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  • Original Articles
    Adaptive response of A549 cell apoptosis induced by low-dose X-ray irradiation
    YU Xiaoling, RONG Li, FANG Fang, DING Xiaowen, LI Jue, WANG Xiaochun
    2022, 31(2): 139-143,148. https://doi.org/10.13491/j.issn.1004-714X.2022.02.001
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    Objective To study the adaptive response and time effect of A549 cell apoptosis induced by low-dose X-ray irradiation, and to preliminarily explore the possible mechanism of adaptive effect.Methods A549 cells were irradiated with X-ray of 50 mGy, 200 mGy and 500 mGy, respectively, and then irradiated with an effect dose of 20 Gy after intervals of 3 h, 6 h, 12 h, 24 h and 48 h, respectively, for cell apoptosis detection. The cell cycle distribution and DNA damage were detected after an interval of 6 h between the initial dose and the effect dose. 20 Gy and 0 Gy were set as the control. Results After irradiation at 20 Gy at intervals of 3 h, 6 h, 12 h and 24 h from the low-dose irradiation, the apoptosis rates of the 50 mGy～20 Gy, 200 mGy～20 Gy, and 500 mGy～20 Gy groups were significantly lower than that of the 20 Gy group (P < 0.05); after an interval of 48 h, there was no significant difference in the apoptosis rate between the 50 mGy～20 Gy, 200 mGy～20 Gy, and 500 mGy～20 Gy groups and the 20 Gy group. After an interval of 6 h between the low-dose irradiation and the effect dose irradiation, the percentage of cells at G0/G1 phase in the 50 mGy～20 Gy and 200 mGy～20 Gy groups was significantly lower than that in the 20 Gy group (P < 0.05); the percentage of cells at G2/M phase in the 50 mGy～20 Gy and 200 mGy～20 Gy groups were significantly reduced compared with the 20 Gy group (P < 0.05). There was no significant difference in the percentage of cells at G0/G1 and G2/M phases between the 500 mGy～20 Gy and 20 Gy groups. Compared with the 20 Gy group, the cell DNA damage in the 50 mGy～20 Gy, 200 mGy～20 Gy and 500 mGy～20 Gy groups were decreased, but without significant difference. Conclusion Low-dose X-ray irradiation can induce the adaptive response of A549 cells apoptosis, which is related to the time interval between the initial dose and the effect dose. The adaptive effect may be related to the changes in cell cycle induced by low-dose X-ray.
  • Original Articles
    Shielding performance of six different types of concrete in proton therapy room
    XU Zhiqiang, GENG Jiwu, JIA Yuxin, ZHANG Zaoqin, WANG Meixia
    2022, 31(2): 144-148. https://doi.org/10.13491/j.issn.1004-714X.2022.02.002
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    Objective To study the dose level of proton beams outside the main shield of the 230 MeV proton therapy room with six different types of concrete as the main wall, and to obtain the shielding performance of six different types of concrete. Methods The FLUKA program was used to build a calculation model, and different concrete compositions were introduced into the FLUKA program to simulate the change in ambient dose equivalent rate of the focus with concrete thickness under 230 MeV proton beam irradiation. The transmission curves of six different types of concrete were fitted to obtain shielding performance parameters. Results On the condition that the 230 MeV proton beam irradiated to the water target in 90° direction and the concrete thickness exceeded 40 cm, the proton beam was exponentially decayed for six different types of concrete, and the fitted decay curves had a R2 of > 0.99. The linear attenuation coefficients for normal concrete, barite concrete, magnetite concrete, limonite concrete, phosphorite concrete, and ferrosilicate concrete were 0.0148 cm-1, 0.0172 cm−1, 0.0196 cm−1, 0.0219 cm−1, 0.0256 cm−1, and 0.0290 cm−1, respectively. Conclusion The composition and proportion of elements in concrete materials directly affect the shielding ability of concrete against proton beams to a large extent, and the shielding performance of six different types of concrete against proton beams varies greatly. Therefore, shielding materials for the proton therapy room should be selected by a comprehensive consideration of the material compositions and shielding performance of concrete, the difficulty of construction, and construction cost.
  • Original Articles
    Application and analysis of radon-reduction methods in indoor radon pollution control
    KOU Shanshan, WU Yunyun, SONG Yanchao, ZHANG Qingzhao
    2022, 31(2): 149-152. https://doi.org/10.13491/j.issn.1004-714X.2022.02.003
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    Objective To investigate the suitable methods for reducing the concentration levels of residential radon and its daughters.Methods Three rooms were selected and treated by natural ventilation, air purifier, and sealing/shielding, respectively. The EQF3120 device was used to measure the concentrations of radon and its daughters, and the alpha nuclear trail detector was used to measure indoor radon concentration. The three methods were compared in terms of radon reduction effect. Results After natural ventilation for 2-10 hours, the average reduction rates of the concentrations of radon and attached and unattached radon daughters in the room were 87.7%, 89.8%, and 93.7%, respectively; in the room with air purifier, the concentrations of radon and attached and unattached radon daughters were reduced by 46.3%, 94.5%, and 45.3%, respectively; after sealing and shielding, the concentration of radon was reduced by 74.9% after 1 month and 59.2% after 1 year. Conclusion All three methods have a marked effectin reducing the concentrations of indoor radon and its daughters, and natural ventilation is the most economical and effective method for reducing radon.
  • Original Articles
    Dose level of pediatric CT scanning in a hospital
    WANG Yuenan, WANG Yan, DU Xiaohong, SHI Xiaoting, LIU Lantao
    2022, 31(2): 153-156. https://doi.org/10.13491/j.issn.1004-714X.2022.02.004
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    Objective To investigate the dose level of pediatric CT scan in one hospital, and to provide recommendations for optimized scanning.Methods The CT scan data of children were collected from this hospital to analyze the differences in typical dose values and typical scanning parameters between different age groups and different scanning parts. Results The sample size was >10 for routine cranial scan, routine maxillary sinus scan, and routine chest scan in each age group, and the 1-year-old group and the 5-year-old group had the same kV, mA, and CTDIvol values of routine cranial scan and maxillary sinus scan, but with relatively great differences in the parameters of chest scan. Conclusion Scanning parameters in this hospital can be further optimized, and optimization measures should be adopted continuously.
  • Original Articles
    Current situation and analysis of radiological diagnosis and treatment resources in Inner Mongolia Autonomous Region, China, 2019
    ZHANG Shuai, Haribala, Gerilemandahu, XU Xiao, SUN Zhichao, WANG Chengguo, DENG Jun
    2022, 31(2): 157-162. https://doi.org/10.13491/j.issn.1004-714X.2022.02.005
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    Objective To comprehensively obtain the present situation of medical radiation protection resources by investigating the basic information of all medical institutions in Inner Mongolia Autonomous Region, China from 2017 to 2019. Methods An investigation was conducted on the basic information of medical institutions according to the unified plan of medical radiation protection monitoring project issued in Inner Mongolia Autonomous Region, involving all radiodiagnostic medical institutions throughout the region.Results By the end of 2019, there were 1195 radiological diagnosis and treatment institutions, 7285 radiation workers, 2705 sets of radiological diagnostic equipment, 36 medical accelerators, and 22 sets of nuclear medicine equipment in the whole region.Conclusion The radiological diagnosis and treatment resources in Inner Mongolia Autonomous Region are developing rapidly. However, the problems of insufficient per capita resources and uneven development among the cities are becoming increasingly prominent.
  • Original Articles
    A survey of the frequency of medical exposure in Fangshan District of Beijing, 2019
    SU Dewen, LIU Tie, LIU Xiaoling, MA Changqing
    2022, 31(2): 163-166. https://doi.org/10.13491/j.issn.1004-714X.2022.02.006
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    Objective To investigate the basic situation of radiodiagnosis and radiotherapy institutions and the frequency of medical exposure in Fangshan District, Beijing, China. Methods A general survey using the questionnaire was conducted online to obtain the basic situation of the radiodiagnosis and radiotherapy institutions, the number of people in each type of radiodiagnosis and radiotherapy project, and the number of the usually resident population in the whole district in 2019, thus obtaining the frequency of medical exposure in each type of radiodiagnosis and radiotherapy project.Results There were 60 radiodiagnosis and radiotherapy institutions, 565 radiology staff, and 199 sets of radiodiagnosis and radiotherapy equipment in the whole district in 2019. The frequency of medical exposure was 521.29 per 1000 people, among which conventional medical diagnostic X-ray workers accounted for 301.79 per 1000 people (57.89%) and computed tomography workers accounted for 207.56 per 1000 people (39.82%). The number of tertiary hospitals accounted for 6.67% of the radiodiagnosis and radiotherapy institutions, and the number of people exposed tomedical radiation in tertiary hospitals accounted for 52.25% of the total. The number of secondary hospitals accounted for 5.00% of the radiodiagnosis and radiotherapy institutions, and the number of people exposed to medical radiation in secondary hospitals accounted for 27.83% of the total. Conclusion The distribution of medical exposure in Fangshan District is uneven. The radiodiagnosis and radiotherapy technology used is relatively single. Relevant departments should strengthen macroscopic readjustment and control, and formulate reasonable policies, so as to rationally allocate and effectively utilize medical and health resources.
  • Original Articles
    Radiation dose estimation and protective measure discussion of 241Am-Be neutron source logging
    FU Yaping, YAN Yuan, YU Zhengwei, CHEN Liangping, KONG Linghai, SUN Peng
    2022, 31(2): 167-171,180. https://doi.org/10.13491/j.issn.1004-714X.2022.02.007
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    Objective To investigate the radiation dose to operators in the process of 241Am-Be neutron source logging, and discuss neutron source management and protective measures for operators in well logging. Methods Through on-site observation and measurement of 241Am-Be neutron source logging in a company, we obtained the surface γ dose rate and neutron dose rate of the neutron source, as well as the operating time and distance of various processes including source taking, transfer, and loading, calculated the radiation dose to operators in various processes, and analyzed the source and proportion of the personal effective dose to operators. Results The effective doses of neutron irradiation and γ irradiation were 94.17 μSv and 2.72 μSv, respectively, for the combined processes of source tank inspection, transfer, and detection; 36.66 μSv and 24.08 μSv, respectively, for source loading and unloading; and 130.83 μSv and 26.80 μSv, respectively, for the whole neutron source logging process. The total annual effective dose of neutron source logging was 15.78 mSv, as estimated by logging 100 times per year. Conclusion In the process of 241Am-Be neutron source logging in the company, the effective dose to operators mainly arises from neutron irradiation. Therefore, it is necessary to strengthen neutron source management and take effective protective measures against neutron radiation.
  • Original Articles
    Computational fluid dynamics analysis of influence of different pipe structures on gas mixing uniformity
    ZHENG Jin’ge, CHENG Weiya, WANG Chenxiao, HAO Guizhen, LIU Weifu, GUO Haocheng, ZHAO Yulun, CHEN Ling
    2022, 31(2): 172-180. https://doi.org/10.13491/j.issn.1004-714X.2022.02.008
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    Objective Tostudy the influence of pipe structures on the mixing uniformity of airborne effluents from nuclear power plant chimneys. Methods We used the computational fluid dynamics (CFD) method to simulate the velocity distribution and gas mixing in long straight pipes (I type) with square section and circular section, 90° single-bend pipes (L type) with square section and circular section, and 90° double-bend pipes (S type and U type) with square section and circular section. Results For the long straight pipe, due to the lack of flow disturbance caused by structural changes, the mixing effect was not good; when the pipe section was circular, it might take mixing distance 20 times the hydraulic diameter to achieve the uniformity index required by the relevant standard; for the square pipe, the distance might be longer. In the single bend pipe with square section, the velocity uniformity was improved more greatly after the bend, and the tracer gas met the mixing uniformity at a shorter distance (11 times the hydraulic diameter), as compared with the single bend pipe with circular section. For the S-type double-bend pipe, the tracer gas appeared uniformly mixed after a distance 6 times the hydraulic diameter in the square pipe, and 7 times the hydraulic diameter in the circular pipe. For the U-type double-bend pipe, the gas in the square pipe also achieved uniform mixing ata shorter distance downstream, and the airflow showed greater disturbance when passing through the bend.Conclusion The CFD method can make an accurate prediction for the change patterns of gas mixing uniformity in pipes with different structures, and can partially replace physical experiments to study the factors affecting the mixing uniformity of airborne effluents from the chimney of nuclear power plants.
  • Original Articles
    Investigation on the radiation of 131I in treatment site of a grade A tertiary hospital
    LI Sijia, HAN Yufu, WANG Hualin, LIU Libo, CHEN Dawei, HE Qiang
    2022, 31(2): 181-185,203. https://doi.org/10.13491/j.issn.1004-714X.2022.02.009
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    Objective To detect the radiation of 131I in treatment site of a grade A tertiary hospital. Methods A total of 25 patients with thyroid cancer were administrated 131I at a total dose of 82880 MBq. After administration, the ambient dose equivalent rate of the ward was detected with X- and γ-ray detectors. After patient discharge, surface contamination of the ward was detected with α/β surface contamination meter. During patient hospitalization and on the day of discharge, air samples were collected from 131I treatment site and office area. The air samples were measured using a HPGe γ-ray spectrometer and the concentration of 131I in air was calculated. Results The ambient dose equivalent rate in the ward ranged from 0.15 to 0.46 μSv/h. Before ward cleaning, surface contamination ranged from 0.53 to 40.1 Bq/cm2 and the highest value was recorded on the toilet. Within 4 h after administration, the concentrations of 131I in air in treatment site and the corridor of the office area were 1.74 Bq/m3 and 0.66 Bq/m3, respectively. The ventilation air flow rate in the treatment site was 0.50 m/s. Ventilation decreased the concentration of 131I in air by 29.7%, 79.7%, and 53.3% compared with the previous day during hospitalization and on the day of discharge. Conclusion The radiation of external exposure of 131I in the treatment site is low and the shielding is effective. Before ward cleaning, the surface contamination is lower than the required limits except for the toilet. Ventilation is the primary way to reduce the concentration of 131I in air.
  • Original Articles
    Measurement and analysis of dose exposure in childhood intussusception reduction
    ZHANG Baohua, WANG Fei, MIN Nan, LI Zhen, NIU Fei, GAO Zeyu, LIU Wei, YANG Shuhui
    2022, 31(2): 186-191. https://doi.org/10.13491/j.issn.1004-714X.2022.02.010
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    Objective To investigate the dose of radiation in children under going X-ray-guided air enema reduction, and to provide a basis for reducing the risk of radiation injury in pediatric patients.Methods Data were collected from children with intussusception who were treated with air enema. The experimental conditions of high, medium, and low doses of three age groups were analyzed. Phantoms were used to simulate the operation, and the radiation dose was measured using a thermoluminescence system.Results In children with intussusception, the success rate of air enema under the guidance of X-ray was 88% (including secondary intussusception), with anearly re-intussusception rate of 8%. The effective dose of treatment ranged from 0.57 to 12.33 mSv, and the tissues and organs with high absorbed dose were mainly in the chest and abdomen.Conclusion Children in different groups are exposed to significantly differentand relatively high doses. The operators are recommended to use ultrasonic guidance. With X-ray guidance, the exposure time should be minimized and protective equipment for children should be used.
  • Original Articles
    Ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging
    HE Xinyu, PI Yingfei, CAO Xue, WU Yunyun, JIANG Xiaoyan, YUN Mingkai, ZHANG Xiaoli, DING Kuke
    2022, 31(2): 192-196. https://doi.org/10.13491/j.issn.1004-714X.2022.02.011
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    Objective To study the ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging, and to provide data for protection of surrounding people against radiation.Methods A total of 33 patients were selected for 18F-FDG PET/CT myocardial metabolism imaging. Dose equivalent rate was measured at the height of patient chest, in different directions, at different time points and at different distances, to investigate the distribution of ambient radiation of the patient.Results At the same time point and distance, the dose equivalent rates at the left and right sides of the patient were lower than the front and back sides. The dose equivalent rate at 1 m in front of the patient was 13-21 μSv/h after 18F-FDG injection, and decreased to 5-14 μSv/h after PET/CT imaging, with a mean decrease of 46%. The ambient dose equivalent rate decreased exponentially with distance (10~300 cm), and the mean power was -1.2.Conclusion The ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging was high after 18F-FDG injection, and the ambient dose equivalent rate decreased rapidly with time and distance. Our results suggest that patients undergoing myocardial metabolism imaging should avoid prolonged and close contact with other people on the day of examination.
  • Original Articles
    Radioactive concentration of 131I in the air of treatment workplaces for differentiated thyroid cancer with sodium iodide [131I] oral solution
    LIU Ming, GENG Jianhua, ZHENG Rong, LIANG Ying, LI Gaofeng
    2022, 31(2): 197-203. https://doi.org/10.13491/j.issn.1004-714X.2022.02.012
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    Objective To study the radioactive concentration of 131I in the air of workplaces where sodium iodide [131I] oral solution was administrated for patients with differentiated thyroid cancer (DTC) in the Department of Nuclear Medicine, and to estimate the internal radiation dose to the staff. Methods Workplaces of radioiodine 131I therapy for DTC patients in the Department of Nuclear Medicine of a hospital were investigated. Air samples in 131I administration areas and treatment wards were collected respectively and were measured by low-background gamma-ray spectrometry to calculate the activity concentration of 131I in the air and to further estimate the internal radiation dose to staffs. Results The activity concentration in the 131I administration area within the first 3 h of administration was 3～187 Bq/m3. During administration and within the first 3 h of administration, the staff exposed in the administration area for 5～30 min received an internal radiation dose of 0.08～0.50 μSv and 0.00～0.04 μSv, respectively. The highest activity concentration of 131I in the air of the ward was measured on the day of administration, reaching 3091 Bq/m3. After patients were discharged, the activity concentration in the ward gradually decreased to 10～242 Bq/m3 within 48 h. Within 48 h after patients were discharged, the staff exposed in the ward for 5～30 min received an internal radiation dose of 0.01～14.11 μSv. Conclusion A high activity concentration of 131I in the air was recorded during administration for DTC patients in radioiodine 131I therapy, and thus we recommend remote instructed administration or administration through a shielded window. We also recommend that non-treatment related personnel except medical staffs should not enter the ward during patients’ hospitalization at which the activity concentration of 131I in the ward was the highest. After patients were discharged, a delayed entry into the ward is recommended to reduce the internal radiation dose.
  • Original Articles
    Optimization of conditions for preparation of amidoximated polyacrylonitrile membrane for U (VI) adsorption
    CHEN Jiaqi, CHENG Wanting, XU Wenda, LIU Peng, MA Fuqiu, XUE Yun
    2022, 31(2): 204-209. https://doi.org/10.13491/j.issn.1004-714X.2022.02.013
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    Objective To optimize conditions for the preparation of amidoximated polyacrylonitrile (PAO) membrane for U (VI) adsorption that can be easily recycled and reused. Methods Using polyacrylonitrile powder as a raw material, the PAO membrane was prepared using the nonsolvent-induced phase separation method under different conditions. The effects of the polyacrylonitrile concentration and temperature and duration of amidoximation in the preparation of casting solution as well as alkali treatment before adsorption on the U (VI) adsorption performance of PAO membrane were investigated. Results Alkali treatment significantly improved the U (VI) adsorption performance of PAO membrane, and the temperature and duration of alkali treatment affected the U (VI) adsorption capacity. The optimal alkali treatment conditions were 0.1 mol/L NaOH, 80 min, and 60℃. The polyacrylonitrile concentration and temperature and duration of amidoximation in the preparation of casting solution influenced the adsorption performance of PAO membrane. The optimal preparation conditions were 10wt% polyacrylonitrile and amidoximation at 65℃ for 18 h. Under the optimal preparation and alkali treatment conditions, the U (VI) adsorption capacity of PAO membrane reached 255 mg/g. Conclusion The PAO membrane has the advantages of simple preparation, high adsorption capacity, and easy recycling and reuse, which can be used as an ideal material for adsorbing U (VI) in wastewater.
  • Original Articles
    Dosimetry of organs at risk between involved field radiation and extended field radiation in patients with thoracic esophageal cancer
    YUAN Cheng, LIU Mingrui, SHI Linxin, SHAO Weixian, WANG Qiang, DU Aonan, ZHANG Wen, SUN Jianwei, MIAO Hui
    2022, 31(2): 210-213,218. https://doi.org/10.13491/j.issn.1004-714X.2022.02.014
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    Objective To study the irradiation dose of organs at risk (OAR) in involved field radiation and extended field radiation in patients with thoracic esophageal cancer who received intensity modulated radiotherapy (IMRT). Methods A total of 40 patients with thoracic esophageal cancer were treated with IMRT. The involved field, extended field, and OAR were outlined to generate IMRT plans. The conformity index (CI) and homogeneity index (HI) of planning target volume (PTV) and the irradiation parameters of OAR were evaluated for the two plans. Paired t-test was used for comparison of irradiation parameters. Results The PTV of both plans received the prescribed dose. There were no significant differences in CI and HI of PTV between the two groups (P = 0.317, 0.130). There were significant differences in average lung dose, lung V5, lung V20, lung V30, spinal cord Dmean, heart Dmean, heart Dmax, heart V30, heart V40, and heart V60 between the two groups (P < 0.01). Conclusion Compared with the extended field, the involved field can reduce the irradiation dose of ORA in patients with thoracic esophageal cancer, thus reducing the risk of radiation.
  • Original Articles
    Efficacy and safety of iopromideas a contrast agent in gynecological pelvic CT examination
    WEI Ting, WU Yanping
    2022, 31(2): 214-218. https://doi.org/10.13491/j.issn.1004-714X.2022.02.015
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    Objective To investigate the efficacy and safety of iopromide as a contrast agent in gynecological pelvic CT examination.Methods In a retrospective study, 78 patients hospitalized from February 2018 to January 2021 who underwent contrast-enhanced gynecological pelvic CT were involved to investigate the image quality, systemic and local tolerance, and adverse reactions.Results Among the 78 cases, 97.44% had excellent image quality and 97.44% showed tolerance. Mild adverse reactions such as nausea and vomiting, dizziness, headache, local pain, and facial flushing occurred in 8.98% cases. Moderate adverse reactions included severe vomiting with generalized rash (one case) and chest tightness and shortness of breath with generalized rash (one case), and both patients returned to normal after treatment.Conclusion The non-ionic contrast agent iopromide can be used to obtain good image quality in gynecological pelvic CT examination. The incidence of adverse reactions of iopromide is lower than ionic iodine contrast agents, but higher other non-ionic contrast agents.
  • Original Articles
    Clinical application of multi-criteria optimization in radiotherapy for cervical cancer
    WANG Dongdong, LIU Pei, LI Kuo, LI Zhen, ZHU Jianguo
    2022, 31(2): 219-223. https://doi.org/10.13491/j.issn.1004-714X.2022.02.016
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    Objective To investigate the clinical application of multi-criteria optimization (MCO) in radiotherapy for cervical cancer. Methods A retrospective analysis was performed on the clinical data of 15 patients who received radiotherapy for cervical cancer in Shandong Cancer Hospital and Institute. A fixed field intensity-modulated radiotherapy plan was re-optimized using 9 fields on the Halcyon platform, with the goal of achieving a target coverage of > 95% and the lowest dose to organs at risk. The plan was refined until it reached the goal (Plan I) and was calculated using MCO to reach the goal (Plan MI), and the quality assurance verification was performed. The Wilcoxon rank-sum test was used to compare design time, target coverage, radiation dose to organs at risk, and number of monitor units between the plans. Results Both plans met the clinical requirements. There were no significant differences in target dose indices between Plan I and Plan MI (P > 0.05). Plan MI reduced the maximum dose to the small intestine by 0.51 Gy (P < 0.05). There was no significant difference in dose coverage between the bladder and the rectum (P > 0.05). Compared with Plan I, Plan MI saved 34.04 min in design time (P < 0.05). Conclusion MCO can improve the optimization and adjustment, significantly shorten the design time, and improve the efficiency of the plan.
  • Original Articles
    Feasibility of optimizing acquisition time of 18F-FDG PET with BSREM reconstruction algorithm
    ZHANG Tingjie, CHEN Wei, LU Honghui, LIU Ming, XIE Wanming, LIANG Ying
    2022, 31(2): 224-228. https://doi.org/10.13491/j.issn.1004-714X.2022.02.017
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    Objective To compare the impact on 18F fluorodeoxyglucose （18F-FDG） positron emission tomography （PET） image quality when block sequential regularized expectation maximization （BSREM） algorithm and ordered subset expectation maximization （OSEM） algorithm were used at various acquisition times （ATs）, and to discuss the feasibility of AT optimization with BSREM algorithm. Methods In the phantom experiment, the NEMA/IEC PET phantom was adopted. In the clinical study, 66 pulmonary nodules with high uptake values from 61 patients who underwent a 18F-FDG PET-CT examination for pulmonary nodules from March to September 2020 were included. PET images were reconstructed according to BSREM algorithm and OSEM algorithm at various ATs in both the phantom experiment and the clinical study. Coefficient of variation, signal-to-noise ratio, contrast-to-noise ratio, and activity values （uptake value in the phantom experiment; standardized uptake value in the clinical study） were compared between the above sequence images for quality evaluation. Results The phantom experiment showed that the image quality of 120 s BSREM sequence was superior to that of 120 s OSEM sequence, and the image quality of 75 s BSREM sequence was similar to that of 120 s OSEM sequence. The clinical study showed that the image quality of 120 s BSREM sequence was superior to that of 120 s OSEM sequence, and the image quality of 75 s BSREM sequence was slightly better than that of 120 s OSEM sequence. Conclusion In the PET phantom experiment and the clinical study of pulmonary nodules with high uptake values, BSREM algorithm can significantly improve the image quality as compared to OSEM algorithm, and the image quality of 75 s BSREM sequence is slightly better than that of 120 s OSEM sequence.
  • Original Articles
    Establishment and application of normal human brain 18F-FDG PET database with NeuroQ software
    FENG Hongbo, XIE Jinghui, GAO Ya, LI Lei, ZHANG Yanjun
    2022, 31(2): 229-233,238. https://doi.org/10.13491/j.issn.1004-714X.2022.02.018
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    Objective To establish a local human brain 18F-fluorodeoxyglucose positron emission tomography (PET) database with NeuroQ software, and to test its practical value. Methods With NeuroQ software, the PET images of 93 selected subjects were analyzed, and the results were used to create a local normal human database. The metabolism characteristics of the local population were obtained by comparing the original data of the local database with those of the built-in software database, and the difference in case analysis was compared between the two databases. Results Compared with the built-in database, the local database showed the region with high metabolic rate concentrated in the frontal lobe (right superior frontal gyrus: 4.61%, right middle frontal gyrus: 4.49%, left superior frontal gyrus: 3.77%, and left middle frontal gyrus: 3.11%), right posterior cingulate gyrus (6.28%), right inferior parietal lobule (2.46%), left inferior parietal lobule (2.66%), the region with reduced metabolism mainly in the right cerebellum (−3.57%), left cerebellum (−5.27%), and pons (−3.59%). For case analysis, the local database generated results were better consistent with the clinical assessment results of cases. Conclusion Establishment of a local database would eliminate the differences in regions and acquisition conditions, which is of great value to improve the accuracy of diagnosis.
  • Original Articles
    Diagnostic value of echocardiogram and cardiac magnetic resonance imaging for hypertrophic cardiomyopathy
    GUO Guilan, HUANG Heping, LUO Lihong
    2022, 31(2): 234-238. https://doi.org/10.13491/j.issn.1004-714X.2022.02.019
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    Objective To compare echocardiogram and cardiac magnetic resonance imaging (MRI) for diagnosis of hypertrophic cardiomyopathy. Methods A total of 137 patients suspected of hypertrophic cardiomyopathy were recruited. All patients received three-dimensional echocardiogram followed by cardiac MRI, and the detection rate of hypertrophic cardiomyopathy was compared. Results A total of 96 eligible patients with hypertrophic cardiomyopathy were finally enrolledin this study, including 70 males (72.9%) and 26 females (27.1%), with a mean age of 48.2 ±10.2 years. There was a significant difference in the detection rate of hypertrophic cardiomyopathy by echocardiogram (93.8%) and by cardiac MRI (100%) (χ2 = 4.30, P = 0.03). Among the 96 subjects, there was no significant difference in the mean value of maximum left ventricular wall thickness measured by echocardiogram and cardiac MRI (22.1 ±8.9 vs 22.8 ±9.2 mm; t = 1.23, P = 0.32). There was a significant difference in the mean thickness of the basal anterolateral free wall in the left ventricle (18.2 ±7.8 vs 13.9 ±7.1 mm; t = 9.40, P = 0.0007). Conclusion Cardiac MRI scanning is superior to echocardiogram for diagnosis of hypertrophic cardiomyopathy, which may be used as an effective supplement to conventional echocardiogram.
  • Original Articles
    Application of multimedia information technology on precision radiotherapy for patients with head and neck malignant tumors
    HUI Hua, WANG Qiang, CUI Lianhuan, ZHANG Tao, WANG Min, GENG Chong, DU Aonan, SUN Jianwei
    2022, 31(2): 239-244. https://doi.org/10.13491/j.issn.1004-714X.2022.02.020
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    Objective To investigate the effects of multimedia information technologies on precision radiotherapy of head and neck malignant tumors (HNT).Methods A total of 96 patients with HNT recruited from 2016 to 2019 were randomly assignedto group A and group B with the same planning methodand therapists/technicians. Conventional and multimedia information technologies were respectively used in group A and group B for medical science popularization, individualized education, and doctor-patient communication before radiotherapy planning and positioning. Medical compliance, radiotherapy responses, setup errors, and machine occupancy time were investigated.Results Medical compliance was significantly higher (P < 0.05) in group A (96.5%) than in group B (73.8%). Skin acute radiation reaction was significantly lower (P < 0.05) in group A than in group B. Three-dimensional absolute setup errors were 0.69 ±0.29 mm, 0.97 ±0.69 mm, and 0.79 ±0.47 mm in group A, which were significantly lower than 1.39 ±0.81 mm, 1.87 ±1.19 mm, and 2.50 ±0.99 mm in group B(P < 0.05). Traditional three-dimensional setup errors were 0.73 ±0.39 mm, 0.51 ±0.69 mm, and 0.74 ±0.17 mm in group A, which were significantly lower than 1.32 ±0.76 mm, 1.89 ±1.21 mm, and 1.37 ±0.57 mm in group B (P < 0.05). Planning time was 145.15 ±28.45 sin group A, which was significantly lower than 240.38 ±50.45 sin group B (P < 0.05). Positioning time was 115.15 ±18.45 s in group A, which was significantly lower than 173.38 ±24.45 sin group B (P < 0.05).Conclusion The application of multimedia information technologies inmedical science popularization, individualized education, and doctor-patient communication forpatients who received precision radiotherapy for HNT can significantly increase patient compliance, alleviate acute radiation reactions, reduce setup errors, and shorten the machine occupancy time of planning and positioning.
    • Review Articles
  • Review Articles
    Research progress in measurement methods for210Po and 210Pb in environmental samples
    SU Kaijun, WANG Xilong, HUO Menghui, DONG Wei, ZHAI Hezheng, JIAO Ling
    2022, 31(2): 245-249,254. https://doi.org/10.13491/j.issn.1004-714X.2022.02.021
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    210Po and 210Pb exist widely in nature, and they have strong toxicity and strong ionization ability, which can cause continuous harm to human health. Therefore, it is of great significance to determine the activity concentrations of 210Po and 210Pb in environmental samples and to evaluate their harmful effects on human health. This article reviews the research progress in analytical methods and measurement techniques of 210Po and 210Pb in environmental samples.
  • Review Articles
    Research progress of radiation carcinogenic effect and its interference factors for survivors of the atomic bomb disaster in Japan
    JIANG Xia, ZHAN Jingming, WANG Xiuqin, LIU Zhanqi
    2022, 31(2): 250-254. https://doi.org/10.13491/j.issn.1004-714X.2022.02.022
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    Based on the study of solid cancer incidence in survivors of the atomic bomb disaster (atomic bomb survivors) from 1958 to 1998, the Radiation Effects Research Foundation (RERF) performed an additional 11-year follow-up (1999—2009) to further investigate the 50-year solid cancer incidence of atomic bomb survivors from 1958 to 2009. Considering influencing factors such as gender, smoking, drinking, body mass index, and medical exposure, we updated the radiation risk estimate for solid cancer and found a new problem of the relationship between gender-specific dose response, exposure age and cancer incidence during the study, which provides guidance for future research.
    • Expert Comments
  • Expert Comments
    Practical exploration of carrying forward the spirit of scientists in the new era:Taking carrying forward the spirit of “Two Bombs and One Satellite”organized by China Museum of Nuclear Science and Technology as an example
    WANG Maozhi
    2022, 31(2): 255-258. https://doi.org/10.13491/j.issn.1004-714X.2022.02.023
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    Great causes breed great spirits, and great spirits guide great causes. As an embodiment of the spirit of scientists, the spirit of “Two Bombs and One Satellite” contains great spiritual power. This paper introduces some practical exploration of carrying forward the spirit of “Two Bombs and One Satellite”in the new era from the dimensions of psychology and technology, and puts forward some personal thinking and suggestions.