目的:分析全国放射诊断资源分布的基本情况，为进一步优化放射诊断资源配置，改进放射诊断放射防护薄弱点提供数据支持。方法:根据2017—2019年发布的全国医用辐射防护监测方案的统一方案和调查表开展调查，调查对象包括全国所有开展放射诊断医疗机构；放射诊断调查指标包括放射诊断医疗机构分布、各类设备数量、放射工作人员的数量等信息、放射防护用品配备情况以及放射诊断频度等信息；调查方法为问卷调查，并通过全国医用辐射防护监测信息系统上报。按照组织机构代码，机构名称排除重复上报的机构。原始数据从数据库导出为Excel表格形式，进行统计分析。结果:截至2019年年底，除新疆生产建设兵团及港澳台地区和军队系统外，全国共有放射诊断医疗机构68 924家；放射诊断设备总数为147 913台；放射诊断防护用品全国配备率为91.7%。全国共有从事放射诊断的工作人员367 201人，占全部医疗机构放射工作人员406 830人的76.1%。放射防护用品总体配备率较高，但一级医院的防护用品配备率在各级别医院中最低。防护用品配备按医院级别依次提高。按经济发展水平分布看，防护用品配备东部地区最高，中部和东北地区最低，两个地区基本在90%左右。结论:本次3年一轮的全国放射防护监测调查基本掌握了放射诊断及其防护情况的现状，积累了大量的调查数据，为国家及各省制定相关防护政策及标准制定提供数据支持。通过调查数据统计汇总，全国仍有近千台直接荧光屏透视机在用，应建立相关政策和标准逐渐淘汰此类辐射危害严重的设备。

Objective To construct a national radiological health information platform, in order to collect and analyze radiological health monitoring and survey data, so as to improve data utilization and ensuring technology support to radiological health. Methods In accordance with China′s relevant laws, regulations and regulations, a national radiological health information platform was designed, developed and operated in response to the needs of radiological health monitoring, scientific research and management. Results The system was initially established in 2015, consisting of five business modules: medical radiation protection, personal dose, occupational health, food radioactivity monitoring and occupational radiological disease reporting. In the past 4 years, the system has been running normally and 5 business databases have been established. More than 8 million data of monitoring and survey have been collected. More than 1400 terminal users have good experiences and frequent interactions. Conclusions The successful construction of the national radiological health information platform not only promotes and standardizes the network direct reporting of radiological health monitoring and investigation business data, but also provides analytical and utilization tools for technical institutions/ personnel on radiological health, and gradually becomes an important scientific basis and database for the development of radiological health laws, regulations and standards in China as well as for national health service.

Objective To construct a national medical radiation protection monitoring information system (NMRPMIS) based on the national radiation health information platform, support the national medical radiation protection monitoring project data reporting, and comprehensively understand the current situation of medical radiation protection. Methods According to the national radiation protection monitoring plan, laws, regulations and standards, HTML, CSS and JavaScript were used in the front end, JAVA language was used in the back end, SQL server was used in the platform database and Tomcat was used as the middleware. A data reporting and analysis system was set in the system through B/ S structure, with statistical analysis of the 2017 annual monitoring data carried out. Results The business composition of the platform includes four levels: data acquisition ( through various business systems), data resource integration (integration of business system public data), application, and display. The national medical radiation protection monitoring system with flexible structure, centralized information and convenient operation was implemented. The national medical radiation protection information was reported in 2017. The basic situation of radiation protection in 33565 hospitals and the performance and protection information of 10624 pieces of radiation diagnosis and treatment equipment were reported in 2017. A total of 95 statistical information reports were completed, describing the current situation of medical radiation protection in China from four dimensions: time, administrative geographic information, hospital level, and equipment types. Conclusions Medical radiation protection monitoring system helped achieve the design goal and successfully complete the data reporting in 2017. It provides data support for understanding the current situation of medical radiation protection and the protection management policymaking in China.

Objective To analyze 20 indicators for the evaluation of medical radiation protection monitoring in 31 provinces,municipalities or autonomous regions in 2017 and provide technical support and reference for further optimization of medical radiation protection monitoring projects.Methods According to " medical radiation protection monitoring assessment score sheet for medical and health institutions",a full range of analysis and evaluation was carried out of medical radiation protection monitoring and implementation at nationwide medical and health institutions by using fuzzy combined method of TOPSIS and rank sum ratio.Results TOPSIS method and rank sum ratio weighted fuzzy joint analysis showed that the top three indicators,in descending order,were management of provincial implementation plans,management of project leaders in various cities and management of funds whereas the lowest three indicators were completion of radiotherapy equipment commissioning,innovation and highlights and tcoverage of radiotherapy equipment.Conclusions The fuzzy combined application of TOPSIS method and rank sum ratio method can provide the comprehensive quantitative result for the implementation of medical radiation protection monitoring in 2017,objectively evaluate the implementation of various indicators,summarize the highlights and bottlenecks of work in 2017,and provide technical support and reference for further optimization of medical radiation protection monitoring.

目的 分析2015-2017年我国部分放射诊疗机构放射工作人员的职业健康监测数据,为职业性放射性疾病的预防和控制提供科学依据.方法 通过“全国放射卫生信息平台-职业健康监测模块”采集近三年部分放射诊疗机构放射工作人员职业健康监测相关数据,并进行统计与分析.结果 2015-2017年监测医院放射工作人员个人剂量监测率分别为98.3％、98.9％、98.7％;职业健康检查率分别是95.5％、94.8％、95.7％.外周血淋巴细胞染色体畸变异常人员比例逐年降低分别为:0.9％、0.7％、0.3％;眼晶状体混浊率逐年降低分别为8.6％、7.7％、7.9％;甲状腺检查异常率逐年增加分别为18.8％、21.1％、22.1％.结论 总体上,我国放射诊疗机构放射工作人员的职业健康监护水平逐年提高,但眼晶状体和甲状腺的检查和防护仍需高度关注.

Objective To understand and analyze the individual dose level of occupational exposure of medical radiation workers in China in 2015,and to provide the data and scientific basis for the prevention and control of occupational radioactive disease.Methods By using the "Occupational health of Radiation workers management system-external exposure of personal monitoring",the individual dose monitoring results and other related data of medical workers were collected and analyzed statistically.Results Altogether,data for 214,860 persons have been collected in 2015.The average annual individual effective dose was 0.429 mSv.The average annual individual dose of diagnostic radiology,dental radiology,nuclear medicine,radiotherapy,interventional radiology and others,six categories of occupational groups were 0.423 mSv,0.326 mSy,0.538mSv,0.321 mSv,0.542 mSv and 0.407 mSv,respectively.The difference of average annual individual effective dose of six categories of occupational groups was statistically significant (P ＜ 0.001).The average annual individual dose of nuclear medicine and interventional radiology were significantly higher than those of other occupational categories (P ＜ 0.05).Conclusion The average annual individual effective dose of radiation workers meets the national standards.The exposure dose of nuclear medicine and interventional radiation workers is relatively high.To protect their occupational health,the relevant radiation protection measures and facilities should be strengthened.

Objective:It is to discuss results and significance of PET/CT in the performance tests.Methods: According to NEMA NU 2-2007 Performance Measurements of Positron Emission Tomographs and GB 17589-2011 specifications for quality assurance test for computed tomography X-ray scanners standards, with phantoms of nuclear medicine and CT, performance testing was done.Results: Spatial Resolution (FWHM): transverse 1 cm 4.16 mm, axial: 1 cm 4.04 mm, transverse 10 cm 4.92 mm, axial: 10 cm 5.74 mm. Sensitivity: 9.6 s-1·kBq-1, scatter fraction: 35.4%, peak NEC rate: 1.69×105 s-1.Conclusion: According to manufacturers and national standards, the results of performances testing are up to standard. It is necessary to enhance the effect of in quality control(QC) of PET/CT and the fundamentality of the performance tests, so that the devices come to the demands for clinical practice.

Objective To study the variation of radon emanation coefficient of aerated concrete blocks with respect to moisture content, temperature and relative humidity.Methods By using continuous radon measurement instrument and sealed cavity, the radon emanation coefficients were obtained in conditions of different moisture (0-60％), temperature (10-40℃) and humidity (12％-95％).The variation of radon emanation coefficients (ε) with respect to noisture (s) , temperature (T) and hunidity were also studied by regression analysis.Results The study showed a logarithmic increase in radon emanation coefficient with the increased moisture [ε =0.096·ln(s +2.43) +0.03 ,R2 =0.952] , a linear increase with increased temperature (ε =0.002 45 · T + 0.060 1 , R2 =0.987) , and no significant influence on radon emanation coefficient with respect to humidity (P ＞ 0.05).Conclusions Both moisture and temperature affect the radon emanation coefficient to a larger extent.Attention should be paid to both factors in the assessment and control system of radioactive hazard from building materials.

Objective: By determining the actual dose of the workers who in charge of radionuclide loading and injection in clinical PET Department, and analyzing the results to find the effective protection measures and reasonable methods. Methods: Objective the personal dose equivalent by the ring–type TLD dose-meter and chest badge-type TLD dosemeter. The results were analyzed to find the reasons of differences. Results: Injecting for one patient, the first worker’s chest dose equivalent of A hospital the is about: 1.3×10-3 mSv, left hand is 0.107 mSv, right hand is 0.113 mSv. The second worker’s chest dose equivalent of A hospital is about: 1.6×10-3 mSv, left hand is 0.132 mSv, right hand is 0.200 mSv; on the other hand, Injecting for one patient the worker’s chest dose equivalent in B hospital is much less than the minimum detection level, left hand is 0.0146 mSv, right hand is 0.0070 mSv. Conclusion: By optimizing work procedures and adopting effective protection measures can get a good protection effect of 18F radionuclide.

Increased frequency of micronuclei is positively correlated with the molecular dosimetry of genotoxic damages. The cytokinesis-block micronucleus test (CBMN test) is a well-established assay used in toxicological screening for potential genotoxic compounds. Since the method is simple and economical, CBMN assay can be employed on a large scale as a quantitative biological dosimeter. Automated detection of binucleated cells and micronuclei helps to increase the speed and reproducibility of CBMN method and is very beneficial for large-scale biomonitoring applications. Fuzzy c-means algorithm as well as mathematical morphology was employed in this preliminary study to identify the interested structures and helped to develop a robust comprehensive program to analyze the CBMN slides automatically. As a result, all the three kinds of binucleated cells with different nuclear morphologies were identified by our program. The structures that did not satisfied the criteria of binucleated cells and micronuclei were successfully excluded by the program.

Objective:To discuss results and significance of SPECT planar intrinsic performances in the test.Methods:According to NEMA standard,with phantom of nuclear medicine,performance testing was done as to intrinsic integral uniformity,intrinsic spatial resolution,intrinsic linearity,intrinsic count rate performance.Results:For firstly testing more than 40 SPECT planar,intrinsic integral and intrinsic spatial resolution were up to standard,but the unqualified rates of intrinsic integral and intrinsic linearity were 19% and 24%.Conclusion:It is necessary to enhance the effect of in quality control(QC) of SPECT planar and the fundamentality of the performance test,so that the devices can meet the demands for clinical practice.

2002年我国引进了第1台正电子发射断层成像/断层成像(PET/CT)设备,其后购买的PET设备基本都带有CT功能.现有的PET设备80%以上为PET/CT,不带CT的PET正逐步被淘汰。

Objective To identify the steps with potentially higher risk through the analysis of human factors in clinical PET application so as to provide the efficient measures to reduce the risk of potential exposures.Methods The basic data were obtained through field investigation, questionnaire,failure mode, risk identification, FMECA and expert's evaluation, with statistical analysis made.Comparison was made of the relative risk values of automatic encapsulation equipment and manual encapsulation ones.Results The 10 steps with potentially higher risks were identified through analyzing human factors of clinical PET application, of which 8 occurred in the phase of chemical synthesis.The measures to control risk were addressed for the steps with higher risk.The results show that the relative risk value of the clinical process with automatic encapsulation equipment was 2.28 ± 0.99 and the one with manual encapsulation equipment was 3.20 ± 2.01 ( t = 2.56, P ＜ 0.05 ), with the latter being 76% of the former.Conclusions Failure mode and FMECA are effective in risk evaluation of clinical PET application, which can provide important basis for risk control.

近年来,正电子发射断层设备PET(包括专用PET和PET/CT)的应用不断发展,截至2010年7月,PET/CT国内总数达到133台[1].专用PET和PET/CT机型主要为美国GE公司的Discovery型号,德国Siemens公司的Biograph型号和荷兰Philips公司的Gemini GXL型号.

>据不完全统计,我国目前有100多台的PET和PET/CT,但大多没有经过性能测试。这主要的原因是缺乏统一的国家标准。国际上有两种标准,一是IEC(国际电工委员会)发布的,二是NEMA(美国国家电器制造商协会)发布的[1-2]。

Respiratory motion identification and corrections for the motion artifacts in SPECT imaging were analyzed in a phantom study by identifying,the blur direction in the SPECT image through a directional derivative analysis of the motion blurred image.The blur extent was estimated by an auto-correlation analysis of the pseudo-whitened blurred image.Then,a Wiener filter and the Richardson-Lucy blind deconvolution algorithm(RL) were employed to restore the motion blurred image according to the estimated point spread function.The results show that the identification results for 5 typical simulated motions are very close to the true value and that the RL algorithm enables better motion artifact correction within 5 iterations than the Wiener filter.This method can be used to identify respiratory motion with a post-reconstruction based deconvolution algorithm as a promising method in clinical practice to correct motion artifacts in SPECT/PET images.

正电子发射断层设备(positron emission tomography,PET)技术发展很快,特别是各种新晶体的应用有效地提高了PET设备的性能.在常用的3种晶体BGO、LSO和GSO中,LSO因其余辉时间短和死时间小,使其在高计数和快速扫描方面更具优越性。

The standard activity meter with 4πγionizing chamber (the uncertaintyδ≤5%) is used to verify the medical activity meters of user in order to evaluate the accuracy of radionuclide activity.The results show that 20 verified activity meters which have 2 not qualified within 10% of the tolal units.Therefore the medical activity meters in use should be verify at regular intervals to send the PSML or SSDL.This is an important job for quality assurance in the nuclear medicine and patient radiation protection.

According to the NEMA NU2-2001《Performance Measurements of Positron Emission Tomography》to measure the performance of PET/CT,report the results including spatial resolution,scatter fraction,count losses,and randoms measurement,accuracy: corrections for count losses and randoms,sensitivity,image quality,accuracy of attenuation and scatter corrections.The image quality by using 3D acquisitions mode is better than that by using 2D acquisitions mode.

PET/CT是把PET与CT两种影像技术有机结合在一起的新技术。PET是功能显像技术,它能诊断出早期肿瘤的细微病变,但对病变区的生理解剖位置和病变区的形状诊断不够精确。CT是解剖显像技术,它能诊断出肿瘤病变区的精确解剖位置和形状,但不能诊断出组织的早期病变和细微病