Archive

  • Select all
    |
    Original Articles
  • Original Articles
    Absolute measurement of surface particle emission rates from α and β plane sources using a digitizer
    LU Tianxiang, ZHOU Qianqian, ZHANG Ming, TUO Fei, KONG Shuying
    2023, 32(1): 1-5. https://doi.org/10.13491/j.issn.1004-714X.2023.01.001
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To prove the validity and accuracy of the digitizer instead of the conventional electronics plug-in for radionuclide measurement. Methods Based on a large-area flow-gas multi-wire proportional counter for 2πα and 2πβ surface particle emission rate measurement, the DT5730 digital waveform sampler developed by CAEN was used for waveform signal acquisition, amplitude analysis, and data processing of the α-plane source 241Am and the β-plane source nuclides 14C, 36Cl, and 90Sr-90Y of different energies. Results The deviations between the α and β surface particle emission rate results obtained after dead time and background corrections and the measurements obtained based on the plug-in calibrator were all within 0.6%, within the uncertainty range, under consistent experimental conditions such as electronics threshold and high pressure. Conclusion The digitizer is an effective alternative to conventional electronics plug-ins for α and β signal acquisition and processing and the accurate measurement of α and β emission rates.
  • Original Articles
    Investigation of radioactivity level in an open-pit coal mine in Xinjiang, China and evaluation of personnel exposure dose
    XU Huiping, ZHAO Yang
    2023, 32(1): 6-9,14. https://doi.org/10.13491/j.issn.1004-714X.2023.01.002
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To investigate and analyze the levels of γ dose rate and radon concentration at all sites in a large open-pit coal mine with radioactivity that had been mined for many years in Xinjiang, China, and to estimate the effective dose exposed to the personnel. Methods A portable γ dose-rate instrument FH40G was used for fixed-point monitoring of the mining area, and a continuous radon detector was used for 24 h continuous monitoring of radon concentration level in the site. The personnel exposure dose was estimated according to the measured γ dose rate and radon concentration. Results In this open-pit coal mine, the range of γ dose rate was 51.4-435.8 nGy/h; the mean 24 h radon concentration was 15-25 Bq/m3; the range of annual effective dose to the personnel was 0.29-1.29 mSv/a. Conclusion According to the results of the survey, radon concentration levels at all sites are low, and no remedial action is required. The personnel exposure dose at most of the sites is far below the standard requirements, and some protective measures need to be taken in some areas of the dump.
  • Original Articles
    Analysis of quality control and protection level test results of medical electron linear accelerators in Shanghai, China
    JIANG Zhou, YAO Jie, GAO Linfeng, LU Shunqi, YUAN Weiye
    2023, 32(1): 10-14. https://doi.org/10.13491/j.issn.1004-714X.2023.01.003
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To investigate the quality control and protection level of medical electron linear accelerators in Shanghai, China. Methods The startified random sampling method was used to cover tertiary, secondary and ungraded hospitals, and a total of 30 medical electron linear accelerators in 15 hospitals were tested for quality control and protection level according to relevant standards. Results Five medical electron linear accelerators failed the quality control test, with an overall inspection pass rate of 83.3% and a re-inspection pass rate of 100%. The pass rate of flatness of square X-ray irradiation field (5 cm × 5 cm)-(30 cm × 30 cm) was 83.3%, the pass rate of symmetry of square X-ray irradiation field was 96.7%, and other indices were qualified. All medical electron linear accelerator rooms passed the protection test. Conclusion The protection of medical electron linear accelerator rooms in Shanghai meets the requirements of national standards, and some indices do not meet the requirements of national standards in the preliminary inspection. The quality control of medical electron linear accelerators should be further strengthened to ensure the treatment effect of patients.
  • Original Articles
    Terrestrial gamma radiation level around Shidaowan nuclear power plant, China and influencing factors
    QI Chenyang, ZHANG Wei, ZHANG Xianpeng, LIU Yi, FENG Zhihui
    2023, 32(1): 15-20. https://doi.org/10.13491/j.issn.1004-714X.2023.01.004
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To monitor the cumulative terrestrial γ radiation dose around Shidaowan nuclear power plant, Shandong, China before operation, to analyze the dose levels and influencing factors, and to estimate the annual effective dose to local residents. Methods Fifty-six monitoring sites were selected within 30 km around the nuclear power plant. The environmental γ radiation dose was measured by the thermoluminescence dosimeter monitoring method. The γ radiation dose levels were investigated for 369 days in four monitoring periods (January 16 to April 14, April 15 to July 20, July 21 to October 21, 2021, and October 22, 2021 to January 20, 2022 for periods I to IV, respectively). Relations between γ radiation and monitoring time, altitude, distance from the nuclear power plant were analyzed, and the annual effective dose of terrestrial γ radiation to residents was estimated to reflect the background terrestrial γ radiation level in the area. Results The average values of terrestrial γ radiation dose rate in the four monitoring periods in the area were (76.196 ± 3.366), (81.773 ± 6.144), (93.554 ± 7.449), and (97.604 ± 9.396) nGy/h, respectively, and the terrestrial γ radiation dose rate in the whole year was (87.282 ± 6.589) nGy/h. The effective dose to residents was 0.428 mSv. The terrestrial γ radiation level was high from July 2021 to January 2022. There was no significant difference in the γ radiation dose rate at the monitoring sites with different distance from the nuclear power plant. No impact upon the terrestrial γ radiation dose by the altitude was observed in this study. Conclusion The terrestrial γ radiation level around Shidaowan nuclear power plant in 2021 was at the background level.
  • Original Articles
    Analysis of results of national personal dose monitoring ability assessment in China, 2018—2020
    DONG Qianqian, JIANG Hongmei, ZHANG Xinghui, YE Qianou, ZHANG Ying
    2023, 32(1): 21-25,39. https://doi.org/10.13491/j.issn.1004-714X.2023.01.005
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To determine the effectiveness of quality control measures in the laboratory by participating in the national personal dose monitoring ability assessment, and to improve personal dose monitoring ability and quality. Methods According to the requirements of the National Personal Dose Monitoring Ability Assessment Program and standards, seven groups of personal dosimeter were prepared and irradiated by accurate radiation source as requested, and the dose was measured by the laboratory participating in the assessment. The data were processed, and the uncertainty of the measurement results was evaluated.Results In 2018, the assessment results Hp (10) dose range was 0.68-4.27 mSv, the single group performance deviation was ?0.01 to ?0.06, and the comprehensive performance deviation was 0.04, and the result was qualified. In 2019, the assessment results Hp (10) dose range was 0.74-8.06 mSv, the single group performance deviation was 0.00 to ?0.08, and the comprehensive performance deviation was 0.04, and the result was qualified. In 2020, the assessment results Hp(10) dose range was 0.83-3.93 mSv, the single group performance deviation was ?0.01 to ?0.10, and the comprehensive performance deviation was 0.06, and the result was excellent. Conclusion The personal dose monitoring system in our laboratory runs smoothly, and the monitoring results are accurate and reliable. The laboratory can issue test reports that meet the requirements of national standards.
  • Original Articles
    Investigation and analysis of indoor radon concentration of urban residents in Shiyan, China
    LI Pei, ZHOU Wenshan, WANG Fang, GUO Liangliang, YANG Shaohua, ZHAO Tongqiang, WU Jiabing, SUN Rongbin
    2023, 32(1): 26-29. https://doi.org/10.13491/j.issn.1004-714X.2023.01.006
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To monitor the indoor radon concentration of urban residents in Shiyan, China, and to analyze the related influencing factors. Methods From April to July, 2019, RSKS standard detectors were used to measure the indoor radon concentration of 125 households in Shiyan, and the results were analyzed. Results The indoor radon concentration of residents in Shiyan showed a skewed distribution, ranging from 13.8 to 145 Bq/m3, and M (P25,P75) was 38.3 (29.0,62.0) Bq/m3. The estimated annual effective dose of radon and radon daughters from inhalation was 0.52-5.50 mSv, and M (P25,P75) was 1.45 (1.10, 2.36) mSv, which was consistent with literature. Building structure (H = 14.10, P < 0.001), floor (H = 24.41, P < 0.001), and geographical region (H = 8.963, P < 0.05) were influencing factors of indoor radon concentration, and the differences were significant. Conclusion The indoor radon concentration of urban residents in Shiyan is lower than the national standard limit. However, in daily life, it is still necessary to take appropriate measures to reduce the concentration of indoor radon as much as possible.
  • Original Articles
    An analysis of occupational health examination results of 450 radiation workers in a steel mill
    HOU Jianwu, ZHANG Youzhong, MAO Xuesong, HOU Dianjun, MA Ya
    2023, 32(1): 30-34. https://doi.org/10.13491/j.issn.1004-714X.2023.01.007
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To investigate the occupational health status of 450 radiation workers in a steel mill when they resigned, and to provide references and suggestions for the occupational health monitoring of the enterprise employees and for the workers’ proper arrangement after their resignations.Methods Occupational health examinations were performedon 450 steel workers who were about to resign in accordance with the applicable laws and regulations. And the examination results were statistically analyzed. Results Among the 450 radiation workers, 82% had abnormal examination results which included chromosome aberration in peripheral blood lymphocytes (4.89%), lens opacity (44.44%), pinguecula (25.33%), hypertension (28.22%), thyroid dysfunction (9.59%), and abnormal liver ultrasound findings (30.89%). Compared with the normal population, these steel workers had a significantly higher chromosome aberration rate in peripheral blood lymphocytes and a significantly higher incidence rate of ocular disorders. Conclusion It is important to effectively manage the occupational health of radiation employees in steel mills, and to regularly provide training on occupational health protection. To avoid radiation damage, workers should pay close attention to radiation protection at work, especially eye protection, to avoid eye disorders.
  • Original Articles
    Influence of 4D CT-based respiratory signal acquisition methods on delineation of moving tumor targets
    LIU Qianqian, YAO Shengyu, CHEN Xuming, HOU Lingtong, HU Zhekai
    2023, 32(1): 35-39. https://doi.org/10.13491/j.issn.1004-714X.2023.01.008
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To compare the effects of different respiratory signal acquisition methods on the delineation of moving tumor targets. Methods A cube phantom containing a sphere was placed on a motion platform to simulate respiratory movement by setting motion period, frequency, and direction. Respiratory signal was acquired by real-time position management (RPM) method and GE method independently. Target delineation was conducted using the maximum intensity projection (MIP) sequence. The difference between the reconstructed volume and the theoretical moving volume was compared under the two respiratory signal acquisition methods for cube and sphere targets. Results Under the same respiratory signal acquisition method, the same respiratory amplitude, and different respiratory frequencies, reconstructed volume changes were relatively small. For the sphere target, the deviation between the reconstructed volume and the theoretical moving volume was −1.5% to 5.7% with the RPM method and −1.3% to −13.8% with the GE method (both P < 0.05). For the cube target, the deviation between the reconstructed volume and the theoretical moving volume was 0.2% to 0.9% with the RPM method and −2.6% to 0.9% with the GE method, with no statistical significance. Conclusion For small-volume sphere targets, the target volumes obtained from MIP images by the two respiratory signal acquisition methods are both smaller than the actual moving volume. For large-volume cube targets, there is no significant difference between the reconstructed and theoretical results with any respiratory signal acquisition method. The RPM method produces smaller deviation and better image quality when reconstructing small-volume targets.
  • Original Articles
    Clinical application of optical surface monitoring system in radiotherapy after radical mastectomy for left breast cancer
    KUANG Bei, LIU Zhongqiang, WANG Hui, WU Zhenming, YE Xiqu, LIN Gengxian
    2023, 32(1): 40-45. https://doi.org/10.13491/j.issn.1004-714X.2023.01.009
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To study the setup error under deep inspiration breath hold (DIBH) guided by optical surface monitoring system (OSMS) and free breathing (FB) FB1 and FB2 (without OSMS guidance, directly set up the body marker line by laser lamp) in radiotherapy after radical mastectomy for left breast cancer, and to provide a basis for individualized clinical target volume-planning target volume (CTV-PTV) expansion for the doctor in charge to delineate the target volume. Methods A total of 36 patients with left breast cancer after radical mastectomy were selected and divided into three groups, in which cone beam computed tomography (CBCT) images were taken in three states: DIBH, FB1, and FB2, respectively. CBCT and CT images were analyzed for registration; the absolute error data of linear displacement in the ventro-dorsal, cranio-caudal, and left-right directions were recorded, and the expanding margin was calculated. Results The translation errors in the ventro-dorsal, cranio-caudal, and left-right directions were (0.06 ± 0.22) cm, (0.05 ± 0.23) cm, and (0.01 ± 0.24) cm in the DIBH group, (0.07 ± 0.21) cm, (0.02 ± 0.23) cm, and (0.02 ± 0.21) cm in the FB1 group, and (0.07 ± 0.24) cm, (0.07 ± 0.34) cm, and (0.25 ± 0.09) cm in the FB2 group. The statistical results of the DIBH group and FB1 group in the ventro-dorsal, RTN, and ROLL directions were significantly different (P < 0.05). The statistical results of the FB1 group and FB2 group in the ventro-dorsal direction were significantly different. The relation of three groups in the value of margin of planning target volume was DIBH < FB1 < FB2 in the ventro-dorsal and cranio-caudal directions and FB1 < DIBH < FB2 in the left-right direction. Conclusion OSMS-guided DIBH radiotherapy in patients with left breast cancer after radical mastectomy can reduce the setup error and provide an important basis for individualized CTV-PTV expansion for the doctor in charge to delineate the target volume.
  • Original Articles
    Outcomes and prognostic factors of differentiated thyroid cancer with bone metastasis
    WANG Yan, ZHENG Rong, FAN Rong, LIN Lin, GENG Jianhua
    2023, 32(1): 46-51,61. https://doi.org/10.13491/j.issn.1004-714X.2023.01.010
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To investigate the outcomes and prognostic factors of differentiated thyroid cancer (DTC) with bone metastasis.Methods A retrospective study was conducted on 108 DTC patients with bone metastasis who were treated in the Cancer Hospital of Chinese Academy of Medical Sciences. Kaplan-Meier survival curves were generated. Log-rank test and Cox proportional hazards model were used to screen the prognostic factors. The correlation between treatment and prognosis was analyzed. Results The median overall survival was 70 months. The 5-, 10-, 15-, and 20-year overall survival rates were 54.4%, 24.3%, 9.8%, and 4.3%, respectively. Univariate analysis showed improved prognosis in patients with single bone metastasis, without skeletal-relatedevents (SREs), and without cervical lymph node metastasis (P = 0.003-0.019). Patients who received combined treatments (P < 0.001) or 131I treatment alone (P = 0.109) showed better prognosis than those without 131I treatment. Multivariate analysis identified single bone metastases, SREs, and treatmentas independent prognostic factors.Conclusion In DTC patients with bone metastasis, good prognosis is significantly associated with single bone metastases, absence of SREs, and 131I therapy in combination with other therapeutic approaches.
  • Original Articles
    Effects of X-ray volume imaging registration methods on position verification for radiotherapy in treatment of middle/lower-segment esophageal cancer
    LIU Haojia, WANG Huitao, XU Hongwei, ZHENG Anping, SUN Xiaodong, ZHU Jinfeng
    2023, 32(1): 52-57. https://doi.org/10.13491/j.issn.1004-714X.2023.01.011
    Download PDF ( ) HTML   Knowledge map   Save
    Objective To compare the set up errors derived from different registration methods of the X-ray volume imaging (XVI) system for radiotherapy in the treatment of middle/lower-segment esophageal cancer, and to provide a reference for radiation treatment of esophageal cancer. Methods We randomly selected 63 patients with middle/lower-segment esophageal cancer, and obtained their reconstructed XVI images at the first therapy to perform automatic registration with gray-value and bone registration methods. We acquired and compared the three translation errors (along x [left to right], y [head to feet], and z [front to back] axes) and three rotation errors (around the x, y, and z axes) derived from the two registration methods. Results Gray-value registration had significantly smaller translation errors along the x and z axes than bone registration (x azes t = −2.78, z azes t = −2.15, P < 0.05), but there was no significant difference along the y axes (P > 0.05). The rotation errors around the three axes were all smaller than 1°, and were smaller with gray-value registration than with bone registration, but without significant differences (P > 0.05). Conclusion We recommend gray-value registration for radiotherapy in the treatment of middle/lower-segment esophageal cancer. Manual verification or fine-tuning is recommended after automatic registration in clinical practice. Besides translation errors, rotation errors should also be paid attention to.
    • Review Articles
  • Review Articles
    Latest development of operational quantities and their impact
    LIU Lantao, WEI Kedao
    2023, 32(1): 58-61. https://doi.org/10.13491/j.issn.1004-714X.2023.01.012
    Download PDF ( ) HTML   Knowledge map   Save
    With the utilization of more types of radiation with a wider energy range, the application scope of the currently valid operational quantities is limited due to some conceptual defects, so a new group of operational quantities was proposed recently by the International Commission on Radiation Units and Measurements. The unification of protection quantities and operational ones is achieved in conceptual and physical sense. However, to achieve the comprehensive application of these new operational quantities in China, such preliminary work should be done as computational model construction and built-in of a calibration system in monitoring equipment, which depends on the collaborative development of multi-parties.
  • Review Articles
    Research progress of imaging flow cytometry in automatic analysis of radiation biodosimetric indicators
    LIU Xiaoming, CHENG Jiao, CUI Shuangshuang, DANG Xuhong, DONG Juancong
    2023, 32(1): 62-65. https://doi.org/10.13491/j.issn.1004-714X.2023.01.013
    Download PDF ( ) HTML   Knowledge map   Save
    A large number of people would be exposed to irradiation in large-scale nuclear and radiation accidents or nuclear terrorist attacks. Therefore, it is urgent to establish rapid and high-throughput biodosimetry for in triage, providing a basis for emergency management. Imaging flow cytometry (IFC) possesses the high through put advantages of traditional flow cytometry and the sensitivity and specificity of microscope, and has a good application prospect in the research and development of rapid, automated, and high-throughput biological dose estimation technology. This article reviews the application progress of IFC in biodosimetry, and provides a reference for the development of biological dose estimation and detection equipment for large-scale nuclear and radiation accidents.
  • Review Articles
    Progress in application of positron emission tomography/computed tomography (PET/CT) imaging in tumor screening
    LU Xiaoqian, ZONG Lingyan, SHEN Qi
    2023, 32(1): 66-69,74. https://doi.org/10.13491/j.issn.1004-714X.2023.01.014
    Download PDF ( ) HTML   Knowledge map   Save
    Worldwide, the incidence of cancer is greatest in China. Tumor screening is effective to achieve early diagnosis, improve prognosis, increase the quality of life, and reduce mortality among cancer patients. Positron emission tomography/computed tomography (PET/CT) imaging provides metabolic data to support initial staging, treatment planning, and response evaluation in tumor screening, as well as tumor follow-up. The progressive integration of PET/CT imaging in radiotherapy has its basic principle in the biological heterogeneity of inter- and intra-tumor malignant lesions, and the radiation dose is required to be adjusted to achieve effective local tumor control among cancer patients. In addition, PET/CT imaging provides data on the biological features of tumor lesions, such as metabolism, hypoxia, and proliferation, which is useful to identify radiation-resistant regions and optimize treatment plans. These data are effective to reduce the uncertainty and variability in the anatomic description of tumor sites. This review summarizes the application of PET/CT imaging in common tumors.
  • Review Articles
    Advances in multimodal MRI-based study of brain networks in patients with carotid artery stenosis
    GONG Wenru, LV Wencheng, CUI Yi
    2023, 32(1): 70-74. https://doi.org/10.13491/j.issn.1004-714X.2023.01.015
    Download PDF ( ) HTML   Knowledge map   Save
    Stenosis and occlusion caused by carotid atherosclerosis is an important cause of ischemic stroke. In recent years, with the continuous development of magnetic resonance imaging (MRI) technology and the introduction of complex network theory, brain network analysis can be used not only to explain the clinical symptoms and cognitive dysfunction in patients with carotid stenosis caused by changes in network topological properties of different brain regions, but also to explore the imaging markers of carotid stenosis, thus providing important reference data for the diagnosis of early asymptomatic carotid stenosis, the selection of individualized intervention programs, and the assessment of efficacy. Brain network analysis has been used as a powerful tool. In this paper, we review the studies of structural and functional brain networks in patients with carotid stenosis, and introduce the definitions of brain network nodes and edges and important topological properties of complex networks. We also analyze the current research on brain network in patients with carotid stenosis, and discuss the challenges and outlook of existing imaging techniques and network construction methodologies in this field.
  • Review Articles
    Advances in the diagnosis of primary solid small bowel tumors by contrast-enhanced multislice spiral CT
    CHEN Yingxiu, LIU Qianqian, JI Huijun, CHEN Qi, GU Mengyao, LI Wanhu
    2023, 32(1): 75-80. https://doi.org/10.13491/j.issn.1004-714X.2023.01.016
    Download PDF ( ) HTML   Knowledge map   Save
    Primary small bowel tumors have low incidence and contain predominantly solid components, and the lesions are similar and difficult to be detected and distinguished with multislice spiral CT (MSCT) plain scans. In this article we describe contrast-enhanced MSCT technique and imaging characteristics for solid small bowel tumors or small bowel tumors containing predominantly solid components, including the type and use of contrast agents. In contrast-enhanced MSCT, small bowel imaging with CT has the advantages of determining the true extent of intestinal wall lesions, the possible extent of wall penetration, the degree of mesenteric involvement, and distant metastases, as well as easiness to detect and identify the blood supply vessels of small bowel tumors and assessment of the corresponding complications. Contrast-enhanced MSCT has become the best noninvasive imaging technique for the diagnosis, evaluation, and staging of solid small bowel tumors or small bowel tumors containing predominantly solid components. CT texture analysis (CTTA) is a new research hotspot and can be useful for the correct diagnosis of primary small bowel tumors containing predominantly solid components.
  • Review Articles
    Application progress of SlowflowHD in prenatal ultrasound screening
    PENG Yujie, KONG Qingfeng
    2023, 32(1): 81-86. https://doi.org/10.13491/j.issn.1004-714X.2023.01.017
    Download PDF ( ) HTML   Knowledge map   Save
    Prenatal ultrasound screening is an important means to exclude fetal structural abnormalities. With the continuous development of technology, more vascular abnormalities can be found more early, which improves the quality of the social population. Traditional Doppler ultrasonic images have a low resolution and poorly display small blood vessels. SlowflowHD is a particularly sensitive power Doppler designed to detect small microvessels with a low flow rate, and can improve the resolution of fine blood vessels. SlowflowHD has been gradually applied to prenatal screening because of its unique characteristics such as high display frame rate, high line density (high resolution), and good sensitivity. This article aims to explore the clinical application progress of SlowflowHD in prenatal screening.
    • Expert Comments
  • Expert Comments
    How much exposure dose does a patient receive in PET/CT examination?
    GENG Jianhua, LIU Jianing
    2023, 32(1): 87-91. https://doi.org/10.13491/j.issn.1004-714X.2023.01.018
    Download PDF ( ) HTML   Knowledge map   Save
    Positron emission tomography/computed tomography (PET/CT) scanner is an irreplaceable instrument in clinical diagnosis. The exposure dose that a patient receives is the sum of the doses caused by PET and CT examination. This study discussed the exposure dose level that a patient received during PET/CT examination according to the research data. Like other radiological diagnostic methods, PET/CT examination brings benefits outweighing its radiation risk. It is not advisable to exaggerate or ignore the exposure dose. The patient’s exposure dose caused by PET/CT examination should be controlled as much as possible under the premise of meeting clinical needs.