儿童CT扫描辐射剂量现状调查和诊断参考水平的初步探讨

目的通过对全国范围内儿童CT辐射剂量的调查, 了解儿童CT辐射剂量的现状, 探讨儿童CT辐射剂量的诊断参考水平(DRL)。方法以2021年11月30日为起点, 按时间倒叙回顾性收集全国儿科CT检查的辐射剂量报告。将所有CT扫描分为0～1个月、>1个月～4岁、>4～10岁、>10～14岁、>14～18岁5个年龄段;头颅平扫、鼻窦平扫、颞部平扫、颈部平扫、胸部平扫、腹部平扫、头颅增强、胸部增强、腹部增强9个检查项目。记录每次CT扫描的容积CT剂量指数(CTDIvol)和剂量长度乘积(DLP), 其75%位数为DRL。将本次调查中头部平扫、胸部平扫、腹部平扫的DRL与我国专家共识和欧洲DRL指南进行比较。结果共收集到2019年3月至2021年11月间全国23个省、自治区、直辖市的33家医院, 包括20家儿童专科医院、11家妇女儿童医院、2家综合医院的儿童CT检查19 135次, 获得了5个年龄段、9个检查项目的45个亚组的CT辐射剂量DRL。本调查DRL结果显示, 5个年龄组头颅平扫的CTDIvol为26.9～42.8 mGy, DLP为347～694 mGy·cm;...     

病人术中剂量参考标准:多中心研究

正目的根据2013/59/Euratom欧洲指南要求,评估最常用手术程序中的剂量参考标准(DRL)。方法由6个中心共同研究。分析了8种骨科、泌尿外科和胃肠外科手术。于     

我国CT检查成年人辐射剂量诊断参考水平的建立历程及解读

经过放射诊断专家、影像技术专家、辐射防护专家和专业技术人员10多年的探索,一项基于大规模国内调查数据而建立的CT检查成年人辐射剂量诊断参考水平(diagnostic reference level,DRL)以国家卫生行业标准(WS/T 637-2018)形式发布。其制定原则和方法符合国际惯例和我国的实际情况,基本上涵盖了我国成年人常见CT检查项目,与国外的DRL比较,整体处于一个合理或较低的剂量水平。给出的50%分位数(可能达到水平)和25%分位数(异常低剂量的提示水平)作为辐射剂量优化指导的额外工具。在日常放射诊断活动中,使辐射剂量与图像质量、临床诊断任务相匹配,降低非正当过高或过低剂量的发生频率。     

成年人CT扫描中辐射剂量和诊断参考水平的探讨

目的 通过全国范围内CT辐射剂量的调查,了解成年人辐射剂量的现状,进而探讨成年人CT的诊断参考水平不符,需要根据我国的实际建立自己的DRL。方法 2015年9月至2016年3月在全国30个省、自治区、直辖市调查168家医院,其中三级和二级医院各约占一半。随机调查年度状态检测合格的168台CT,包括了临床应用中普遍使用的品牌和型号。每台CT收集头颅、鼻窦、颈部、胸部、腹部、盆腔、腰椎、尿路造影、冠状动脉CT血管造影（CTA）、颅脑CTA、颈部CTA和胸腹CTA共12个检查项目、每个项目10个随机病例。以容积CT剂量指数（CTDI_vol）和剂量长度乘积（DLP）作为剂量参量,每个检查项目的所有数据按照大小排序,取25%、50%和75%位数,其中75%位数为参考水平。所得剂量数值与国际相关放射防护组织发布的DRL进行比较。结果 共收集16 244个标准体型成年病例的剂量数据,经逐一检查剔除274个无效数据,剩余15 970个病例数据。全国范围内不同的CT使用单位,同一检查项目的CTDI_vol、DLP和扫描期项都有很大差异。与国际放射防护组织发布的数据相比,不同检查项目的诊断参考水平的差异程度各不相同,颅脑诊断水平与参考值相当、胸部腹部较低。剂量指数值最大的几种检查项目为头颅、冠状动脉CTA、颅脑CTA和鼻窦。尿路造影的CTDI_vol虽然仅为20 mGy,但DLP却高达2 620 mGy·cm。结论 我国现有的CT剂量水平与国际相关组织发布的诊断标准水平（DRL）不符,需要根据我国的实际建立自己的DRL。     

基于辐射剂量结构化报告的CT辐射剂量分析

目的：应用医学数字成像和通信（ DICOM ）标准定义的辐射剂量结构化报告（ RDSR）,实现CT检查的辐射剂量统计分析。方法利用自行设计的软件,通过检索影像归档和通信系统（ PACS）,获取1230份CT检查的RDSR文件。将相关信息提取后,结合扫描部位建立患者剂量数据库。根据年龄将患者分为成年组（10岁以上）及儿童组（0～1岁,1～5岁,5～10岁）,分别统计各扫描部位的平均容积CT剂量指数（ CTDIvol ）、剂量长度乘积（ DLP）,估算有效剂量（ E）;并计算75％分位DLP值,与诊断学参考水平（ DRL）相比较。结果成年患者组,CTDIvol与DLP值呈中度正相关（r＝0?41）,上腹部增强扫描的E最高,其75％分位DLP值超过DRL60％;儿童5～10岁组的CTDIvol高于0～1岁与1～5岁组（t＝2?42、2?04,P＜0?05）, DLP值与年龄呈低度正相关（r＝0?16）,E与年龄呈中度负相关（r＝-0?48）。结论应用RDSR获得患者辐射剂量是一种简单、高效的方法。随着新设备的普及与区域化医疗平台的应用,RDSR将成为剂量学水平调查及个人剂量记录的主要工具。     

介入诊疗医务人员正确维护辐射防护用具的最佳证据

【摘要】 目的 总结介入诊疗医务人员正确维护辐射防护用具的最佳证据。方法 检索PubMed、Embase、Web of Science、美国指南网（national guideline clearinghouse,NGC）、The Cochrane Library、中国医脉通指南网、中国知网（CNKI）、万方（Wan Fang Data）、维普（VIP）、中国生物医学文献数据库（CBM）中关于介入诊疗医务人员正确维护辐射防护用具的所有证据,包括系统评价、原始研究、专家共识及指南,同时追溯纳入文献的参考文献。检索时限为建库至2021年1月。由2名研究者对纳入的文献质量进行评价,并进行证据提取。结果 共纳入文献12篇,包括类实验研究9篇,专家共识1篇,专家意见2篇,最终总结了7条最佳证据。结论 通过汇总介入诊疗医务人员辐射防护用具的维护和管理的相关证据,为介入诊疗医务人员合理、规范地管理和维护辐射防护用具提供依据。     

功能MRI在儿童肾脏疾病诊断中的研究进展

儿童肾脏疾病可导致肾功能持续下降,需及时监测并控制其进展。目前,多种功能MRI（fMRI）技术已逐步用于儿童肾脏研究,不仅能明确肾脏结构有无异常,还可从肾脏水分子扩散、血氧水平等微观角度对肾功能进行评估,包括扩散加权成像（DWI）、扩散张量成像（DTI）、扩散张量纤维束示踪成像（DTT）、扩散峰度成像（DKI）、血氧水平依赖（BOLD）成像、MR灌注成像。介绍儿童肾脏的生理解剖特点,并综述fMRI在肾脏发育异常、慢性肾脏病、感染性病变、肿瘤性病变等多种疾病中的研究进展。     

美国10种成人CT检查的诊断参考水平和可用剂量

正摘要目的通过CT剂量指数记录,基于病人体型建立美国10个最常用成人CT检查的诊断参考水平(DRL)和可用剂量(AD)。材料与方法本研究分析了583个单位的10     

对ESGAR和ESPR肠道成像检查技术首次联合声明（2017）的解读

【摘要】2017由欧洲胃肠和腹部放射学会（ESGAR）及欧洲儿科放射学会（ESPR）组成的专家委员会,首次发布了针对小肠和结肠成像的患者准备及技术参数的联合共识。该共识在大量文献基础上结合改良Delphi程序而推出,旨在规范检查流程,统一检查技术,提高对肠道疾病的诊断水平,为今后的临床和科研工作提供指导。其中129项声明（82%）为立即达成共识,19项（12%）经修改后达成共识,而有9项（6%）被否决。目前国内尚未有相关介绍,因此本文将对共识中涉及的CT、MRI（口服法,插管法）和超声等肠道成像检查的技术规范进行详细解读。     

小儿慢性咳嗽程序式诊断方法在二级医院中的应用

慢性咳嗽是儿科常见的临床症状,其病因复杂。诊断有一定困难,易致病程迁延,误诊、误治的现象在临床非常常见。为了规范和指导儿科医生对慢性咳嗽的诊断和治疗,中华医学会儿科学分会呼吸学组、《中华儿科杂志》编辑委员会于2007年12月制定了“儿童慢性咳嗽诊断与治疗指南（试行）”（以下简称“指南”）,为临床带来很好的指导作用。现就近年来该指南在临床工作中的应用体会,做如下总结。     

Bonn call for action and the unfinished task of radiation protection of children and adolescents in low and middle-income countries: A focus on Sub-Saharan Africa

ObjectivesThe Bonn call for action, with the theme: “Setting the scene for the next decade,” was declared over nine years ago to strengthen radiation protection in medicine. This study reviews key actions and activities related to radiation protection of children and adolescents consistent with the Bonn call for action in sub-Saharan Africa to highlight progress and identify existing gaps.Key findingsA lot has happened since the declaration of the Bonn call-for-action such as a follow-up conference in 2017 on achieving change in the practice of radiation protection. However, there exists a huge gap that needs to be filled in the radiation protection of children and adolescents in low and middle-income countries particularly sub-Saharan Africa, where limited resources in health compete with radiation protection demands. Some of the gaps that remain are the apparent lack of implementation of the use of referral guidelines and establishment of national and regional diagnostic reference levels for paediatric imaging among others.ConclusionSeveral strides have been achieved on a global scale for the Bonn call for action, ranging from the justification of medical exposures to the current drive for radiation safety culture in medical imaging. However, several unmet needs for radiation protection for children and adolescents remain such as implementation of referral guidelines for justification and paediatric diagnostic reference levels.Implications for practiceStep up actions and close collaboration is required to strengthen the practice of paediatric radiation protection in low and middle-income countries because children account for a greater proportion of the population and are vulnerable to the negative effects of radiation like possible cancer induction.     

Diagnostic reference levels in paediatric fluoroscopy: how does a secondary referral centre compare with 2018 European guidelines?

Objectives:To compare diagnostic reference levels (DRLs) in paediatric fluoroscopy at a secondary referral centre with 2018 European guidelines. Secondly, to compare secondary referral centre DRLs for paediatric fluoroscopy examinations not included in European guidelines with 2010 national UK DRLs.Methods:Paediatric fluoroscopy studies were grouped by age (groups: 0, 1, 5, 10, 15 years) for examination type and analysed retrospectively, over a period of 14 years. DRLs were compared with European DRLs (micturating cystourethrograms (MCUs)) and 2010 UK national DRLs (contrast swallows and meals).Results:1,586 studies were performed (49% MCUs; 31% meals; 9% swallows). For all age groups, DRLs for MCUs were lower than European DRLs by up to a factor 58 x (1 year age group: secondary referral centre DRL 12 mGycm² vs European DRL 700 mGycm²). For contrast swallows and meals, 75^th percentile doses were lower than 2010 UK national 25^th percentile doses in all age groups.Conclusion:Maintaining low doses of ionising radiation is particularly important in paediatrics, and our study has found that it is possible to achieve low paediatric fluoroscopy doses in a secondary referral centre setting.Advances in knowledge:Our data may prove useful to other centres and could contribute towards future European DRLs.     

Traumaradiologie beim Kind

The aim of this review article is to familiarize the reader with the specific paediatric conditions in trauma radiology. The article briefly describes the major pathophysiologic differences in childhood and the consecutive altered injury pattern. The standard radiological imaging protocol for various involved body regions and different trauma settings/varying queries is described, with suggestion for standardised diagnostic flow-charts in some typical settings. Special regard is given to radiation protection and the potential of newer imaging modalities such as ultrasound, multi-detector- and spiral CT as well as MRI in paediatric trauma patients. As such the paper hopefully provides some basic guidelines for general radiologists in peripheral hospitals who less often have to deal with paediatric queries.     

Diagnostic reference levels for thorax X-ray examinations of paediatric patients

Based on the Medical Exposure Directive of the European Commission, 97/43/Euratom, The Radiation and Nuclear Safety Authority (STUK) in Finland has the responsibility for setting national diagnostic reference levels (DRLs) for the most common radiological examinations. Paediatric patients deserve special attention because of the higher radiation risk compared with adults. The purpose of this paper is to present a method that takes into account patient size when setting DRLs in paediatric patients. The overall data consisted of patient doses collected from six hospitals during the years 1994-2001, and new measurements in two hospitals in 2004. In total, there were 700 chest examinations. The method established by the National Radiological Protection Board (UK) for setting DRLs was not considered feasible in Finnish practice. Patient doses correlated exponentially with the projection thickness, which was measured directly for each patient. Since 1 January 2006, paediatric DRLs for conventional chest examinations have been specified in Finland as a DRL curve by using both dose quantities (entrance surface doses (ESD) and dose-area product (DAP)) as a function of patient projection thickness.     

Dose audit for patients undergoing two common radiography examinations with digital radiology systems

PURPOSE

We aimed to determine the radiation doses delivered to patients undergoing general examinations using computed or digital radiography systems in Turkey.

MATERIALS AND METHODS

Radiographs of 20 patients undergoing posteroanterior chest X-ray and of 20 patients undergoing anteroposterior kidney-ureter-bladder radiography were evaluated in five X-ray rooms at four local hospitals in the Ankara region. Currently, almost all radiology departments in Turkey have switched from conventional radiography systems to computed radiography or digital radiography systems. Patient dose was measured for both systems. The results were compared with published diagnostic reference levels (DRLs) from the European Union and International Atomic Energy Agency.

RESULTS

The average entrance surface doses (ESDs) for chest examinations exceeded established international DRLs at two of the X-ray rooms in a hospital with computed radiography. All of the other ESD measurements were approximately equal to or below the DRLs for both examinations in all of the remaining hospitals. Improper adjustment of the exposure parameters, uncalibrated automatic exposure control systems, and failure of the technologists to choose exposure parameters properly were problems we noticed during the study.

CONCLUSION

This study is an initial attempt at establishing local DRL values for digital radiography systems, and will provide a benchmark so that the authorities can establish reference dose levels for diagnostic radiology in Turkey.Standard radiology procedures in projection radiography (plain films or digital equipment) account for 48% of all diagnostic radiology examinations and contribute 41% to the collective dose (1). One of the main reasons for introducing the diagnostic reference level (DRL) concept was to investigate situations where patient doses are unusually high. Therefore, DRLs provide a valuable method for dose optimization (2). The as-low-as-reasonably-achievable principle should be considered in such dose-optimization processes. Surveys have shown variation by as much as two magnitudes in the doses to patients undergoing the same X-ray examinations (3). This wide variation in patient dose proves that there is room to optimize the radiography process. There is also considerable evidence that substantial reductions in these medical exposures are possible without detriment to patient care (4).To reduce the radiation dose to the patient, guidelines must be followed for appropriate levels of exposure. The International Commission on Radiological Protection (ICRP) and European Commission have recommended the use of DRLs (3–5). It has been recommended that the 75th percentile or third quartile of the dose distribution in a population of standard-sized patients is an appropriate level for the DRL (5). According to the Commission of European Communities, the purpose of DRLs is to encourage radiology departments to investigate their patient radiation doses and make historical, national, or international comparisons (6). To our knowledge, there are no published Turkish data on patient doses in general radiography with digital X-ray systems. Torres et al. (7) made the following statement: the implementation of these new technologies requires an estimation of the doses that are actually being administered in clinical practice, in order to check that, in cases of both day-to-day practice and optimization protocols, doses are kept within reference values and as low as achievable in relation to the aimed image quality. This statement also holds true for Turkey.In Turkey, many X-ray examinations are performed using new technologies such as computed radiography (CR) and direct digital radiography (DR), although no DRLs for conventional radiography practices published by national authorities have investigated this new equipment, which has the potential to deliver lower patient doses than previous X-ray devices. Council Directive 97/43 of the European Atomic Energy Community defines DRL and expects member states to promote the establishment of DRLs for radiodiagnostic examinations. Therefore, national DRLs should be defined by national authorities, and European levels have already been established.The objectives of this study were to perform a radiation dose audit, to compare the results of the patient dose survey with international DRLs for both examinations, to present the study results to radiologists in Turkey in order to draw attention to the patient doses using digital radiography systems, and to observe improper practices in the clinics studied.     

Health effects of radiation exposure in diagnostic radiology

For risk estimations, scientists have at their disposition results from molecular, cellular and animal experiments, risk modelling and human epidemiological studies. Much has been achieved, but large uncertainties in quantitative risk estimates of exposure of humans to low levels of ionising radiation still remain. Radiation risks in diagnostic radiology are reviewed in this paper. The paper addresses stochastic as well as deterministic effects. Risks for adult, paediatric and prenatal exposures are discussed. It is concluded that a pragmatic approach for radiation protection in diagnostic radiology is indicated, i.e. precautionary measures should be taken even if some cause-and-effect relationships are not fully established scientifically.     

加强放射诊断辐射剂量管理的必要性及应对策略

近年来, 我国放射诊断检查特别是CT检查的频次迅猛增加, 已经成为国民人均辐射剂量的最大人工辐射来源, 并有可能超过天然辐射源的贡献。临床诊疗活动中, 患者和受检者短时间内可能进行多项目、多频次的放射诊断成像, 所接受的累积辐射剂量较高, 甚至一天检查的剂量贡献超过50或100 mSv, 从而对其健康产生潜在风险。因此, 有必要对放射诊断辐射剂量信息进行统计分析与控制管理, 以尽可能降低过高剂量及其辐射危险的发生概率。本文对放射诊断辐射风险的国际认识、我国放射诊断设备和检查频次、放射诊断辐射剂量及其管理现状进行阐述, 并就辐射剂量的管理提出应对策略, 为进一步推进临床实践中的辐射防护提供参考。     

Common tasks and problems in paediatric trauma radiology

Scope of this article is to give practical hints for the most common, typical and important topics of trauma radiology in children to those radiologists who are not exclusively occupied with paediatric imaging. Due to the increased radiation sensitivity of children compared with adults balancing radiation protection and necessary image quality is of utmost importance. Outlines for this optimisation process are given. Especially in imaging of the extremities perhaps the greatest difficulties are posed by the dynamically changing face of the immature, growing, only partially ossified skeleton. Lack of experience must be compensated by meticulous comparison with the normal skeletal development as shown in standard textbooks, and by knowledge of the radiological image of the developmental variants. Besides general remarks about paediatric trauma radiology, some important topics are discussed into more detail. Especially the elbow joint poses a challenge for those less experienced with its radiological appearance in children. More than in adults, ultrasound should remain the primary imaging modality of choice especially in the assessment of abdominal trauma, and CT be tailored to radiological and clinical findings. Imaging and diagnosis of non-accidental injury (NAI) may be a less common task for the general radiologist, however, the severe social implications of physical child abuse mandate a basic knowledge about the radiological symptoms and the imaging management of this problem for all physicians occupied with paediatric radiology.     

Population exposure to ionizing radiation from medical examinations in France

This study was carried out to update data concerning both the nature and the frequency of X-ray diagnostic procedures and to reassess the associated per caput effective dose in France, given that the only nationwide survey was carried out over 15 years ago. Relevant data concerning examinations in conventional radiology, computed tomography, interventional radiology and nuclear medicine were obtained for the year 2002 from two main sources: the main health insurance records for private practices and the statistics of healthcare establishments on hospital activity. Doses associated with different types of examination were obtained from the diagnostic reference levels (DRL) campaign, together with data from the European Commission and from the Health Protection Agency in the UK. The results show that between 55.4 and 65.9 million procedures were performed in 2002 in conventional radiology (one-third for dental) and between 4.2 and 6 million in computed tomography. There were 850,000 and 900,000 procedures in nuclear medicine and interventional radiology respectively. Conventional radiology accounts for 90% of the total number of procedures but only 37% of the collective dose, whereas examinations in computed tomography account for 8% of total examinations but 39% of the collective dose. Examinations in nuclear medicine and interventional radiology account for 2% of procedures but 7% and 17% of the collective dose respectively. Finally, the per caput effective dose in 2002 was between 0.66 and 0.83 mSv.