本刊2020年度“指南”类文章刊登预告

自创刊以来,本刊致力于为广大放射治疗工作人员提供最有价值的阅读资料。为更好地服务于读者,2020年度本刊将陆续刊登以下“指南”:《医用电子直线加速器质量控制指南》、《后装治疗机的质量控制和质量保证》、《螺旋断层放疗系统的质量保证》、《放射治疗记录与验证系统质量控制指南》、《调强放疗剂量验证实践指南》,以飨读者.     

放射治疗的质量控制和质量保证

随着肿瘤放射治疗事业的发展和高精尖的科学技术应用于临床 ,质量保证(QA)和质量控制 (QC)日益完善 ,并受到肿瘤放疗学界的重视 ,QA、QC的水平体现着肿瘤放疗的水平。放射治疗的QA、QC是指经过周密计划和必要措施保证放射治疗的整个过程准确安全执行。对于所使用的放疗设备的检测和调整、各治疗机剂量监测系统的检测和校对、治疗计划系统的验证及治疗中辐射安全已成为定期常规检测的 QA、QC的收稿日期 :2 0 0 0 -0 7-2 2作者单位 :河北医科大学第四医院 ,　河北　石家庄　 0 5 0 0 0 0基本内容。为了提高肿瘤放射治疗的质量 ,特别是…     

四川省基层放疗单位医用直线加速器剂量和机械性能抽样分析

目的 对四川省基层放疗单位医用电子直线加速器进行剂量和机械性能抽样核查。方法 抽样选取四川省8家放疗单位,对其正在使用的医用电子直线加速器进行剂量和机械性能检测,其中包括5台进口加速器,3台国产加速器,检测项目和检测方法依据GB15213-94的要求执行。结果 14项检测结果中,未达国家标准的项目集中在辐射野平坦度、对称性和辐射野光野重合性方面,其他剂量精度检测和机械精度检测结果均较好。结论 亟待加强四川省基层放疗单位医用直线加速器日常剂量精度和机械精度QC工作,完善专业检测设备和专业人员配置及相关人员培训。需要以四川省放疗质量控制中心为依托,积极开展覆盖全省的放疗机QC监督指导工作。     

基于患者出射EPID剂量验证的在体调强放疗质控技术研究

背景与目的：调强放疗（intensity-modulated radiation therapy，IMRT）中剂量投照失误可导致严重后果，而目前常用的治疗前计划验证方法并不能反映患者真实投照剂量。实现一种评估患者在体剂量执行准确度的方法，能够在分次治疗中及时发现较大剂量错误，避免发生患者投照剂量过高或不足。方法：复旦大学附属肿瘤医院收治的患者首次实施治疗前行锥形束计算机断层成像（cone beam computed tomography，CBCT）扫描，与定位CT图像进行配准保证治疗体位与模拟定位时一致，实时治疗中使用电子射野影像装置（electronic portal imaging device，EPID）获取患者出射剂量影像，并把首次出射EPID影像作为剩余分次治疗的基准值，后续分次实时治疗野结束后快速将其出射EPID影像与对应基准影像进行γ分析比较，以验证治疗计划是否准确执行于患者身上。设计模体实验对治疗部位错误和摆位误差情况进行分析，来评估本方法识别放疗差错的准确性。结果：本方法可有效地识别出IMRT放疗中患者治疗部位错误和非平行于射野角度方向的摆位误差，但对平行于射野角度方向的摆位误差并不敏感，30例鼻咽癌患者临床应用结果中能够直观显示分次治疗间摆位重复性情况。结论：基于EPID实现的一种在体剂量验证方法能够对调强放疗中患者实时剂量的准确性进行评估，在单个治疗野结束后可快速检测出较大治疗错误。     

放疗网络的临床应用

目的 探讨放疗网络在临床的应用和意义。方法 放疗网络是放疗科内的局域计算机网络，将放疗及与放疗相关的设备通过网络连在一起，对患者资料进行系统管理，对放疗科工作人员按其职能权限进行分工。通过网络系统获得模拟定位机和治疗计划系统的治疗数据，在加速器治疗机上自动设置治疗参数，对每个患者的照射野、照射剂量进行检测和限制。结果 对接受治疗的150例患者进行了从病历号录入、定位、计划、验证和治疗的计算机管理，有7例需要加量治疗的患者，计算机提示并停止原治疗计划，由主管医生修正治疗计划后继续治疗。结论 放疗网络的应用避免了数据传输、人工输入中的误差，是放射治疗临床质量保证和质量控制的工具。     

调强放疗剂量验证实践指南

调强放疗剂量验证是放疗质量保证的重要组成部分,对保证调强放疗的安全和质量非常重要。我国尚无调强放疗剂量验证的系统指南和验证工具方法的具体推荐,验证结果的解读及其临床意义、验证不通过的原因分析及处理措施,不同机构使用的工具方法和实施细节差异很大。在国家肿瘤诊疗质控中心放疗质控专家委员会的组织领导下,经过现状调查、多中心测试、专家研讨、咨询、审定等方式完成了该指南。指南规定了开展调强放疗剂量验证的机构、组织、人员、设备、技术流程,及文档记录等方面的要求,以期改进调强放疗剂量验证工作的规范化开展。     

肿瘤放疗信息网络一体化管理平台的研发及临床实践

目的：研制开发流程管理与质量保证功能一体化的肿瘤放疗信息网络管理系统并评估其临床应用价值。方法基于放疗流程和质量保证、质量控制的要求,以客户－服务器端（ C－S）模式,采用SQL SERVER 2008数据库结构和国际标准DICOM 3．0、DICOM RT及HL7协议,通过局域网络系统硬件和自研发软件,搭建放疗信息网络管理系统,并通过临床测试评价系统的运行性能。结果开发了统一界面的交互式一体化管理系统平台与客户端应用功能模块;研发了安全可靠的标准化数据接口,可与主流厂商加速器、治疗计划系统以及医院信息系统等连接使用;完成了放疗流程管理和质量保证管理模块的设计与开发;通过了系统运行前测试并在临床科室上线使用近3年,证实了系统运行安全稳定并实现了系统设计的全部功能。结论一体化管理系统可以满足肿瘤放疗信息数据的应用管理需求,提高了放疗科整体工作效率和质量保证与质量控制水平,可作为肿瘤放疗科工作的良好工具进行推广应用。     

调强放疗中剂量验证方法的探究

[目的]探究调强放疗计划的剂量验证方法.[方法]利用Varian Clinal CX 4994号医用电子直线加速器出束的6MV能量X射线,对通过Eclipse 8.6治疗计划系统设计的调强放疗计划,采用PTW二维电离室矩阵进行平面剂量验证,采用Gamma分析.[结果]86.1％(292/339)的调强放疗计划绝对剂量通过率≥90.0％.[结论]使用二维电离室矩阵,进行调强放疗患者的个体化剂量验证,简单可靠,完善了调强放疗剂量验证体系.     

放疗自动计划研究进展

常规放疗计划设计是一个耗时耗力的过程,需要在计划优化中不断调整参数来寻找最优计划。此外,计划设计者之间的经验差异、投入计划设计的时间以及医疗机构的执行标准都会影响计划质量,从而影响临床治疗效果以及患者预后。近年来自动计划发展迅速,自动计划能够在保证计划质量前提下提升计划设计效率。当前已有一些方法致力于放疗计划设计的自动化,如Eclipse和Pinnacle商用治疗计划系统中的Rapid Plan和Auto-Planning功能,也有研究将人工智能技术应用于剂量预测以实现自动计划。本文对现有的放疗自动计划研究做一综述,介绍各类自动计划方法的实现原理、临床效果以及存在的问题。     

放射治疗计划执行中如何做好技术员工作质量保证的几点想法

放射治疗全过程主要分为治疗计划的设计和治疗计划的执行两大阶段 ,治疗计划的执行在某种意义是治疗计划设计的逆过程 ,本阶段的中心任务是保证病人体内得到计划设计阶段所规定的靶区剂量大小及其相应的剂量分布。为了保证靶区剂量的准确性达到± 5 % ,ＱＡ(质量保证 ) [1 ] 要求因治疗机参数变化而造成的射野偏移允许 <5ｍｍ、因病人或体内器官运动和摆位时允许的误差 <8ｍｍ。如果本阶段治疗机已通过ＱＡ(质量保证 )和ＱＣ[1 ] (质量控制 )的保证 ,那么技术员的开作质量对放射治疗计划执行的精度至关重要 ,技术员是放疗计划的执行者 ,每天…     

Guidelines on quality control of radiotherapy record and verification system

Radiotherapy Record and Verification System (RVS) is a medical software control system applied to prevent wrong parameter settings in radiotherapy machines, such as medical linear accelerators, and to record all the execution parameters in the process of radiotherapy. To ensure the safety of patient treatment, necessary quality control measures must be taken for RVS. The guidelines cover the following topics:quality control in RVS installation and parameter setting, acceptance of RVS, quality control of RVS in clinical practice, typical error types encountered in RVS and examples of acceptance test of RVS.     

医用电子直线加速器质量控制指南

随着放疗技术的发展,我国已进入精准放疗时代。医用电子直线加速器作为放疗的主要设备,能否做好质量控制工作,使之可靠运行,是保证放疗精确实施的先决条件。本指南为国内医疗机构制定本单位的医用电子直线加速器质控方法提供指导,范围涵盖机械性能、安全联锁、剂量学性能、图像引导、特殊照射等多方面内容。在制定指南时,以已发布的国内外相关标准为依据,旨在将国内各机构的质控项目统一化。使用医用电子直线加速器进行放疗的医疗机构应配备相应的质控人员,建议每台加速器至少配1名医学物理师。对于日检项目,由技师或医学物理师完成;对于月检及年检项目,由医学物理师完成。参加质控的人员须持证上岗并经过完善培训,测量结果由高年资医学物理师审核并存档。     

How to Respond to a Ransomware Attack? One Radiation Oncology Department's Response to a Cyber-Attack on Their Record and Verify System

The digitization of healthcare for patient safety and efficiency introduced third party networks into closed hospital systems increasing the probability of cyberattacks and their consequences(1). In April 2021, a major vendor of a Radiation Oncology (RO) record and verify system (RVS) suffered a ransomware attack, affecting our department and many others across the United States. This article summarizes our response to the ransomware event including workflows, team member roles, responsibilities, communications and departmental recovery. The RVS created or housed accurate patient dose records for 6 locations. The immediate response to the ransomware attack was to shut down the system including the ability to treat patients. With the utilization of the hospital EMR and pre-existing interfaces with RVS, the department was able to safely continue patient radiotherapy treatments innovatively utilizing a direct Digital Imaging and Communications in Medicine (DICOM) transfer of patient data to the linear accelerators and implementing paper charting. No patients were treated in the first 24 hours of the attack. Within 48 hours of the ransomware event, 50% of patients were treated, and within 1 week, 95% of all patients were treated using direct DICOM transfer and paper charts. The RVS was completely unavailable for 2.5 weeks and full functionality was not restored for 4.5 weeks. A phased approach was adopted for re-introduction of patient treatments back into the RVS. Human capital costs included communication, outreach, workflow creation, quality assurance and extended clinical hours. Key lessons learned were to have a back-up of essential information, employ ‘dry run’ emergency training, having consistent parameter requirements across different vendor hardware and software, and having a plan for the recovery effort of restoring normal operations once software is operational. The provided report presents valuable information for the development of cyber-attack preparedness for RO departments.     

Quality assurance of helical tomotherapy

Helical Tomotherapy combines a form of intensity-modulated radiation therapy (IMRT) with the accuracy of computed tomography (CT) scanning technology in one machine. HT is one of the most advanced radiotherapy equipments at present. Considering the difference from the quality assurance of conventional linear accelerators, this guideline was proposed by National Cancer Center/National Cancer Quality Control Center, and multiple medical institutions participated in the formulation of this guideline. The guideline includes the acceptance items, operating rules and emergency plans, etc. The test methods, tolerances and frequencies of HT quality assurance are clarified. According to the actual situation of domestic medical institutions, the guideline provides recommended testing items, mainly including mechanical accuracy, dosimetric parameters, laser system, couch motion accuracy, MVCT imaging system quality control testing and clinical treatment plan verification, etc., making the guideline highly operable. This guideline can provide clinical phycicians with technical guidance on quality assurance, make quality assurance work rule-based, and improve the accuracy and precision of radiotherapy. It has instructive implications for medical institutions to establish standardized HT quality assurance system.     

螺旋断层治疗系统的质量保证

螺旋断层治疗系统(HT)是一种集调强放射治疗和影像引导放射治疗于一体的放射治疗系统,是目前最先进的放疗设备之一。考虑其与常规直线加速器质量保证的差异,由国家癌症中心/国家肿瘤质控中心提出,多家医疗单位共同参与制定了本指南。指南包括国内医疗机构HT用于临床工作的验收项目、操作制度、应急预案等内容,明确了质量控制的测试方法、评价标准、检测频率。指南结合国内医疗单位实际情况给出了推荐性检测项目,主要包括机械精度、剂量输出与分布、激光定位系统、治疗床运动精度、MVCT影像系统质控检测、临床治疗计划验证等具体实施方法步骤,使得指南具有很强的可操作性。本指南能给临床工作人员提供质量保证技术指导,使HT质量保证工作有章可循,可提高放射治疗的准确性和精度。对国内各医疗机构建立规范HT质量保证体系具有指导意义。     

浙江省肿瘤放疗质控检查报告

目的 通过放疗质控检查发现存在的问题,提出改进的建议或措施。方法 对浙江省内有放疗设备的45家医院进行全面的放疗质控检查,检查内容包括物理、技术、临床工作及放疗流程中与质控有关的各项参数结果 截止 2017年12月31日,45家单位共有直线加速器62台,在放疗过程中,放疗设备配置、临床工作质量、放疗技术及人员资质等方面还存在很多质控方面的问题,包括设备配置的不合理,放疗工作人员不足、临床工作流程和物理技术放疗的质量保障仍有待提高结论 定期开展放疗质控工作,对确保放疗的精准有效和医疗安全非常重要。     

Evaluation of frequency and type of errors detected by a computerized record and verify system during radiation treatment.

BACKGROUND: Computerized record and verify systems (RVS) have been introduced to improve the precision of radiation treatment delivery. These systems prevent the delivery of ionizing radiations when the settings of the treatment machine do not match the intended parameters within some maximal authorized deviation. PURPOSE: To assess the potential alteration of the frequency of errors associated with the use of RVS during radiation treatment delivery. MATERIALS AND METHODS: The software of the RVS was altered in order to record the settings actually used for radiation treatment delivery whereas the verification function was suppressed. At the end of the study period, the settings used during daily administration of radiation treatment were compared to the parameters recorded in the RVS using the computer. They were also compared with the planned ones written in the patient treatment chart. RESULTS: Out of the 147,476 parameters examined during the study period, 678 (0.46%) were set erroneously. At least one error occurred in 628 (3.22%) of the 19,512 treated fields. An erroneous parameter was introduced in the RVS memory in 22 (1.17%) of the 1885 fields. CONCLUSIONS: RVS has the potential to improve precision of radiation treatment delivery by detecting a significant number of setting errors. However, excessive confidence in RVS could lead to repeated errors as there is a potential for the entry of erroneous parameters into the RVS memory.     

乳腺癌保乳术后大分割放疗的临床研究进展

乳腺癌保乳术后行全乳腺放疗在降低局部肿瘤复发同时也可改善患者生存情况。虽然全乳腺标准放疗可以实现良好的肿瘤控制及美容效果,且具有不良反应轻的特点,但5~7周的治疗时间对患者相对较长,甚至可能造成医疗资源浪费,因此临床上越来越倾向大分割放疗和加速部分乳腺照射的短疗程放疗。短疗程放疗与常规分割放疗均为安全有效的治疗模式,具有与常规放疗相似的生存和局部肿瘤控制效果,不良反应可以耐受。相较于常规分割放疗,短疗程放疗具有缩短治疗总时间,减少治疗费用,节约医疗资源,改善患者生存质量的显著优势。      

Comparison of quality assurance for performance and safety characteristics of the facility for Boron Neutron Capture therapy in Petten/NL with medical electron accelerators.

BACKGROUND AND PURPOSE: The European Council Directive on health protection 97/43/EURATOM requires radiotherapy quality assurance programmes for performance and safety characteristics including acceptance and repeated tests. For Boron Neutron Capture therapy (BNCT) at the High Flux Reactor (HFR) in Petten/NL such a programme has been developed on the basis of IEC publications for medical electron accelerators. RESULTS: The fundamental differences of clinical dosimetry for medical electron accelerators and BNCT are presented and the order of magnitude of dose components and their stability and that of the main other influencing parameter 10B concentration for BNCT patient treatments. A comparison is given for requirements for accelerators and BNCT units indicating items which are not transferable, equal or additional. Preliminary results of in vivo measurements done with a set of 55Mn, 63Cu and 197Au activation foils for all single fields for the four fractions at all 15 treated patients show with < +/- 4% up to now a worse reproducibility than the used dose monitoring systems (+/- 1.5%) caused by influence of hair position on the foil-skull distance. CONCLUSIONS: Despite the more complex clinical dosimetry (because of four relevant dose components, partly of different linear energy transfer (LET)) BNCT can be regulated following the principles of quality assurance procedures for therapy with medical electron accelerators. The reproducibility of applied neutron fluence (proportional to absorbed doses) and the main safety aspects are equal for all teletherapy methods including BNCT.     

Use of 'sham' radiotherapy in randomized clinical trials

The objective of this systematic review was to identify quality trials that use sham radiotherapy in their design and review them to determine its potential value. The Cochrane Library, Pubmed and a Reference Search served as data sources. Trials were included if they met a minimum quality score of 3 on a validated assessment instrument (which assesses randomization, control and blinding) and if they compared sham radiotherapy to active treatment. External beam therapy and brachytherapy trials were considered. Twenty-six trials were identified, collectively including 2663 participants in the period of 1970-2004. All the trials studied the value of radiotherapy for treatment or prevention of benign diseases, including multiple sclerosis, coronary artery restenosis, age-related macular degeneration and Graves' ophthalmopathy. There were no trials relating to the use of radiotherapy in the treatment of malignancy. This review showed that it is possible to carry out sham radiotherapy with due regard for ethical concerns, with effective blinding and high levels of patient acceptance. Large sample sizes with multicentre trial designs were achievable. Although the statistical philosophy for using sham radiotherapy in trials is legitimate, it is no longer routinely used.