupational exposure in medical radiation workers. Results The Chi-squared test showed that gender, occupational category, medical institution category, region, number of radiation workers per thousand population, and regional per capita GDP were significantly associated with occupational exposure in medical radiation workers exceeding the annual effective dose of 5 mSv and an annual effective dose limit of 20 mSv (χ² = 21.456−262.329, 7.601−78.650, P < 0.05). The logistic regression analysis further showed that gender, occupational category, region, and number of radiation workers per thousand population were factors influencing the occupational exposure in medical radiation workers exceeding the annual effective dose of 5 mSv (χ² = 14.621−170.857, P < 0.05); gender, occupational category, region, and regional per capita GDP were factors influencing the occupational exposure in medical radiation workers exceeding the annual effective dose of 20 mSv (χ² = 5.401−48.709, P < 0.05). Conclusion Male radiation workers in interventional radiology and in central China have high risks of exceeding annual effective doses of 5 and 20 mSv. Moreover, high number of radiation workers per thousand population and regional per capita GDP are associated with low risks. Medical institutions should maintain a sufficient number of radiation workers and strengthen training on radiation protection knowledge for male and interventional radiology workers to enhance their radiation protection awareness. Investigation of the factors contributing to the high occupational exposure in central China should be intensified, and targeted effective measures should be conducted to reduce the occupational exposure in medical radiation workers.