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  • 28 February 2020 Volume 29 Issue 1
      
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  • Interpretation of diagnosis of occupational radiation skin diseases
    YANG Wenfeng, YANG Zhixiang, JIN Zengqiang
    2020, 29(1): 1-6. https://doi.org/10.13491/j.issn.1004-714X.2020.01.001
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    In this paper, the characteristics, clinical manifestations, diagnostic criteria and treatment principles of acute and chronic radiation skin injury caused by external irradiation were analyzed based on domestic and foreign literatures, newly formulated national occupational health standards and the author's clinical experience, etc., which provide basis for timely treatment and standardized diagnosis and treatment of radiation skin injury. Acute radioactive skin injury is divided into Ⅰ, Ⅱ, Ⅲ and Ⅳ degrees according to the size and clinical manifestations of the irradiated dose. The clinical course of these four degrees of acute radioactive skin injury not only showed the association between dosage and injury, but also showed the obvious phases of severe radiation injury. Early dose estimation through skin injury degree is helpful for rapid and accurate diagnosis, early prediction of lesion severity and decision of treatment strategy. Chronic radioactive skin injury is caused by long-term exposure to low-dose radiation due to occupational reasons; Another reason is prolonged formation of acute radioactive skin injury, which divided into Ⅰ, Ⅱ and Ⅲ degree. It is only classified according to the degree of skin injury and has no strict dose-effect relationship with the radiation received. The treatment of acute and chronic radioactive skin injury is different according to the degree of injury. Local conservative treatment and surgical treatment using repair methods all consider the promotion effect of systemic treatment on wound healing.
  • Effects of different dose ionizing radiation on the transcriptional level of DNA damage repair related genes in human peripheral blood lymphocytes
    CHEN Huifeng, TAN Siwen, YAN Xuehua, WANG Qia, YANG Yuhua, ZOU Jianming
    2020, 29(1): 7-12. https://doi.org/10.13491/j.issn.1004-714X.2020.01.002
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    Objective To investigate the effects of different dose ionizing radiation on the transcriptional level of DNA damage and repair related genes (hOGG1, MGMT, PPP2R1A and PPP2R2D) in human peripheral blood lymphocytes.Methods 30 mL peripheral blood was extracted from a volunteer and was subpackaged into seven heparin lithium-anticoagulant tubes. Human peripheral blood was irradiated by using 60Co-γ rays (doses of 0, 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2 Gy) at a dose rate of 0.38 Gy/min. Peripheral blood lymphocytes were isolated after 12 h and then total RNA was extracted for quantitative and purity analysis. Real-time fluorescence quantitative polymerase chain reaction method was used to analyze the changes of transcriptional level of hOGG1, MGMT, PPP2R1A and PPP2R2D gene.Results The transcription levels of hOGG1, MGMT and PPP2R2D gene all reached a peak of 0.1 Gy. The transcription level of PPP2R1A reached a peak of 0.2 Gy. Compared with the control group, the transcription levels of hOGG1 gene increased significantly at 0.1 Gy and 0.2 Gy(P < 0.05). The transcription levels of MGMT gene at 0.1 Gy, 0.2 Gy and 0.8 Gy were all significantly higher than that in the control group (P < 0.05). Compared with the control group, the transcription levels of PPP2R1A gene were increased significantly at 0.2 Gy (P < 0.05). Compared with the control group, the transcription level of PPP2R1A gene was decreased significantly at 3.2 Gy (P < 0.05). Compared with the control group, the transcription levels of PPP2R2D gene increased significantly at 0.1 Gy 0.2 Gy, 0.4 Gy and 0.8 Gy. Compared with the control group, the transcription level of PPP2R2D gene was decreased significantly at 3.2 Gy (P < 0.05).Conclusion Different dose ionizing radiation could induce changes in the transcriptional levels of the genes of DNA damage repair enzyme including, hOGG1, MGMT, PPP2R1A and PPP2R2D. Suitable low dose ionizing radiation (0.1~0.2 Gy) may induce radiation hormesis or adaptive response of cells.
  • Observation of chromosome aberration and micronucleus in interventional radiology workers
    NA Xiangjie, FU Lili, SHAN Tiemei, LI Yeming, SUN Sumei
    2020, 29(1): 13-16. https://doi.org/10.13491/j.issn.1004-714X.2020.01.003
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    Objective To investigate the effects of X-ray on chromosome and micronucleus of peripheral blood lymphocytes of interventional radiologists, and to ensure the health and safety of interventional radiologists.Methods 363 medical workers who were engaged in interventional radiology were selected as the study subjects and 435 health workers who were not exposed to radiation were selected as the control group.Results The total chromosome aberration rate (0.11% ±0.373%) in the interventional radiation group was significantly higher than that in the control group (0.02% ±0.126%), and the difference was statistically significant (t = 5.080, P < 0.01). Acentric fragment rate (0.04% ±0.199%) and bicentric fragment rate (0.06% ±0.234%) were also significantly higher than the control group (0.01% ±0.107%) and (0.00% ±0.068%), with statistically significant differences (t = 2.693,4.529 P < 0.01). The difference between the micronucleus rate (0.78‰ ±0.996‰) and the control group (0.65‰ ±0.853‰) was also statistically significant (t = 2.000, P < 0.05). There was no significant difference in chromosome aberration rate, acentric fragment rate and bicentric centromere rate between different working years (P > 0.05). The difference of micronucleus rate was statistically significant (P < 0.01). The difference of micronucleus rate between the group with working age ≥ 20a and other groups was statistically significant (P < 0.01). Intervention group and normal emission (diagnostic radiology, radiotherapy, industrial application) compared to the total chromosome aberration rate, double kinetochore rate differences were statistically significant (P < 0.01, P < 0.05), between two groups, intervention group (0.10 %±0.299%) total chromosome aberration rate is significantly higher than diagnostic radiology (0.06% ±0.312%) radiotherapy (0.03% ±0.170%) and industrial application group (0.04% ±0.189%), differences were statistically significant (P < 0.01), The rate of chromosome dicentriomere in the interventional group (0.06% ±0.234%) was significantly higher than that in the radiotherapy group (0.03% ±0.239%), the radiotherapy group (0.01% ±0.121%), and the industrial application group (0.02% ±0.135%), with statistically significant differences (P < 0.05). There was no significant difference in the rate of chromosome acentric fragment and micronucleus between the intervention group and each other.Conclusion X- ray can affect the rate of chromosome aberration and micronuclei. Long-term exposure to low doses of ionizing radiation can significantly increase the chromosome aberration rate and micronucleus rate of peripheral blood lymphocytes, which gradually increase with the increase of working age.
  • Analysis of occupational health examination results of radiation workers in Jiangsu Province in 2017
    XU Fang, WANG Furu, WANG Jin, CHEN Wei, YANG Xiaoyong
    2020, 29(1): 17-20. https://doi.org/10.13491/j.issn.1004-714X.2020.01.004
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    Objective To analysis the occupational health examination of radiation workers in Jiangsu Province in order to provide theoretical basis for the prevention and treatment of occupational radiation diseases.Methods A cross-sectional survey were carried out to analysis 5186 cases who took part in occupational health examinations in 2017. By using SPSS software and chi-square test, the abnormal rates of physical examination were measured in terms of sex, occupational hazard exposure length of service, type of work and physical examination. Results The study consisted of 3 516 men (67.8%) and 1 670 women (32.2%). Among them, 1 601 persons (30.9%) were involved in industrial applications and 1 843 persons (35.5%) were involved in medical applications, 593 workers (11.4%) engaged in other areas. Stratified analysis showed that the blood pressure, electrocardiogram (ECG), liver B-mode ultrasound, B-ultrasound of the liver and B-ultrasound of the liver had significant differences in the different background of gender, exposure years and physical examination item. There were significant differences in the abnormal rate of peripheral blood (except red blood cells) in different sex of radiation workers (P < 0.05). There was statistical significance of detection rate of hemoglobin abnormalities according to the years of service (P < 0.05).Conclusion Prolonged exposure to low dose radiation may affect the occupational health status of radiation workers . It is especially important to carry out occupational health management and examination regularly.
  • Head doses and effects of shielding for head CT scan of children phantom model
    ZHANG Yuheng, CHEN Yingmin, CHEN Rui, ZHAO Jianshe, LIU Zhaotian
    2020, 29(1): 21-25. https://doi.org/10.13491/j.issn.1004-714X.2020.01.005
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    Objective This study showed the effective dose and the absorbed doses of organs and tissues, and discussed the effects of shielding for head CT scan by using children phantom model.Methods This study simulated children head CT scan under clinical condition with Discovery CT 750 HD by setting the thermoluminescent dosimeters in one-year old and ten-year old phantom, gained the absorbed dose of organs and calculated effective dose in children under condition of 0.5 mmPb lead clothes wrapping shielding measure in non-scanning areas, and without taking any protective measures, and studied the shielding effect of lead clothes in children head CT examination.Results For the head CT examinations of the one-year old phantom, compared with no shielding, the doses of main organs such as thyroid, lung, stomach, intestine and breast, reduced at least 40.4%，and the effective dose reduced from 4.9 mSv to 2.2 mSv by 55.7%. For the head CT examinations of the ten-year old phantom, compared with no shielding, the doses reduced at least 39.5%, and the effective dose reduced from 2.4 mSv to 1.7 mSv by 30.5%.Conclusion Shielding protection can significantly decrease the effective dose and the absorbed dose of tissues and organs in children.
  • Analysis of CT machine quality control and radiation protection test results in Luoyang from 2016 to 2017
    WANG Xinai, WANG Haisheng, LI Ruzhen, LI Zhe
    2020, 29(1): 26-30. https://doi.org/10.13491/j.issn.1004-714X.2020.01.006
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    Objective Understand testing index of CT machine quality control and protection status of CT machine room in Luoyang city.Methods By random sampling method, 55 CT machines in 45 hospitals in Luoyang in 2016, 37 CT machines in 32 hospitals in Luoyang in 2017 were tested for quality control, radiation level around the machine room was detected, and the test results were analyzed and evaluated.Results The test results of quality control showed that the qualified rate in 2016 was 63.60% and that in 2017 was 89.20%, with statistically significant differences (P < 0.05). In 2016, the qualified rate of primary, secondary and tertiary hospitals was between 60.00% and 65.52%; in 2017, the qualified rate of primary hospitals was 78.90%; and the qualified rate of both secondary and tertiary hospitals was 100.00%. In 2016, the qualified rate of detection by a 16-row less CT machine was 51.85%, 70.60% by 16-row CT machine, and 81.80% by a 64-row CT machine or above. In 2017, the qualified rate of detection was 86.60%, 85.70% and 100.00% respectively. The qualification rate of the single index of the quality control test of the CT machine was 76.36% in 2016, while the rest were above 90.0%. The qualification rate of the single index in 2017 was all above 90.0%. According to the radiation level test results around the CT machine room, the qualified rate in 2016 was 98.04%, and the qualified rate in 2017 was 97.30%.Conclusion In 2016, the qualified rate of CT machine quality control in luoyang was relatively low. Although it was greatly improved in 2017, the supervision still needs to strengthen, with the emphasis on the supervision of primary and lower level hospitals.
  • Meta-analysis of cohort studies on radiation exposure from CT scans in childhood and subsequent cancer risk of leukaemia and brain tumors
    NIU Yating, SU Yinping, NIU Yantao, SUN Quanfu
    2020, 29(1): 31-36. https://doi.org/10.13491/j.issn.1004-714X.2020.01.007
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    Objective To quantitatively estimate the radiation exposure from CT scans in childhood and subsequent cancer risk of leukemia and brain tumors.Methods We retrieved six databases, including Wanfang Database, China National Knowledge Infrastructure, China Biology Medicine disc, MEDLINE, Pubmed, The Cochrane Library, and summarized large-scale cohort studies on CT scans in childhood and subsequent cancer risk which published at home and abroad before 2019. Meta-analysis was performed using relative risk (RR) and its 95% confidence intervals.Results There are five literatures included the analysis. The RR between leukemia and brain tumors was 1.59 (95% CI: 1.24, 2.05) and 2.07 (95% CI: 1.50, 2.86) respectively. CT scans increased the risk of leukemia and brain tumors.Conclusion Radiation exposure of CT scans in childhood can increase the risk of leukemia and brain tumors. It is important to reduce the radiation dose in children as much as possible without compromising the clinical diagnostic value of the image.
  • Study on the effective dose of chest DR at different kilovolt conditions using children's anthropomorphic phantom
    WANG Xiankai, LI Hailiang, CHEN Yingmin, ZHANG Lin, LIU Wei
    2020, 29(1): 37-39,44. https://doi.org/10.13491/j.issn.1004-714X.2020.01.008
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    Objective The absorbed dose of tissues and organs of the 1-year old children under different kilovolt conditions was measured by anthropomorphic phantom, and the effective dose under different kilovolt conditions was estimated and compared.Methods The thermoluminescence dosimeter (TLD) assembled in the plastic tube was placed into the socket reserved for the anthropomorphic phantom of children, and exposed 20 times at 60, 70, 80 and 90 kV respectively in the automatic exposure control (AEC) mode, then the TLD was recovered and measured in the laboratory. The absorbed dose of tissues and organs under different kilovolt conditions was calculated and the effective dose of children was estimated respectively.Results The absorbed dose of all tissues and organs in the radiation field decreases gradually with the increase of kilovolt at 60, 70, 80 and 90kV.The effective doses in the 4 experimental groups were 0.43, 0.34, 0.29 and 0.23 μSv respectively.Conclusion The use of higher kilovolt radiography in the chest of infants can reduce the absorbed dose of tissues and organs and the effective dose of the whole body.
  • The results analysis of individual monitoring status from occupational exposure in a hospital from 2007 to 2017
    SHI Mengdie, SHI Yu, MIN Zhiteng, HUANG Jing
    2020, 29(1): 40-44. https://doi.org/10.13491/j.issn.1004-714X.2020.01.009
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    Objective To analyze the individual dose level of radiation workers of different types of occupational external exposure in a hospital from 2007 to 2017, to ensure the health of radiological workers and provides a reliable basis for the radiology management work of hospital administrative departments.Methods Based on the relevant national laws and regulations and health standards, the results of personal dose monitoring were evaluated by thermoluminescence measurement, and SPSS22.0 statistics analysis for radiology, interventional radiology, radiotherapy, and other medical personnel.Results A total of 666 man-time were monitored, with an annual effective dose per capita of 0.62 mSv·a-1. The collective dose were 34.51 man·mSv. The highest annual effective dose per capita in 2010 was 1.08 mSv·a-1. In 2011, large-dose values accounted for the highest proportion, reaching 18.9%; the large doses of intervention staff accounted for 53.5% of the total staff. The maximum number of monitoring interventional radiology workers was 263 man-time, and the average annual effective dose per capita was the highest, 0.82 mSv·a-1, with statistically significant differences in different types of work (P < 0.05).Conclusion The exposure dose of radiation workers in the hospital meets the requirements of the national occupational exposure limit, and the exposure dose of radiation workers was low and decreasing year by year. The interventional radiology was still a high-risk radiation position, and the personal protective awareness needs to be improved. Radiographers and nursing staff were highly mobile, so it is necessary to strengthen radiation protection training for such people.
  • Comparison and analysis of the intercomparison results of national personal dose monitoring from 2016 to 2018
    ZHAI Hezheng, DU Zhongqing, WU Xiangjun, WANG Qiaojuan, ZHANG Wenyi, WANG Xin, RUAN Shuzhou, WU Quan
    2020, 29(1): 45-48. https://doi.org/10.13491/j.issn.1004-714X.2020.01.010
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    Objective To participate in the national ability assessment of personal dose monitoring, understand the performance of personal dose monitoring system and the level of technical personnel, and improve the ability of personal dose monitoring and the accuracy of data.Methods According to GBZ 207—2016 and the evaluation plan, seven groups of personal dosimeters were prepared to carry out personal dose monitoring ability assessment and data analysis in 2016—2018, the uncertainty of the measurement results was evaluated and the results were compared with the reference value.Results The single group performance results of personal dose monitoring ability assessment were −0.02～0.20, and the comprehensive performance result was 0.14, which was qualified in 2016, and the single group performance results of personal dose monitoring ability assessment were −0.01～0.02, and the comprehensive performance result was 0.02, which was excellent in 2017. At last, the single group performance results of personal dose monitoring ability assessment were −0.01～0.02, the comprehensive performance result was 0.01 and the result is excellent in 2018.Conclusion The data processing of personal dose monitoring in our laboratory was standardized, and the results were accurate and reliable, which met the requirements of relevant national standards. It is necessary and important to improve the ability of personal dose monitoring, strengthen quality control and actively participate in personal dose ability assessment.
  • Study on α radioactive surface contamination simulation method based on NdFeB magnetic powder
    WANG Qi, JI Yunlong, LI Dawei, WANG Xiaoning, NING Jing
    2020, 29(1): 49-52,56. https://doi.org/10.13491/j.issn.1004-714X.2020.01.011
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    Objective To develop a safe and reliable simulative source for nuclear emergency medical assistance training.Methods α surface sources are measured by a portable α surface radioactivity detector to summarize the correlations. A magnetic field is used to simulate the α-radiation field, and NdFeB magnetic powder is used as the magnetic source. Magnetic powder mixed with colloid is magnetized in a magnetic field to prepare magnetic powder colloid. The magnetic powder colloid is applied to the surface of an object as a simulated source. A specific detection circuit is designed to detect the simulated source. By using a certain conversion formula, voltage value is converted into count rate or an activity value to simulate the α surface contamination.Results The count rate of the α surface source measured by the portable α detector shows a linear relation with the measuring distance within the range of the α beam. The simulated source prepared by using NdFeB magnetic powder and colloid has the properties of α surface contamination, and can simulate a real measurement of α surface radioactivity within the range of 0.5～3 cm. Besides, signal decrease in process of decontamination can also be simulated.Conclusion The α radioactive surface contamination simulation method based on NdFeB magnetic powder is safe and reliable, and has no radiation hazard. It can be applied to the training of α surface radioactivity detection and decontamination, which has certain practical value for improving the training level and consequently improving the actual assistance ability of the nuclear emergency assistance team.
  • Measurement and protection evaluation of pulsed X-ray radiation field induced by a certain equipment
    LI Dawei, JI Yunlong, ZHOU Hongmei, XIE Xiangdong, WANG Changzhen, DONG Guofu, ZHAO Xuelong, WANG Qi, NING Jing
    2020, 29(1): 53-56. https://doi.org/10.13491/j.issn.1004-714X.2020.01.012
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    Objective To investigate the ionizing radiation levels of pulsed X-ray at different positions under experimental conditions of a certain equipment, and to propose appropriate protective suggestions.Methods Thermoluminescence measurement method is adopted. Thermoluminescence dosimeters were set up in different directions and distances around the equipment cabin, and were measured after a certain amount of pulsed radiation was accumulated. X-ray and gamma ray ionizing chamber dosimeter (FJ-347A) was used for real-time measurement of the dose rate of ionizing radiation at different distances. Recommendations on radiation protection at different working positions were made according to the individual dose limits for occupational exposure personnel and members of the public stipulated in the “Basic standards for protection against ionizing radiation and for the safety of radiation sources” (GB 18871—2002).Results Thermoluminescence dosimeters received 3000 radiation pulses accumulatively. The dose received by the thermoluminescence dosimeters on the outside wall of the equipment cabin ranged from 0.01 mGy to 8.98 mGy, the roof ranged from 0.01 mGy to 15.67 mGy, 1～12 meters from the outside wall ranged from 0.01 mGy to 2.18 mGy, and work stations was 0 mGy. Under the working condition, the range of air kerma rate measured by the X-ray dosimeter between 1～20 meters from the outside wall of the equipment cabin was 0.26～16 mGy/h.Conclusion The results of thermoluminescence dosimeters and ionizing chamber dosimeter are basically consistent, indicating that both methods can be used for pulsed X-ray measurement. In working condition, the radiation dose rates in short distance outside the cabin of the equipment are relatively high. Radiation protection requirements can be met by taking safety protection measures or limiting the workload of personnel.
  • Investigation and analysis of radon concentration in a mining area in Yunnan Province
    SUN Lu, WANG Xiaochun, PAN Yan, CUI Hongxing, WU Yunyun, LIU Jianxiang
    2020, 29(1): 57-60. https://doi.org/10.13491/j.issn.1004-714X.2020.01.013
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    Objective To investigate the radon concentration in the indoor air and tap water of a tin mine, a copper mine and a non-mining area in Yunnan Province, and to estimate the human exposure dose caused by radon.Methods Radon concentrations in underground and above-ground workplace air of tin and copper mines were measured by Track method, radon concentration in indoor air and radon concentration in tap water were measured by RAD7 continuous measurement method. The contribution of different radon doses was evaluated.Results The average radon concentrations in the underground and above ground workplaces air of tin mine are (7 473 ±3 105) Bq·m−3 and (332 ±238) Bq·m−3 respectively, and the annual dose contributions are (29.44 ±12.23) mSv and (2.50 ±1.79) mSv correspondingly; the radon concentrations in the air of the underground and above ground workplaces of copper mine are (4 477 ±5 152) Bq·m−3 and (110 ±32) Bq·m−3 respectively, and the annual dose contribution is (17.64 ±20.30) mSv and (0.83 ±0.24) mSv correspondingly; and the radon concentration in indoor air (76 ±33) Bq·m−3 and the annual dose contribution (2.01 ±0.87) mSv. The radon concentrations in tap water of copper mine and tin mine are (1.66 ±2.00) Bq·L−1 and (3.94 ±1.81) Bq·L−1 respectively, higher than the value of (0.39 ±0.21) Bq·L−1 in tap water of 32 sampling points in the city.Conclusion The dose contribution caused by radon in water is relatively small, the concentration of radon in the underground workplace of tin and copper mine is worthy of attention. Attention should be paid to publicizing and education of use of protective equipment for miners.
  • Analysis of 210Po in stone coal material from a vanadium extracting plant
    ZHANG Yanqi, PAN Jingshun, PAN Ziqiang, LIU Senlin, ZHANG Yimin, LIAO Haitao, CAI Zhenlei, HU Pengcheng, HUANG Juan
    2020, 29(1): 61-64. https://doi.org/10.13491/j.issn.1004-714X.2020.01.014
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    Objective It is to establish an analysis method and to analyze the activity concentration of 210Po in stone coal.Method Stone coal ore samples were collected from a raw material workshop of a vanadium extracting plant in which vanadium is extracted from stone coal by a pyro -hydro process. Standard 209Po was used as tracer, and the stone coal samples were wet-digested into acid and auto deposited on silver disks.Results The average activity concentration of 210Po in stone coal samples was 359.5 ±7.6 Bq·kg−1, with the 2.1% total relative error. The full recovery rate was 60.0% ±3.2%. The detection limit of the method was 1.8 Bq·kg−1, while the measurement time was 48 h.Conclusion 210Po activity concentration in stone coal is relatively high. Therefore, further studies are needed on the transfer, enrichment and emission of 210Po, as well as the corresponding issue on radiological impacts, during vanadium extracting by the pyro -hydro process from stone coal.
  • Discussion on some key issues in radiation environmental impact assessment of high energy proton therapy system
    JIN Xiao, YAN Yuan, HAN Chuncai
    2020, 29(1): 65-68. https://doi.org/10.13491/j.issn.1004-714X.2020.01.015
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    Objective To analyze some key issues in radiation environmental impact assessment of high energy proton therapy system and present the proposals for the reference of environmental impact assessment of such nuclear technology utilization activities.Methods Taking a recent radiation environmental impact of proton therapy system as a case study, the key issues and corresponding proposals were present from the aspects of radiation pollution source items, radiation shielding calculation and evaluation, induced radioactivity analysis, and exposure dose calculation of pesonnel.Results In radiation environmental impact assessment of proton therapy system, more emphasis should be placed on the entrance of the inner maze wall and gantry area of the gantry room that lies next to the rotating beam therapy room when determining the dose rate limits of area outside the shielding of radiation workplace. In addition to common factors such as air, cooling water, structure items, concrete walls, soil and underground water, it is also important to pay attention to patient-induced radioactivity in treatment room when analyzing the induced activity. Besides the external irradiation dose, the dose contribution of induced radioactivity in treatment room should be taken into account when estimating the exposure dose of the radiation workers.Conclusion As a large-scale medical equipment, environmental impact assessment of high energy proton therapy system should be done scientifically and objectively, taking various influence factors into consideration.
  • Investigation and analysis of the basic situation of clinical radiation workers in Mianzhu
    LONG Yiqian, MENG Qingchun, LI Tao
    2020, 29(1): 69-71,75. https://doi.org/10.13491/j.issn.1004-714X.2020.01.016
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    Objective To understand the basic situation of radiation workers in the city and to provide suggestions for optimizing the structure of radiation personnel, improving the quality of radiation exposure, and improving the level of radiation protection.Methods A general survey was conducted to collect the basic information of 134 radiation workers from 41 radiological clinics institutions in mianzhu city.Results The personnel engaged in diagnostic radiology accounted for 87.31%, and those engaged in interventional radiology accounted for 12.69%.; The median age of male radiation workers was 42 years and that of female radiation workers was 35 years. There was a statistically significant difference in academic qualifications between those engaged in diagnostic radiology and those engaged in interventional radiology;With the increase of organization level, the higher the professional title and education background of radiation workers, the smaller the length of radiological service, the younger the age,and the more reasonable the structure.Conclusion The education background of the radiation workers in this city has improved somewhat after the "5.12" earthquake. However the overall educational structure and professional titles are relatively lagging behind. Radiation workers has low professional conformity. The structure of interventional radiologists is superior to that of diagnostic radiologists；There is a shortage of radiological technicians in primary medical units..The key to improving the level of local radiology and treatment and improving the protection status is to solve the problem of "talent".
  • The current situation and countermeasure of radiodiagnosis and radiotherapy resources allocation in Ningxia
    DONG liang, YIN Jie, JI Xuli, SUN Yanling, LI Hongcheng, LU Guicai
    2020, 29(1): 72-75. https://doi.org/10.13491/j.issn.1004-714X.2020.01.017
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    Objective To master the situation of radiological diagnosis and radiotherapy resources allocation in Ningxia, and to provide scientific policy data for the health administration department to further optimize the medical resources allocation.Methods Combining the methods of distributing questionnaire and field investigation.Results There are 928 sets of radiological diagnosis and treatment equipment in Ningxia, including 883 sets of X-ray imaging diagnosis equipment, 8 sets of radiotherapy equipment, 33 sets of interventional radiology equipment and 4 sets of nuclear medicine equipment. And there are 1, 676 radiological staff with a certification rate of 99.64%. On average, there are 1.36 sets of radiological diagnosis and treatment equipment per 10, 000 people, of which 45.91% are distributed in Yinchuan city, and the remaining 4 cities are significantly less distributed. In addition, interventional radiology equipment accounts for about 50% in Yinchuan city, and radiotherapy equipment and nuclear medicine equipment are only distributed in Yinchuan.Conclusion The overall allocation of radiological diagnosis and treatment equipment resource in Ningxia is backward and uneven. Most of the resources are concentrated in Yinchuan City, especially the high-end equipment such as radiotherapy and nuclear medicine equipment.
  • Research on patient dose in 18F-FDG and 18F-FET PET-CT examinations
    LI Ning, HE Zhengzhong, YANG Zhi, YANG Hongyu, LIAO Guangxing, LUO Yu, CHAI Hua, LI Dangsheng, XIAO Guoyou
    2020, 29(1): 76-80,84. https://doi.org/10.13491/j.issn.1004-714X.2020.01.018
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    Objective To estimate the effective and organ dose of patients receiving the 18F-FDG (18F-2-deoxy-D-glucose) and 18F-FET (O-2-18F- fluoroethyl -L-tyrosine) PET-CT whole body examinations.Methods Two PET-CT scanning protocols were used for whole body imaging. The effective and organ dose of PET part were calculated using the internal dose computer program IDAC 2.1 based on MIRD method. The effective and organ doses of CT part were calculated by VirtualDose software, and the sum of CT and PET dose was the total effective dose of patients.Results In the conventional PET-CT scan protocol, the effective dose was (4.81 ±1.04) mSv for male and (6.09 ±0.73) mSv for female patients from 18F-FDG; the effective dose was (2.67 ±0.38) mSv for male and (3.21 ±0.38) mSv for female patients from 18F-FET; the effective dose was (5.63 ±0.32) mSv for male and (5.51 ±0.29) mSv for female patients from CT component. The total effective dose was (10.44 ±1.09) mSv for male and (11.60 ±0.79) mSv for female from 18F-FDG PET-CT examination, respectively. Whereas it was (8.30 ±0.50) mSv for male and (8.72 ±0.49) mSv for female from 18F-FET PET-CT examination, respectively. In the diagnostic-quality CT scan protocol, the effective dose was (16.28 ±1.01) mSv for male and (13.49 ±0.72) mSv for female patients from CT component. The total effective dose was (21.09 ±1.45) mSv for male and (19.58 ±1.03) mSv for female patients from 18F-FDG, respectively. Whereas it was (18.95 ±1.08) mSv for male and (16.70 ±0.81) mSv female patients from 18F-FET.Conclusion Different PET-CT scan parameters caused the patient to be exposed to different radiation doses. In the daily work, we should optimize the acquisitive parameters of PET and CT according to the actual situation of the examinee, and reduce the dose of examinee to practice the optimization of radiation protection.
  • Dosimetry comparison of partial-arc and full-arc volumetric modulated arc therapy for middle esophageal cancer
    ZHANG Huiling, LI Xin, WU Xiaoliang, XU Huijun, ZHANG Wei, MA Zhiqian, LIU Chaoxing
    2020, 29(1): 81-84. https://doi.org/10.13491/j.issn.1004-714X.2020.01.019
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    Objective The study was performed to compare the dosimetric differences of different volumetric modulated arc therapy (VMAT) (full-arc VMAT and partial-arc VMAT) for middle esophageal cancer, and explore the feasibility of partial-arc VMAT in treatment.Methods Two plans were designed for 11 patients with middle esophageal cancer, including partial-arc VMAT and full-arc VMAT plan. The dosimetric differences of the parameter of the planning target volume (PTV), organs-at-risk (lung, spinal cord, and heart) and monitor units (MU) were compared. Paired t-test analysis was performed on the two groups of data using SPSS 17.0 software.Results The full-arc VMAT plan was superior to partial-arc VMAT plan in PTV D95 (t = - 7.699, P = 0.000), D98 (t = - 6.384, P = 0.000) and homogeneity index (HI)(t = 10.423, P = 0.000). The partial-arc VMAT plan was better than the full-arc VMAT in the V5 of lungs (t = - 4.048, P = 0.002). There was no significant differences were found in the conformity index and homogeneity index of PTV, the V10, V20 of lungs (P > 0.05).Conclusion The partial-arc VMAT and full-arc VMAT plan met the clinical requirement for middle esophageal cancer, while the partial-arc VMAT can significantly reduce the dose to low dose area in lungs.
  • Clinical application value of oral panoramic X-ray and low-dose CT in diagnosis of acute traumatic dislocation in permanent central incisor
    MA Xuemei, ZHANG Honghua, ZHENG Lei
    2020, 29(1): 85-88,92. https://doi.org/10.13491/j.issn.1004-714X.2020.01.020
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    Objective To investigate the application value of oral panoramic X-ray and low-dose CT in diagnosis of acute traumatic dislocation in permanent central incisor.Methods 78 patients (312 teeth) who were diagnosed as acute traumatic dislocationin permanent central incisor were reviewed. All cases were examined by panoramic X-ray and low-dose CT (for isotropic volume scanning, multiplanar reconstruction (MPR) and curve planar reformation (CPR)). The sensitivity, specificity and accuracy were evaluated by oral panoramic X-ray and low-dose CT.Results In panoramic X-ray，acute traumatic dislocation in permanent central incisor was clearly diagnosed in 77 teeth, 14 teeth were missed diagnosis and 18 teeth were misdiagnosed. After low-dose CT examination, acute traumatic dislocation in permanent central incisor was clearly diagnosed in 86 teeth, 5 teeth were missed diagnosis and 7 teeth were misdiagnosed. The sensitivity, specificity and accuracy were 84.6%, 91.9% and 89.7% in oral panoramic X-ray and 94.5%, 96.8% and 96.2% in low-dose CT, respectively. The differences were statistically significant in the sensitivity (χ2 = 4.76, P = 0.029)、specificity (χ2 = 5.13, P = 0.024）and accuracy (χ2 = 9.781, P = 0.002) between panoramic X-ray and low-dose CT.Conclusion Low-dose CT can display acute traumatic dislocation in permanent central incisor clearly. Compared with panoramic X-ray, low-dose CT can markedly increase the detection rate.
  • Dosimetry comparison of the 5-field IMRT and VMAT planning for esophageal carcinoma
    SHI Tingting, HAN Jihua, ZHANG Yan, ZHANG Xiaoye, ZHU Zhijian, HONG Jun
    2020, 29(1): 89-92. https://doi.org/10.13491/j.issn.1004-714X.2020.01.021
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    Objective To compare the dosimetric differences between fixed 5-field radiation therapy and volumetric modulated arc therapy for middle and upper esophageal carcinoma.Methods 20 cases of middle and upper esophageal carcinoma patients treated in our department from October to December, 2018 were selected as the study objects. We designed 5-field IMRT plan,VMAT1 plan and VMAT2 plan for each esophageal carcinoma patients respectively with Monaco5.11 planning system. The dosimetric differences of maximum target area and organ at risk in the three groups were evaluated by dose volume histogram (DVH) in the case which the target area dose coverage is 95%.Results Homogeneity Index (HI) of Single arc VMAT1 plan and Conformity Index (CI) of 5-field IMRT plan was better than the other two (P < 0.05).The maximum and average dose in the target area of 5-field IMRT plan is the minimal. In terms of organs at risk, the 5-field IMRT plan was superior to the other in reducing the maximal dose to the spinal cord and the average dose of the heart Single arc VMAT1 plan had the best protection for lungs, and double arc VMAT2 plan had advantage on the protection of heart V30 and V40. In terms of the number of monitor units, the fixed 5-field intensity control machine has the least monitor units, followed by single-arc VMAT1, and double-arc VMAT2 machine has the most monitor units.Conclusion 5-field IMRT plan could meet the clinical therapy needs for upper and middle Esophageal carcinoma radiotherapy. It has such advantages as lower maximal dose to the spinal cord and the average dose of the heart, better Conformity Index(CI) of target area and fewer monitor units.
  • Advances in experimental research on radiation-induced heart injury in animal models
    LI Peng, CHEN Fan, SUN Xiangyi, WANG Bing, YANG Mei
    2020, 29(1): 93-97. https://doi.org/10.13491/j.issn.1004-714X.2020.01.022
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    When radiation was used for the treatment of chest malignant tumor, the heart will be irradiated inevitably, which led to radiation-induced heart disease (RIHD). With the improvement of radiotherapy and chemotherapy, the survival time of cancer patients had been extended Therefore, the research on RIHD had been attracted more and more attention. At present, scholars have not formed a unified understanding of this diseaseand there is no effective method to prevent its occurrence in clinical practice at home and abroad. Animal model research can provide reliable evidence for clinical treatment and prevention of this disease. For this reason, this paper reviews and analyzes the animal model research of radioactive heart injury in recent years, which aiming to provide reference for the development of follow-up experiments and clinical application.