Radiation Protection in Radiotherapy

Radiation Protection inRadiotherapyPart 12Quality AssuranceIAEA Training Material on Radiation Protection in Radiotherapy

Part 12: Quality assurance

Radiation Protection in Radiotherapy

QUALITY as a goalThe totality of features or characteristics that bear on our ability to satisfy the stated or implied goal of effective patient care.Comprehensive QA for Radiation Oncology, AAPM Task Group 40, 1994To ensure the goal is reached requires a fully implemented Quality Assurance program throughout the facility.



What is Quality Assurance?All those planned and systematic actions necessary to provide confidence that a product or service will satisfy given requirements for quality.ISO 9000



Quality AssuranceIn the BSS seen in the context of medical exposure as essential for radiation protection of the patientQuality Assurance and Control is also important to assess the overall effectiveness of protection and safety measures



ObjectivesTo be familiar with the concepts of Quality Assurance as a multidisciplinary activity and its interrelation with radiation protection in radiotherapy.To be familiar with Quality Assurance procedures as a tool for reviewing and assessing the overall effectiveness of a radiation protection program. To be able to understand the need for and role of specific tests in the context of Quality Control and be able to identify appropriate national and international protocols for this task To be aware of the need for involvement of professionals in a Quality Assurance program and for radiation protection



Contents1. Quality Assurance and the BSS2. QA systems3. Quality Control in radiotherapyExternal Beam RTBrachytherapy4. QA and radiation protection



1. Quality Assurance and the BSS (Managerial Requirements)BSS 2.29. Quality assurance programmes shall be established that provide, as appropriate: (a) adequate assurance that the specified requirements relating to protection and safety are satisfied; and (b) quality control mechanisms and procedures for reviewing and assessing the overall effectiveness of protection and safety measures.



QA and QCQuality Assurance is the overall process which is supported by Quality Control activitiesQuality Control describes the actual mechanisms and procedures by which one can assure quality



Quality Assurance and Medical ExposureBSS appendix II.22. Registrants and licensees, in addition to applying the relevant requirements for quality assurance specified elsewhere in the Standards, shall establish a comprehensive quality assurance programme for medical exposures with the participation of appropriate qualified experts in the relevant fields, such as radiophysics or radiopharmacy, taking into account the principles established by the WHO and the PAHO.You must establish a QA program!



Relevant for radiotherapyWORLD HEALTH ORGANIZATION, Quality Assurance in Radiotherapy, WHO, Geneva (1988).PAN AMERICAN HEALTH ORGANIZATION, Publicacin Cientifica No. 499, Control de Calidad en Radioterapia: Aspectos Clnicos y Fsicos, PAHO, Washington, DC (1986).



BSS appendix II.23Quality assurance programmes for medical exposures shall include: (a) measurements of the physical parameters of the radiation generators, imaging devices and irradiation installations at the time of commissioning and periodically thereafter; (b) verification of the appropriate physical and clinical factors used in patient diagnosis or treatment; Check machine and data!



Consequences for radiotherapyA good acceptance testing and commissioning program is fundamental for any QA activitiesQA activities are typically a subset of the tests and procedures used for the commissioning of a unitQA applies to both physical and clinical aspects of the treatment



BSS appendix II.23Quality assurance programmes for medical exposures shall include: ...(c) written records of relevant procedures and results; (d) verification of the appropriate calibration and conditions of operation of dosimetry and monitoring equipment; .



Consequences for radiotherapyTreatment records must be kept of all relevant aspects of the treatment - includingSession and Summary Record informationRecords all treatment parametersDose CalculationsDose Measurements Particular emphasis is placed on QA of dosimetry



Treatment recordsMust contain all relevant informationCan be in electronic format



BSS appendix II.23Quality assurance programmes for medical exposures shall include: ...and (e) as far as possible, regular and independent quality audit reviews of the quality assurance programme for radiotherapy procedures



Consequences for radiotherapyA QA system itself and its outcomes must be critically reviewedExternal audits are recommended to verify that the checks are not only done but that they also achieve what they are supposed to doEvery good system requires an independent look at times



2. QA systemsMany QA systems exist - one important example is the ISO 9000 systemThey are highly successful in manufacturing industry because they do improve productivity and avoid costly mistakes



Good QA systems in radiotherapyImproves work practicesWould have prevented most of the major accidents



ISO 9000Comprehensive set of standards for QA (mainly in manufacturing and service industry)Adapted e.g. by ESTRO to the radiotherapy environmentEuropean Society for Therapeutic Radiology and Oncology (ESTRO) Advisory Report to the Commission of the European Union for the 'Europe Against Cancer Programme'. Quality Assurance in radiotherapy. Radiother. Oncol. 35: 61-73; 1995.



Quick note aside: How to get ISO 9000 certified implementation stepsApplicationPreliminaryPre-auditSystem auditCertification - registrationSurveillance audits



A Comprehensive Quality Assurance ProgramThe details of such a program are often wrapped up in a Code of Practice.Quality Assurance in Radiotherapy, ESTRO Advisory Report, 1995Comprehensive QA for Radiation Oncology: Report of AAPM Radiation Therapy Committee Task Group 40, 1994Quality Assurance in Radiotherapy, WHO, 1988



A Comprehensive QA Program typically comprisesQuality Assurance CommitteePolicies and Procedures ManualQuality Assurance teamQuality auditResources



QA Committee MembershipMust represent the many disciplines within the departmentShould be chaired by the Head of DepartmentAs a minimum must include a medical doctor, a physicist, a radiotherapy technologist and an engineer responsible for service and maintenanceMust be appointed and supported by senior managementMust have sufficient depth of experience to understand the implications of the processMust have the authority and access to the resources to instigate and carry out the QA process



Quality Assurance CommitteeShould represent the departmentShould be visible AND accessible to staffOversees the entire Quality Assurance programWrites policies to ensure the quality of patient careAssists staff in tailoring the program to meet the needs of the Department (using published reports as a guide)Monitor and audit the program to ensure that each component is being performed and documented



Quality Assurance CommitteeSet agreed Action LevelsExample: Physics is given the authority to ensure correct accelerator outputFor the daily output check two Action Levels are setFor any daily measurement which exceeds 2% but less than 4%, treatment may continue but the Senior Physicist responsible must be notified (immediately)For any daily measurement which exceed 4%, treatment must STOP immediately and the problem investigated by the Senior Physicist responsible



Action levelsAre quantitativeReflect the required outcome Are informed by the achievable outcomeMust be unambiguousShould be easy to understand



QA Committee reviewWhere Action Levels have been exceededWhere set procedures have been discovered to be faultyAfter a review, recommendations must be formulated in writing for improving the QA programWhen errors are discovered the fault often lies in the process rather than in the action of individuals



Documentation for the Quality Assurance CommitteeTerms of ReferenceThe Committee must meet at established intervals and retain for audit purposes the minutes of its meetings, actions recommended and the results attained.In short, there is a QA program for the QA Committee



Policies and Procedures ManualThis manual contains clear and concise statements of all the policies and procedures carried out in the DepartmentReviewed (typically) yearlyUpdated as procedures changePolicies and Procedures Manual



Policies and Procedures ManualAs a minimum, sections should exist forAdministrative proceduresClinical proceduresTreatment proceduresPhysics proceduresRadiation safety



Policies and Procedures ManualIt must be signed off by the Head of Department and appropriate section headsIt is important that all staff have ownership to the manual - it should reflect the opinions of all and be agreed to by allA list of all copies of the Manual and their locations must be kept to ensure that each copy is updated



Quality Assurance TeamIncludes all disciplinesWell defined responsibility and reporting structureEach member of the team mustKnow his/her responsibilityBe trained to perform themKnow what actions are to be taken should a test or action be outside the preset action levels



Responsibility ChartLeerAreaProfessional



Quality Assurance TeamEach member of the team must alsoHave at least some understanding of the consequences when tests or actions are outside the action levelsMaintain records documenting the frequency of performance, the results and the corrective action taken if necessary



Quality AuditA systematic and independent examination and evaluation to determine whether quality activities and results comply with planned arrangements and whether the arrangements are implemented effectively and are suitable to achieve the objectives.Quality assurance in radiotherapy., Radiother. Oncol., 1995Do you do what you say you do?



Quality AuditIdeally performed by someone outside of the organisationExamplesIAEA/WHO TLD program for check of dose in therapy unitsEQUAL program in EuropeAudits of clinical trials participation


Quality Assurance does not stop here!The Quality Assurance Committee and the Quality Assurance team must continuously monitor new information and implement this in their procedures



Continuous Quality ImprovementCQI - many other acronyms are available for thisPart of virtually all QA systemsImproved methods on cancer patient management are documented in clinical trial reports.Quality assurance protocols are continuously under development in many countriesRegular Quality Assurance meeting for all members of a SectionContinuing education - lectures, workshops, journal clubs and must be available for all staff



And finally: QA is not a threat, it is an opportunityIt is essential in a QA program that all staff feel free to report errorsA non threatening environment must existReward honesty with encouragementEducation is the key, not punishment



3. Quality Control in radiotherapyMany documents exist that specify what QC activities should be performed in radiotherapy



QC should ensure every step in the treatment chain...e.g.: check sourceactivitye.g.: hand calculation of treatment time



Radiother. Oncol. 1992: > 50 occasions of data transferfrom one point to another for each patient!If one of them is wrong - the overall outcome is affected


Human errors in data transfer during the preparation and delivery of radiation treatment affecting the final result: "garbage in,

Department of Radiotherapy, University Hospital, St. Rafal, Leuven, Belgium

Abstract

Due to the large number of steps and the number of persons involved in the preparation of a radiation treatment, the transfer of information from one step to the next is a very critical point. Errors due to inadequate transfer of information will be reflected in every next step and can seriously affect the final result of the treatment. We studied the frequency and the sources of the transfer errors. A total number of 464 new treatments has been checked over a period of 9 months (January to October 1990). Erroneous data transfer has been detected in 139/24,128 (less than 1%) of the transferred parameters; they affected 26% (119/464) of the checked treatments. Twenty-five of these deviations could have led to large geographical miss or important over- or underdosage (much more than 5%) of the organs in the irradiated volume, thus increasing the complications or decreasing the tumour control probability, if not corrected. Such major deviations, only occurring in 0.1% of the transferred parameters, affected 5% (25/464) of the new treatments. The sources of these large deviations were nearly always human mistakes, whereas a considerable number of the smaller deviations were, in fact, consciously taken decisions to deviate from the intended treatment. Nearly half of the major deviations were introduced during input of the data in the check-and-confirm system, demonstrating that a system aimed to prevent accidental errors, can lead to a considerable number of systematic errors if used as an uncontrolled set-up system. The results of this study show that human mistakes can seriously affect the outcome of patient treatments.(ABSTRACT TRUNCATED AT 250 WORDS) [Journal Article; In English; Netherlands]


QC activities in radiotherapyThree general areas:Physical dosimetryTreatment planning (dealt with part 10 lecture 3C of the course)Patient treatment



QC activitiesMust be planned prospectivelydailyweeklymonthlyannuallywhenever neededThe following is only a suggestion!



A collection of formsConstantinou C.: Protocol and procedures for quality assurance of linear accelerators. Brockton: Constantinou; 1994. Available from Medical Physics Publishing, Madison.



External Beam RadiotherapyExamples for daily QCSafetydoor and other interlocksradiation warning lightsaudiovisualradiation area monitorRadiation constancy checkMechanical/optical pointersPTW Linacheck



Test of optical componentsUsed for patient set-upEssentialEasy to performJigs available

RMI test tool



Alignment of lasers for patient set-upShould point to the isocentreCheck also line widthCheck line alignment at least 20cm beyond isocentre Gammex laser and test tool



Quality Control - WeeklyCheck of source positioning (cobalt 60)Couch movements (lateral, vertical, longitudinal)



Example for weekly QC summary From Constantinou 1992



Quality Control - MonthlyDosimetryOutput constancyBackup monitorsCentral axis %DD constancy Flatness/symmetry constancyTimer end effect



Quality Control - MonthlySafety interlocksemergencywedge etc Light/ radiation field coincidenceScalesIsocentre positionCross hair positionPTW



Quality Control - MonthlyField size indicatorsDistance measuring indicatorsJaw symmetryLatching of wedges, trays etc.Wedge position (factors etc.)RMI



Quality Control - AnnualDosimetrySafetyMechanical These checks are a scaled down version of the commissioning checks. It is a major QC exercise and is intended to validate the unit for another twelve months.



How to decide on frequency for tests?Likelihood of failureSeverity of the consequences if something goes wrongEase of the test - resources required

This depends on local circumstances!!!



Time requirements for QCExternal beam per megavoltage unitdaily: 30 minutesweekly: 2 hoursmonthly: > 4 hoursannual: 2 days +These are estimates only - a qualified expert must decide on the actual requirements for a particular treatment unitSiemensPrimusLinac



QC for Brachytherapy SourcesThe following QC should be done on receipt of the sources and documentedPhysical/chemical formSource encapsulationRadionuclide distribution and uniformityAutoradiographUniformity of activity amongst seedsVisual inspection of seeds in ribbonsMentor



QC for Brachytherapy SourcesCalibrationDo on receipt and documentIdeal - every sourceLong half-life sources (e.g. Cs 137)AllShort half-life sources (e.g. I 125)If only a few, do them allIf a large number, do a sample e.g. 10%Nucletron



QC for Brachytherapy Sources- multiple seedsSuggested calibration tolerancesIdealmean of batch (3%)Deviation from mean (5%)PracticalReview manufacturers documentation for tolerancesReview ALL the manufacturers documentation



QC for Remote Afterloading Before each treatment dayRoom safety door interlocksLights and alarmsRadiation monitorConsole functionsVisual inspection of source guidesVerify accuracy of ribbon preparationGammasonics



QC for Remote AfterloadingWeeklyAccuracy of source and dummy loadingSource positioningAt each source change or quarterlyCalibrationTimer functionAccuracy of source guides and connectors



QC for Remote AfterloadingAnnualDose calculation algorithmSimulate emergency conditionsVerify source inventory



QC DocumentationForms shall be established to guide the processeasy to follow (even late in the evening after normal treatment has finished)diagrams useful



Examples for forms



Forms are useful for all testsSimple ticks may be sufficientEmpty space forcomments anddrawings



Special equipment and proceduresAll equipment and all procedures should be testedTo design a QC protocol, one needs to fully understand the goals and all steps of the procedureRequires a qualified expertAction levels should be set



A note on action levelsNot too tight - one must be realistic about what can be achievedNot too lax - one must identify unsatisfactory practiceAs the practice improves, the action levels may be tightened



Not only treatment units require QC: SimulatorAppropriate sections from the QC activities for a treatment unitkVp and mAs calibrationImage intensifier quality checksAutomatic exposure control if applicableFilm processor



CT scannerImage qualityScaling and deformationTransfer of dataTransfer of patient (is positioning OK, is couch on CT and linac identical?)Gammex RMI CT test tool



QC for Dosimetry EquipmentLocal standard2 yearly calibrationField instrumentsyearly calibrationLinearityLeakageRecombinationPTW



QC for Measuring EquipmentAutomated scannersPositional accuracyAlignmentAccuracy of data analysisAccessoriesThermometerBarometer



Clinical QCNot only physics and dosimetry must be subject to QC, also clinical management A good way to do this are chart rounds



Chart RoundsRegular review of patientsCan be all patients or randomly selected patientsShould include all patients with unexpected severe complications



Treatment Verification - do not check individual links in the chain but verify the overall outcomeTreatment verification



Treatment VerificationChecks large parts of the treatment chain at once one detects if something is wrong but not necessarily what the problem is.Good strategy when things are mostly OK and within tight tolerancesAllows to follow complex processes



Example for verification:WHO/IAEA photon dose intercomparisonTLD capsulesLevel 1 Intercomparison:Dose in Reference Conditions



Treatment verificationMay be suitable for external auditsShould verify localization of the radiation beam AND the dose deliveredCould include in vivo dosimetry



4. QA and radiation protectionQuality assurance is essential for a functioning system of radiation protectionThe BSS identifies the following areas in particular:Requirements for PracticesSafety of SourcesMedical ExposureOccupational Exposures



QA in medical exposuresPhysical QA as discussed beforeProcess QALeer



QA Program: Arrangements to be required from the licenseeProcedures to establish patient identityProcedures to ensure accordance with prescription by a medical practitionerProcedures to ensure that radiation sources, including equipment can only be purchased from manufacturers and distributors authorized by the Regulatory Authority



Also the radiation protection program itself requires QACheck that the program meets its objectivesDocument improvementsDocument and rectify deficienciesRaise awareness



The cost of QADedicated staff - qualifications, training and numbersEquipment - include allowance for redundancyTime - commissioning, QA, reports, meetings, training



What do we get?Yes, correct - lots of documentation.But there are other benefits...



The benefits of QABenefits for the departmentimproved management systemimproved communicationimproved safetyless duplication and wasteBenefits to patientsoptimized procedurere-assurance



Additional benefitsCredibilityPotential to attract funding (and account for it)Participation in multicenter clinical trialsRegular updates and audits to continue the improvementsPride and confidence of staff



Involvement of AdministrationWithout the support of the Administration the financial resources will not be made availableThe AAPM considers this to be so important that in their Quality Assurance policy they make the very first section Part A: Information for Radiation Oncology Administrators.Educate those who control fundingComprehensive QA for Radiation Oncology, Task Group 40, 1994



But - Beware the Administration Tick in the Box syndrome!Administration will agree with QAThey may even insist upon itWithout education they will not understand what that really means in our environmentMost administrators equate QA with an auditMany simply require the right boxes get ticked so they can be seen to do have done their job - this is not enough...



What do we risk without a Quality Assurance Program?Exeter, UKNew cobalt 60 source installedOver the next 5 months, 207 patients were overdosed by 25% due to an incorrect calibrationContributing factorsCalibration details not recordedLittle documentation or protocols



What do we risk without a Quality Assurance Program? Exeter: Contributing factors (cont.)Reduced staffing levels (money)No independent check of calculationsNo independent check calibrationIt was detected during a Nation wide survey!



Where to get more informationAAPM task group 40: Kutcher GJ, Coia L, Gillin M, Hanson W, Leibel S, Morton RJ, Palta J, Purdy J, Reinstein L, Svensson G, et al. Comprehensive QA for radiation oncology: report of AAPM therapy committee task group 40. Med Phys 1994;21:581-618.AAPM task group 53: Fraas, B. et al. Quality assurance for clinical radiotherapy treatment planning. Med. Phys. 25: 1773-1829; 1997.AAPM task group 56: Nath R.; Anderson L.; Meli J.; Olch A.; Stitt J. A.; Williamson J. Code of practice for brachytherapy physics: report of the AAPM Radiation Therapy Committee Task Group No 56. Med. Phys. 24:1558-98; 1997.ACPSEM Position Paper: Millar M, Cramb J, Das R, Ackerly T, Brown G, Webb D. ACPSEM Position Paper: Recommendations for the safe use of external beams and sealed brachytherapy sources in radiation oncology. Aust.Phys.Eng.Sci.Med. 1997; 20 (Supp): 1-35Institute of Physical Sciences in Medicine. Commissioning and quality assurance of linear accelerators, IPSM report 54. York: IPSM; 1988.International Standards Organisation. Quality management and quality assurance standards. ISO 9000 series.PAN AMERICAN HEALTH ORGANIZATION, Publicacin Cientifica No. 499, Control de Calidad en Radioterapia: Aspectos Clnicos y Fsicos, PAHO, Washington, DC (1986).



WHO (World Health Organisation). Quality Assurance in radiotherapy. Geneva 1988.



SummaryQuality Assurance is an essential part of radiotherapyIt affects all aspects including the radiation protection programThere are many different standards and guidelines for specific QA activities - it requires a qualified expert to choose the most appropriate for a particular centerQA requires and encourages regular external auditsQA is a continuous process - it is aimed at achieving improvements not laying blame.


Any questions?


QuestionPlease give an example for the concept of Continuous Quality Improvement from your practice.



Example just one of manyA centre intends to improve treatment set-up. The measure patient positioning using port films on 20 patients e.g. of the prostate. The random variations are of the order of 8mm and the systematic error on average 9mm.The systematic error could at least partially attributed to different couch sag in simulator and treatment unit. This is reflected in update of the procedures.A repeat test shows that not only the systematic but also the random uncertainty have improved (the latter potentially because of heightened awareness). The smaller random variation allows to pick up other systematic errorsIn addition to this the positive experience leads to the same tests to be done for other treatment sites...



AcknowledgmentLee Collins, Westmead Hospital, SydneyLyn Oliver, Royal North Shore Hospital, Sydney


Part No...., Module No....Lesson NoPart 12: QAActivity: lectureObjectives: To become familiar with the concepts of Quality Assurance as a multidisciplinary activity and its interrelation with radiation protection in radiotherapy.To be familiar with quality assurance procedures as a tool for reviewing and assessing the overall effectiveness of a radiation protection program. To be able to understand the need for and role of specific tests in the context of quality control and be able to identify appropriate national and international protocols for this task To be aware of the need for involvement of professionals in a quality assurance program and for radiation protectionDuration: 3 hoursMaterials and equipment needed: slide projectorReferences: BSS and publications given at the end of the lectureIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe illustration shows the head in the sand mentality. Quality assurance enables us to face reality...IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis is a very important slide - the context of medical exposure is relevant for the whole part 12.The second point relates to a meta QA. QA does not only apply to radiotherapy activities but also to radiation protection and the lecturer could mention that in this context the QA activities also will need a check: are they effective in enhancing radiation protection?IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoQuality assurance is given a high importance in the BSS context - it is part of the managerial requirements.The lecturer should point out that this fact (managerial requirement) does not imply that QA is a top down process (workers wait until management instigates a QA program). The idea of QA is that everyone at all levels MUST be actively involved.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe following section always presents quotes from BSS and then tries to relate this back to radiotherapy practice. The lecturer is encouraged to use her/his own experience to expand on this.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoMore references given at the end of the lecture and also part of the handout.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoMore on this in section 3 of the lectureIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoCommissioning data provides the basis of the tests chosen (what appears to be most in need of testing?) AND the benchmark quantitative data.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer may want to point out that a treatment record could also be electronically, as it is the case with many record and verify systems. However, in practice a paper record is just as good.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe slide illustrates the fact that ISO standards are often incorporated into national standards - this makes them legally binding locally.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe second message - while obvious - is important. The cost of a major accident exceeds the cost to instigate a good QA system by far.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer can introduce this by asking: QA is good, but HOW are we going about to commence itIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis slide can be included if time permits - it is relevant particular if the participants are administrators or medical physicists who would instigate the implementation.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThese points are discussed in more detail in the following slidesIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoAn important slide - the lecturer should take some time to take the participants through it.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoRepresent the department means: should have representation form all major professional groups in the department. It also indicates that this includes all levels of staff (eg unionized, managerial, part time).IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe last point is only an example. It is likely that every clinic will adopt an action level for output - however, the actual level can be different (compare next slide) and must be agreed on locally.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe topic of action levels will be revisited in part 18 of the course.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoTerms of referecne are discussed in more detail in part 18 of the course. There also an example for a radiation safety committee will be developed.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer should point out that the QA team is different from the QA committee. The QA team is responsible for performing the QA activities.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoEuropean Society for Therapeutic Radiology and Oncology (ESTRO) Advisory Report to the Commission of the European Union for the 'Europe Against Cancer Programme'. Quality Assurance in radiotherapy. Radiother. Oncol. 35: 61-73; 1995.

IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe first two examples are dose verification services.The calibration of a radiation beam is checked using TLDs. More information on this was given in part 10, lecture 2 on dosimetry. IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis is a very important point - quality assurance is never complete. It is an on-going process which must take into account new information and new equipment (hardware and software) as it becomes available.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe no parking symbol illustrates the fact that one cannot stand still in QA.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe last two points are important: openness must be encouraged. Any problem becomes worse if it is not addressed. IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer can point out that it is beyond the scope of the course to introduce any of the QA protocols in much detail. Here, the general ideas shall be dealt with, the protocols shown here provide guidance on the set-up of a QA program which must be specific for the circumstances a radiotherapy department is in. The references shown are:Institute of Physical Sciences in Medicine. Commissioning and quality assurance of linear accelerators, IPSM report 54. York: IPSM; 1988.AAPM task group 40: Kutcher GJ, Coia L, Gillin M, Hanson W, Leibel S, Morton RJ, Palta J, Purdy J, Reinstein L, Svensson G, et al. Comprehensive QA for radiation oncology: report of AAPM therapy committee task group 40. Med Phys 1994;21:581-618.International Atomic Energy Agency. Design and implementation of a radiotherapy programme: clinical, medical physics, radiation protection and safety aspects. IAEA-TECDOC 1040, Vienna 1998. Not shown but equally important is:WHO (World Health Organisation). Quality Assurance in radiotherapy. Geneva 1988.Participants should have access to all of them.

IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis is an interesting article which is mentioned as it focuses on the point that QA is not just required for hardware but also for information flow.The complexity of the information flow chain in radiotherapy can be enormous (in particular in advanced treatment such as IMRT). It is essential to ensure that all transmission of information is accurate. Record and verify systems (such as Varis or Impac) are useful in this context.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecture can use slides from part 10.3 to complement the present lecture. This may be essential if part 10 of the course is abbreviated. For this purpose, QA is dealt with in a separate slide series X.3.CIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer must point out that the activities suggested on the following slides are suggestions only. The same applies for the practical exercises.They must be modified and agreed upon locally.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoA slide currently hidden but included in the handout for reference.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThese checks are usually quickly done.The picture shows a device for daily output consistency checks - it is a based on a sealed ionization chamber (no temperature/pressure correction necessary) and features a large read-out which can be seen through the patient monitoring video system.

IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe test tool (= jig) allows to check field size for different collimator and gantry angles, allows to verify the optical distance indicator for different gantry angles and allows to perform a check of all lasers for patient alignment. Tests with a similar tool will be part of a practical exercise.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe laser must be horizontal/vertical at least for distances which are compatible with typical patient size.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe couch movements are often used for patient positioning eg when lining up the patient to an anatomical landmark or tattoo and then shifting the patient x cm longitudinally.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoPart of handout slides - the participants are encouraged to produce their own chart in a practical exercise.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoBoth % depth dose and flatness symmetry can verify the radiation energy. Flatness is usually a rather sensitive test as the flattening filter is energy sensitive.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoShown is a tool for cross hair alignment checksIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoShown is a tool to verify field size and distance indicatorsIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIn particular for a badly performing unit, or a unit which has failed often on previous tests, one may need to spend considerably longer time.The picture is just an illustration.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis slide switches the considerations form external beam to brachytherapy.Shown is a Mentor 125-I seed.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoShown is a radiation monitor with a hand held probeIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe form shown is a good example - it is clearly laid out and uses graphics. A brief graphical description of the test (cross hair centre variation with gantry position) is shown. Most importantly, the bottom line is: Action required? IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoConstantinou C. Protocol and procedures for quality assurance of linear accelerators. Brockton: Constantinou; 1994. Available from Medical Physics Publishing, Madison.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoMore information on these tests is given in the companion course of diagnostic radiologyIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe test tool shown has different sections:The front section which is visible checks alignment and CT numbers for 4 test objects. Other sections check spatial and contrast resolution.The whole phantom is made from water equivalent material.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe illustration shows a PTW electrometer and a pin-point chamberIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoBarometer can be checked against a meteorological station close - however, care must be taken that the correct units are used and appropriate corrections eg for altitude are applied.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoExplained in more detail on the next slideIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoBy doing this chart rounds not only can improve clinical practice and help to develop good local protocols, it is also possible that the round pick up physical problems such as the ones discussed in the next part of the course (13) on accidents.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoExplained more in the next slideVerification - as test of a large part of a chain at once - is an additional QA check suitable for audits. It does NOT replace QA activities for individual steps.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe lecturer can point out that these very points make verification as defined here highly suitable for external audits.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoMore details on this are provided in part 10 lecture 2 of the course.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoQA in medical exposures is the main topic of the present lecture.Requirements for practices are covered throughout the course while safety of sources and occupational exposure have their own parts (15 and 8, receptively) in the courseIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIt is not necessary for the participants to understand the flow chart in detail. It is from a publication by W Leer. Important is to show how a flow chart can map a process. Protocols are developed to guide the practice within and QA activities must check that the process achieves its objective.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThis is part of a critical approach. IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoRedundancy in the context of the second point means there should be a second piece of equipment which can perform the same (or at least a similar) function as the equipment in use. This allows cross checks and ensures the availability of a back-up.The bottom line for many people - it is important to discuss costs/benefit also for QA. It is hoped that the following slides can be used to stimulate discussion amongst the participants. IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoPrevention of accidents is not mentioned here on purpose even if it is a very important outcome of QA. It would be excellent if the participants note this (prompted or un-prompted by the lecturer).Accidents are covered in the last slides of the talk.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIt should not be difficult to convince management about the need for QA. It helps everyone. Typically only the expenditures and resources necessary to perform it are a matter of discussion. This can be resolved by a scientific approach which assesses QA needs and resources and prioritize the activities needed.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoPart of the handout - no need to be able to read or copy this here.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoA final referenceIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoOther features could be added as required locally

IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoThe question should stimulate discussion using the participants own experience. As CQI is the topic, participants can bring in success stories which will help to re-enforce the message of QA as something positive.

If no examples are forthcoming, the lecturer could illustrate the concept by the following example:A centre intends to improve treatment set-up. The measure patient positioning using port films on 20 patients eg of the prostate. The random variations are of the order of 8mm and the systematic error on average 9mm.The systematic error could at least partially attributed to different couch sag in simulator and treatment unit. This is reflected in update procedures.A repeat test show that not only the systematic but also the random uncertainty have improved (the latter potentially because of heightened awareness). The smaller random variation allows to pick up other systematic errorsIn addition to this the positive experience leads to the same tests to be done for other treatment sites...IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson Nothis is a true story form the authors experience in the case of prostate cancer patients set-up.IIAEA Training Material: Radiation Protection in RadiotherapyPart No...., Module No....Lesson NoIIAEA Training Material: Radiation Protection in Radiotherapy

Radiation Protection in Radiotherapy

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