part viii:medical exposures in radiotherapy acceptance testing & quality assurance lecture 8 :...
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Part VIII:Medical Exposures in Part VIII:Medical Exposures in RadiotherapyRadiotherapy
Lecture 8 : Acceptance testing & Quality Acceptance testing & Quality Assurance Assurance
IAEA Post Graduate Educational Course on Radiation Protection and Safe Use of Radiation Sources
Module 4. Quality Assurance
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 2
ObjectiveObjective• To appreciate the need for Quality assurance and To appreciate the need for Quality assurance and
Quality control in Radiation therapyQuality control in Radiation therapy• To familiarize with the procedures for quality control To familiarize with the procedures for quality control
at various stages of Radiation therapy processat various stages of Radiation therapy process• To understand the basic quality control tests for To understand the basic quality control tests for
Simulator, Treatment planning system, dose Simulator, Treatment planning system, dose delivery, and teletherapy equipmentdelivery, and teletherapy equipment
• To understand & appreciate the requirements of To understand & appreciate the requirements of routine quality assurance procedures for LDR and routine quality assurance procedures for LDR and HDR remote after loading units.HDR remote after loading units.
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 3
What is Quality?What is Quality?
• The quality can be defined as ‘the totality of features The quality can be defined as ‘the totality of features of a product or service that bears its ability to satisfy of a product or service that bears its ability to satisfy given needs’given needs’
• quality relates to quality relates to – Fitness for useFitness for use– Fitness for purposeFitness for purpose– Quality refers to certain standards and the ways Quality refers to certain standards and the ways
and means by which those standards are and means by which those standards are achieved, maintained and improved uponachieved, maintained and improved upon
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 4
What is Quality system?What is Quality system?
• Quality system is the total QA process for the Quality system is the total QA process for the total organization or for specific functional total organization or for specific functional areas within the organization.areas within the organization.
• Purpose : To provide management control Purpose : To provide management control over the activities that affect the quality of over the activities that affect the quality of service deliveredservice delivered
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 5
What is meant by Quality What is meant by Quality Assurance? Assurance?
• Quality assurance is ‘ all those planned and systematic Quality assurance is ‘ all those planned and systematic actions necessary to provide adequate confidence that a actions necessary to provide adequate confidence that a product or a service will satisfy given requirements for product or a service will satisfy given requirements for quality’quality’
• In radiation Therapy QA is ‘ all those procedures that In radiation Therapy QA is ‘ all those procedures that ensure consistency of the medical prescription and the ensure consistency of the medical prescription and the safe fulfillment of the prescription as regards to the safe fulfillment of the prescription as regards to the target volume, together with minimal dose to normal target volume, together with minimal dose to normal tissue, minimal exposure of personal, and adequate tissue, minimal exposure of personal, and adequate patient monitoring aimed at determining the end result of patient monitoring aimed at determining the end result of treatment’treatment’
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 6
What is Quality Control?What is Quality Control?
• Quality control is the ‘regulatory process Quality control is the ‘regulatory process through which the actual quality performance through which the actual quality performance is measured compared to existing standards is measured compared to existing standards and finally the actions necessary to keep or and finally the actions necessary to keep or regain conformance with the standards’ regain conformance with the standards’
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 7
What are the components of Quality What are the components of Quality control in Radiation oncology?control in Radiation oncology?
• Specification of the product or processSpecification of the product or process– Defined prior to purchase or Defined prior to purchase or – The initial standards measured during The initial standards measured during
commissioningcommissioning• Measurement of PerformanceMeasurement of Performance• Inspection or measurement or service of the product Inspection or measurement or service of the product
to determine conformance to specificationto determine conformance to specification• Feedback to ensure that the measure has met the Feedback to ensure that the measure has met the
specification or device to regain the standardspecification or device to regain the standard
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 8
QA and QCQA and QC
• Quality Assurance is the overall process Quality Assurance is the overall process which is supported by Quality Control which is supported by Quality Control activitiesactivities
• Quality Control describes the actual Quality Control describes the actual mechanisms and procedures by which one mechanisms and procedures by which one can assure qualitycan assure quality
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 9
QA Cost-BenefitQA Cost-Benefit
• Benefit of QA comes at a costBenefit of QA comes at a cost• Very little QA effort Very little benefitVery little QA effort Very little benefit• Too much QA effort does not increase the benefitToo much QA effort does not increase the benefit• Need to optimize the QA effort - Balance between to Need to optimize the QA effort - Balance between to
little and too muchlittle and too much
Svensson GK
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 10
A Comprehensive QA Program A Comprehensive QA Program typically comprises oftypically comprises of
• Quality Assurance CommitteeQuality Assurance Committee• Policies and Procedures ManualPolicies and Procedures Manual• Quality Assurance teamQuality Assurance team• Quality auditQuality audit• ResourcesResources
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 11
Policies and ProceduresPolicies and ProceduresRecommended steps in procedures developmentRecommended steps in procedures development• Review current practiceReview current practice• Analyze current practiceAnalyze current practice• Develop & Release a draft procedureDevelop & Release a draft procedure• Review commentsReview comments• Revise and issue procedure for acceptanceRevise and issue procedure for acceptance• Obtain approvalObtain approval• Issue for useIssue for use• ImplementImplement• Monitor and reviewMonitor and review
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 12
What is Quality Audit? What is Quality Audit?
• Quality audit consists of a systematic and Quality audit consists of a systematic and independent (preferably external) review independent (preferably external) review (examination and evaluation) of the QA system(examination and evaluation) of the QA system– To determine whether the system is To determine whether the system is
implemented effectively andimplemented effectively and– Whether the activities and results produce Whether the activities and results produce
the required end-point complying with the required end-point complying with predetermined quality standards.predetermined quality standards.
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 13
Quality AuditQuality Audit
• Ideally performed by someone outside of the Ideally performed by someone outside of the organizationorganization
• ExamplesExamples– IAEA/WHO TLD program for check of dose IAEA/WHO TLD program for check of dose
in therapy unitsin therapy units– EQUAL program in EuropeEQUAL program in Europe– Audits of clinical trials participationAudits of clinical trials participation
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 14
Quality AuditQuality Audit• ““A systematic and independent examination A systematic and independent examination
and evaluation to determine whether quality and evaluation to determine whether quality activities and results comply with planned activities and results comply with planned arrangements and whether the arrangements arrangements and whether the arrangements are implemented effectively and are suitable to are implemented effectively and are suitable to achieve the objectives.”achieve the objectives.”
““Quality assurance in radiotherapy.”, Radiother. Oncol., 1995Quality assurance in radiotherapy.”, Radiother. Oncol., 1995
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 15
What are Quality Standards?What are Quality Standards?
• Quality standards are the criteria against which the Quality standards are the criteria against which the quality of any form of activity can be assessed.quality of any form of activity can be assessed.– Example : The field size measured should be Example : The field size measured should be
within 1mmwithin 1mm• While developing QA standards one should considerWhile developing QA standards one should consider
– Ease of useEase of use– DocumentationDocumentation– Frequency of faultsFrequency of faults– Cost Versus reliabilityCost Versus reliability
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 16
Quality SystemQuality System
• PurposePurpose– To provide management control over the To provide management control over the
activities that affect the quality of service activities that affect the quality of service delivered.delivered.
• People are a key ingredient for the quality People are a key ingredient for the quality service and the operational quality controlservice and the operational quality control
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 17
What is ISO 9000?What is ISO 9000?
• The International organization for The International organization for Standardization (ISO) has developed a Standardization (ISO) has developed a series of standards and guideline series of standards and guideline documents that aid the development of documents that aid the development of quality managementquality management
• ISO 9000 in itself is not a standard but ISO 9000 in itself is not a standard but generic term applying to a series of generic term applying to a series of standards and accompanying guidelinesstandards and accompanying guidelines
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 18
Quality Assurance (QA)Quality Assurance (QA)
• ISO 9000: “all those planned and systematic ISO 9000: “all those planned and systematic actions necessary to provide adequate actions necessary to provide adequate confidence that a product or service will confidence that a product or service will satisfy given requirements for quality”satisfy given requirements for quality”
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 19
Quality Control (QC)Quality Control (QC)
• ISO 9000: “the regulatory process through ISO 9000: “the regulatory process through which the actual quality performance is which the actual quality performance is measured, compared to existing standards measured, compared to existing standards and finally the actions necessary to keep or and finally the actions necessary to keep or regain the standards”regain the standards”
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 20
Total Quality Management (TQM)Total Quality Management (TQM)
• That aspect of overall management function that That aspect of overall management function that determines and implements the quality policy, and , as determines and implements the quality policy, and , as such, is the responsibility of top management”such, is the responsibility of top management”
• Leadership is the most important ingredient in the TQM Leadership is the most important ingredient in the TQM philosophyphilosophy
Quality Assurance does not stop Quality Assurance does not stop here!here!
The Quality Assurance Committee and The Quality Assurance Committee and the Quality Assurance team must the Quality Assurance team must
continuously monitor new information continuously monitor new information and implement this in their proceduresand implement this in their procedures
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 22
Continuous Quality ImprovementContinuous Quality Improvement
• Dynamic way to perform with a determination to Dynamic way to perform with a determination to improve in all areas”improve in all areas”– continuous, on-goingcontinuous, on-going
• CQI - many other acronyms are available for thisCQI - many other acronyms are available for this• Part of virtually all QA systemsPart of virtually all QA systems• Improved methods on cancer patient management Improved methods on cancer patient management
are documented in clinical trial reports.are documented in clinical trial reports.
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 23
Continuous Quality ImprovementContinuous Quality Improvement
• Quality assurance protocols are continuously under Quality assurance protocols are continuously under development in many countriesdevelopment in many countries
• Regular Quality Assurance meeting for all members Regular Quality Assurance meeting for all members of a Sectionof a Section
• Continuing education - lectures, workshops, journal Continuing education - lectures, workshops, journal clubs and must be available for all staffclubs and must be available for all staff
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 24
QA is not policing but it is perfecting the QA is not policing but it is perfecting the processprocess
• It is essential in a QA program that all It is essential in a QA program that all staff feel free to report errorsstaff feel free to report errors
• A non threatening environment must A non threatening environment must existexist
• Reward honesty with encouragementReward honesty with encouragement• Education is the key, not punishmentEducation is the key, not punishment
And finally QA is not a threat but an opportunity
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 25
QC in Radiation OncologyQC in Radiation Oncology
• Specification of product or processSpecification of product or process• Measurement of performanceMeasurement of performance• Comparison of measurement to specificationComparison of measurement to specification• Feedback to ensure that measurement has Feedback to ensure that measurement has
met specification or adjustments to regain the met specification or adjustments to regain the result within specificationresult within specification
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 26
Why Quality system in Radiation Why Quality system in Radiation Oncology?Oncology?
• A Quality system raises morale of personnelA Quality system raises morale of personnel• A quality system increases efficiencyA quality system increases efficiency• QA reduces the likelihood of accidents and QA reduces the likelihood of accidents and
errorserrors• QA reduces the chance of litigationQA reduces the chance of litigation
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 27
QA in Radiation TherapyQA in Radiation Therapy
• Every step in Radiation therapy from diagnosis to Every step in Radiation therapy from diagnosis to treatment should have a proper quality control treatment should have a proper quality control system in place. system in place.
• Radiation therapy involves use of equipment form Radiation therapy involves use of equipment form diagnosis to treatment and periodic QA program diagnosis to treatment and periodic QA program should be available for testing the performance of should be available for testing the performance of these unitsthese units
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 28
Quality Control in radiotherapyQuality Control in radiotherapy
• Many documents exist that specify what QA activities Many documents exist that specify what QA activities should be performed in radiotherapy…should be performed in radiotherapy…
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 29
What comprises the QA in Radiation What comprises the QA in Radiation TherapyTherapy
• Quality Assurance in Radiation Therapy involvesQuality Assurance in Radiation Therapy involves1.1. Treatment planningTreatment planning
– Simulator, compensators, customized Simulator, compensators, customized shielding, castsshielding, casts
2.2. Clinical DosimetryClinical Dosimetry• Water phantom system, Local standard, Water phantom system, Local standard,
electrometer electrometer • Treatment time calculationTreatment time calculation
3.3. Treatment: Treatment: • Treatment unit, treatment setup Treatment unit, treatment setup
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 30
What is the frequency of the QA What is the frequency of the QA checks?checks?
• Frequency of the QA checks in Radiotherapy Frequency of the QA checks in Radiotherapy treatment varies at different levelstreatment varies at different levels
• Some areSome are– daily,daily,– weeklyweekly – monthlymonthly – yearlyyearly– depending on the performancedepending on the performance
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 31
Quality assurance at Treatment Quality assurance at Treatment Planning stagePlanning stage
QA of SimulatorQA of Simulator
QA of Simulator consists of series of Quality control QA of Simulator consists of series of Quality control tests, which can be divided astests, which can be divided as
1.1. Mechanical and Optical parameters: Mechanical and Optical parameters:
2.2. X-ray beam parameters (X-ray beam parameters (Image forming system)Image forming system)
3.3. Performance of Image IntensifierPerformance of Image Intensifier
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 32
Mechanical and Optical parameters:Mechanical and Optical parameters:
• Verification of Field SizeVerification of Field Size • Isocentre checkIsocentre check• Check on radiation field – light field congruenceCheck on radiation field – light field congruence
Star shot – isocentre check Optical – Radiation Field alignment
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 33
X-ray beam parameters X-ray beam parameters ((Image forming system)Image forming system)
• Verification of kV and mAVerification of kV and mA• Consistency of x-ray outputConsistency of x-ray output• Timer checkTimer check• Focal spot sizeFocal spot size• Tube leakage testTube leakage test
mAs & KVp meter
X-ray output
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 34
X-ray beam parameters X-ray beam parameters ((Image forming system)Image forming system)
• Focal spot sizeFocal spot size• Verification of kV and mAVerification of kV and mA• Consistency of x-ray outputConsistency of x-ray output• Timer checkTimer check• Tube leakage testTube leakage test
Verification of focal spot size
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 35
Performance of Image IntensifierPerformance of Image Intensifier
• ResolutionResolution , , Low contrast performanceLow contrast performance
Resolution check of Image intensifier Contrast check – the Leeds disc
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 36
What are the Safety tests on What are the Safety tests on Simulator?Simulator?
Test Test
1.1. Door InterlockDoor Interlock
2.2. Motion enable/disable Motion enable/disable switchesswitches
3.3. Warning LightsWarning Lights
4.4. Emergency offEmergency off
5.5. Collision avoidanceCollision avoidance
Frequency of TestsFrequency of Tests
DailyDaily
DailyDaily
DailyDaily
DailyDaily
DailyDaily
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 37
What are the Daily quality control What are the Daily quality control tests on a simulator?tests on a simulator?
TestTest1.1. Optical checksOptical checks
Localizing lasersLocalizing lasersDistance indicator (SAD)Distance indicator (SAD)
2.2. Mechanical checksMechanical checksCross hair centeringCross hair centeringBlock tray centeringBlock tray centeringField size indicatorField size indicator
3.3. Safety checksSafety checksDoor interlockDoor interlockMotion & Warning lightsMotion & Warning lights
ToleranceTolerance
2mm2mm
2mm2mm
2mm2mm
2mm2mm
1mm per edge1mm per edge
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 38
Listing of Listing of Simulator QASimulator QA
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 39
Quality assurance of Treatment Quality assurance of Treatment planningplanning
Components of Quality assurance for treatment Components of Quality assurance for treatment planningplanning
• Training of staffTraining of staff– Understanding the algorithmUnderstanding the algorithm– Understanding the input requirementsUnderstanding the input requirements– Verification of beam dataVerification of beam data
• Reproducibility testsReproducibility tests• In vitro/vivo dosimetryIn vitro/vivo dosimetry
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 40
Quality control checks for planning Quality control checks for planning systemsystem
• HardwareHardware– Digitizer Digitizer – Plotter Plotter
– CT interface for image CT interface for image
transfertransfer • External beam dataExternal beam data
– Data set Data set – Reference Field size planReference Field size plan– Monitor UnitsMonitor Units
Frequency of checkFrequency of checkweekly checkweekly check
weekly checkweekly check
System turn onSystem turn on
semi-annuallysemi-annually
semi-annuallysemi-annually
Each patientEach patient
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 41
In Vitro / in vivo dosimetry checksIn Vitro / in vivo dosimetry checks
• In vitro dosimetry with In vitro dosimetry with Anthropomorphic phantom Anthropomorphic phantom (Rando)(Rando)
• This phantom could be CT This phantom could be CT scanned and planned like scanned and planned like patient patient
• Phantom could be loaded Phantom could be loaded with TLD and treatemnt plan with TLD and treatemnt plan could be verifiedcould be verified
Rando Phantom
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 42
In vivo dosimetryIn vivo dosimetry
• Verification of dose Verification of dose delivereddelivered
• Dose to Critical organs – Dose to Critical organs – eyes, gonads or fetuseyes, gonads or fetus
• Exit dosimetryExit dosimetry• DetectorsDetectors
– Diode, MOS-FET,Diode, MOS-FET,– TLDTLD
TLD readerMOSFET detectors
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 43
Quality assurance of Teletherapy unit Quality assurance of Teletherapy unit
(Telecobalt & Linear accelrator)(Telecobalt & Linear accelrator)• Mechanical movementsMechanical movements• Radiation field alignmentRadiation field alignment• Radiation ON indicatorsRadiation ON indicators• Source ON/OFF Source ON/OFF
mechanism (Telecobalt)mechanism (Telecobalt)• Safety interlocksSafety interlocks
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 44
Mechanical checks on a teletherapy Mechanical checks on a teletherapy unit unit
• Rotational movementsRotational movementsVerification of mechanical vs digital indicatorVerification of mechanical vs digital indicator
– Gantry angle indicatorGantry angle indicator– Couch position indicatorCouch position indicator– Collimator angle indicatorCollimator angle indicator
• Field Size Field Size • Isocentre checkIsocentre check
Mechanical position indicator
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 45
Field size checkField size check
• Verification of Optical field with field size Verification of Optical field with field size indicator indicator (maximum tolerance 1mm on all sides)(maximum tolerance 1mm on all sides)
• verification of field size forverification of field size for
Various gantry anglesVarious gantry angles
Field size verification plates
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 46
Radiation / Light-Field Congruence Radiation / Light-Field Congruence
• Optical field used to setup Optical field used to setup patient and the radiation filed patient and the radiation filed should matchshould match
• Error in radiation and light field Error in radiation and light field congruence could lead to congruence could lead to geographical miss of the geographical miss of the tumourtumour
• Should be verified weeklyShould be verified weekly
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 47
Isocentre checkIsocentre check
• Isocentre verification forIsocentre verification for– GantryGantry– CouchCouch– CollimatorCollimator
• Wandering of Crosswire center for 360Wandering of Crosswire center for 360oo rotation rotation
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 48
Verification of IsocentreVerification of Isocentre
• Verification of Isocentre wandering for gantryVerification of Isocentre wandering for gantry
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 49
Verification of SSD indicatorVerification of SSD indicator
• Optical SSD indicator to be verified withOptical SSD indicator to be verified with
Mechanical front pointers for various SSDsMechanical front pointers for various SSDs
Front pointer
Front pointers for Different SSDs
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 50
Verification of Laser alignment Verification of Laser alignment
• Isocentre alignment to be checkedIsocentre alignment to be checked• Wrong indication of isocentre by lasers will Wrong indication of isocentre by lasers will
result in geographical missresult in geographical miss
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 51
QA of Telecobalt Safety featuresQA of Telecobalt Safety features
• Indicator ON lightsIndicator ON lights• Radiation area monitor – audio and visible indicators Radiation area monitor – audio and visible indicators
function function • Source ON Mechanical indicator on the Source ON Mechanical indicator on the
treatment unittreatment unit• Source ON indicator light at the doorSource ON indicator light at the door• Function of Emergency OFF switchFunction of Emergency OFF switch
Radiation area monitor
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 52
Radiation beam check – Telecobalt Radiation beam check – Telecobalt unitunit
• Radiation output for cobalt – to be checked Radiation output for cobalt – to be checked once a month for cobalt once a month for cobalt
• Energy check – not required for telecobaltEnergy check – not required for telecobalt• Timer to be checked dailyTimer to be checked daily
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 53
QA QA work work sheet sheet
for for CobaCoba
ltlt
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 54
Radiation Output & Energy CheckRadiation Output & Energy Check(Linear accelerator)(Linear accelerator)
• Radiation output for Linac – to Radiation output for Linac – to be checked daily for both be checked daily for both photon and electron beamsphoton and electron beams
• Energy check – to be done Energy check – to be done dailydaily
• Index for energy – TMRIndex for energy – TMR20/1020/10
• Radiation of dose at 20cm to Radiation of dose at 20cm to dose at 10cm at isocentric dose at 10cm at isocentric conditioncondition TMRTMR20/1020/10
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 55
Radiation beam check for LinacRadiation beam check for Linac
• Radiation beam flatness Radiation beam flatness • Beam symmetryBeam symmetry• PenumbraPenumbra• The above should be The above should be
checked once in six checked once in six monthsmonths
Beam profile - flatness
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 56
• QA work sheet forQA work sheet for
Linear acceleratorLinear accelerator
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 57
QA for Remote afterloading unit in QA for Remote afterloading unit in BrachytherapyBrachytherapy
• Radiation safety checksRadiation safety checks• Verification of source integrityVerification of source integrity• Verification of source position (dwell position)Verification of source position (dwell position)• Verification of dwell timeVerification of dwell time
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 58
Verification of source positionVerification of source position
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 59
Dwell position checkDwell position check
• Auto-radiograph to verify Auto-radiograph to verify the dwell position of the the dwell position of the HDR sourcesHDR sources
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 60
LDR source position check LDR source position check
QA kit for LDR auto-radiograph Auto-radiographLDR unit
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 61
SummarySummary
• Quality assurance is an important component Quality assurance is an important component of Radiotheray processof Radiotheray process
• QA procedures and policies must be setup QA procedures and policies must be setup and implemented at every stepand implemented at every step
• Proper QA tools should be usedProper QA tools should be used
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 62
SummarySummary
• QA has to be performed periodically for all the QA has to be performed periodically for all the steps involved in Radiotherapy.steps involved in Radiotherapy.
• QA should include mechanical movements, QA should include mechanical movements, radiation beam check and also radiation radiation beam check and also radiation safety checkssafety checks
• In the case of Treatment planning system QA In the case of Treatment planning system QA should include verification of input data and should include verification of input data and algorithm.algorithm.
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 63
QuestionsQuestions
• What is Quality Control?What is Quality Control?• What is Quality Assurance?What is Quality Assurance?• Why QA of simulator is a must?Why QA of simulator is a must?• What are the parameters to be checked for What are the parameters to be checked for
QA of Treatment planning systemQA of Treatment planning system• How often the output of Telecobalt unit has to How often the output of Telecobalt unit has to
be determined?be determined?
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 64
QuestionsQuestions
• What is radiation field congruence check?What is radiation field congruence check?• What additional checks on Radiation beam to What additional checks on Radiation beam to
be carried out for linac over cobalt units?be carried out for linac over cobalt units?• What is an auto-radiograph?What is an auto-radiograph?• How is an auto-radiograph useful as QA tool?How is an auto-radiograph useful as QA tool?
Part VIII.4.8 Acceptance testing & Quality Assurance Acceptance testing & Quality Assurance Slide 65
ReferencesReferences• ‘‘The Modern Technology of Radiation Oncology’ The Modern Technology of Radiation Oncology’
– Editor Jacob Van DykEditor Jacob Van Dyk
• The Physics of Radiation Therapy III EditionThe Physics of Radiation Therapy III Edition
– Faiz M KhanFaiz M Khan
• ‘Acceptance testing and commissioning of Ximatron Radiotherapy Simulator’ - Journal of Medical Physics, Vol.26, No.2
– B Paul Ravindran et al
• Design and implementation of a radiotherapy programme: clinical, medical physics, radiation protection and safety aspects - IAEA Tec Doc 1040