Linear Accelerator Daily QA1,2 Procedure Non-IMRT IMRT SRS/SBRT
Dosimetry
X-ray output constancy (all energies) 3%
Electron output constancy* 3%
Mechanical
Laser localization 2 mm 1.5 mm 1 mm
Optical Distance Indicator (ODI) at isocenter 2 mm 2 mm 2 mm
Collimator size indicator 2 mm 2 mm 1 mm
Safety
Door Interlock Functional
Door closing safety Functional
Audiovisual monitors Functional
Stereotactic interlocks NA NA Functional
Radiation area monitor (if used) Functional
Beam on indicator Functional
*Electron output constancy only needs to be performed weekly except for machines with unique e-monitoring requiring daily checks
Linear Accelerator Monthly QA1,2
Procedure Non-IMRT IMRT SRS/SBRT
Dosimetry
X-ray output constancy
Electron output constancy 2%
Backup monitor chamber constancy
Typical dose rate output constancy NA 2% IMRT dose rate 2% stereo dose rate, MU
Photon beam profile constancy 1%
Electron beam profile constancy 1%
Electron beam energy constancy 2%/2 mm
Mechanical
Light/radiation field coincidence 2 mm or 1% on a side
Light/radiation field coincidence (asymmetric) 1 mm or 1% on a side
Distance check-lasers with front pointer 1 mm
Gantry/Collimator angle indicators* 1.0°
Accessory trays 2 mm
Jaw position indicators (symmetric) 2 mm
Jaw position indicators (asymmetric) 1 mm
Cross-hair centering 1 mm
Treatment couch position indicators 2 mm/1° 2 mm/1° 1 mm/0.5°
Wedge placement accuracy 2 mm
Compensator placement accuracy 1 mm
Latching of wedges, blocking tray Functional
Localizing lasers ± 2 mm ± 1 mm ˂ ± 1 mm
Safety
Laser guard-interlock test Functional
Respiratory Gating
Beam output constancy 2%
Phase, amplitude beam control Functional
In-room respiratory monitor system Functional
Gating interlock Functional
*at cardinal angles
Linear Accelerator Annual QA1,2
Procedure Non-IMRT IMRT SRS/SBRT
Dosimetry
X-ray flatness change from baseline 1%
X-ray symmetry change from baseline ±1%
Electron flatness change from baseline 1%
Electron symmetry change from baseline ±1%
SRS arc rotation mode - 0.5-10 MU/deg NA NA
MU vs delivered: 1.0 MU or 2% (whichever is
greater) Gantry arc set vs
delivered: 1.0° or 2% (whichever is greater)
X-ray/electron output calibration (TG-51) ±1% (Absolute)
Spot check of field size dependent output factors for x-ray (2 or more)
2% for FS˂4 x 4cm2
1% for FS≥ 4 x 4cm2
Output factors for electron applicators (spot check for one applicator/energy)
±2% from baseline
X-ray beam quality (PDD10 or TMR2010) ±1% from baseline
Electron beam quality (R50) ±1 mm
Physical wedge transmission factor constancy
±2%
X-ray monitor unit linearity (output constancy)
2%≥ 5MU ±5% (2-4 MU)
±2% ≥ 5 MU ±5% (2-4 MU)
±2% ≥ 5 MU
Electron monitor unit linearity (output constancy)
±2%≥ 5 MU
X-ray output constancy vs dose rate ±2% from baseline
X-ray output constancy vs gantry angle ±1% from baseline
Electron output constancy vs gantry angle
±1% from baseline
Electron and x-ray off-axis factor constancy vs gantry angle
±1% from baseline
Arc mode (expected MU, degrees) ±1% from baseline
TBI/TSET Mode Functional
PDD or TMR and OAF constancy 1% (TBI) or 1 mm PDD shift (TSET)
from baseline
TBI/TSET output calibration 2% from baseline
TBI/TSET accessories 2% from baseline
Mechanical
Collimator rotation isocenter ±1 mm from
baseline
Gantry rotation isocenter ±1 mm from
baseline
Couch rotation isocenter ±1 mm from
baseline
Electron applicator interlocks Functional
Coincidence of radiation and mechanical isocenter
±2 mm from baseline
±2 mm from baseline
±1 mm from baseline
Table top sag 2 mm from baseline
Table angle 1°
Table travel maximum range in movement - all directions
±2 mm
Stereotactic accessories, lockouts, etc. NA NA Functional
Safety
Follow manufacturer's test procedures Functional
Respiratory Gating
Beam energy constancy 2%
Temporal accuracy of phase/amplitude gate on
100 ms of expected
Calibration of surrogate for respiratory phase/amplitude
100 ms of expected
Interlock testing Functional
Imaging Daily QA1 Procedure Non-SRS/SBRT SRS/SBRT
Planar kV and MV (EPID) Imaging
Collison interlocks Functional Functional
Positioning/repositioning ≤ 2 mm ≤ 1 mm
Imaging and treatment coordinate coincidence (single gantry angle) ≤ 2 mm ≤ 1 mm
Cone-beam CT (kV and MV)
Collison interlocks Functional Functional
Positioning, repositioning ≤ 1 mm ≤ 1 mm
Imaging and treatment coordinate coincidence ≤ 2 mm ≤ 1 mm
Imaging Monthly QA1 Procedure Non-SRS/SBRT SRS/SBRT
Planar MV Imaging (EPID) Imaging and treatment coordinate coincidence (four cardinal angles)
≤ 2 mm ≤ 1 mm
Scaling ≤ 2 mm ≤ 2 mm
Spatial resolution Baseline Baseline
Contrast Baseline Baseline
Uniformity and noise Baseline Baseline
Planar kV Imaging Imaging and treatment coordinate coincidence (four cardinal angles)
≤ 2 mm ≤ 1 mm
Scaling ≤ 2 mm ≤ 1 mm
Spatial resolution Baseline Baseline
Contrast Baseline Baseline
Uniformity and noise Baseline Baseline
Cone-beam CT (kV and MV) Geometric distortion ≤ 2 mm ≤ 1 mm
Spatial resolution Baseline Baseline
Contrast Baseline Baseline
HU constancy Baseline Baseline
Uniformity and noise Baseline Baseline
Imaging Annual QA1 Procedure Non-SRS/SBRT SRS/SBRT
Planar MV imaging (EPID) Full range of travel SDD ±5 mm ±5 mm
Imaging dose Baseline Baseline
Planar kV imaging Beam quality/energy Baseline Baseline
Imaging dose Baseline Baseline
Cone-beam CT (kV and MV) Imaging dose Baseline Baseline
Radiographic Simulator Daily QA2 Procedure Tolerance
Localizing lasers 2 mm
Optical Distance Indicator (ODI) 2 mm
Radiographic Simulator Monthly QA2 Procedure Tolerance
Field size indicator 2 mm
Gantry/collimator angle indicators 1°
Cross-hair centering 2 mm diameter
Focal spot-axis indicator 2 mm
Fluoroscopic image quality Baseline
Emergency/collision avoidance Functional
Light/radiation field coincidence 2 mm or 1%
Film processor sensitometry Baseline
Radiographic Simulator Annual QA2 Procedure Tolerance
Mechanical Checks Collimator rotation isocenter 2 mm diameter
Gantry rotation isocenter 2 mm diameter
Couch rotation isocenter 2 mm diameter
Coincidence of collimator, gantry, couch axes, and isocenter
2 mm diameter
Tabletop sag 2 mm
Vertical travel of couch 2 mm
Radiographic Checks Exposure rate Baseline
Tabletop exposure with fluoroscopy Baseline
kVp and mAs calibration Baseline
High- and low-contrast resolution Baseline
CT Simulator Daily QA2,3 Procedure Test Objective Tolerance
Electromechanical Alignment of gantry lasers with the center of imaging plane
Verify proper identification of scan plane with gantry lasers
±2 mm
Image Performance CT number accuracy CT number for water 0±5 HU
Image Noise Manufacturer specifications
In plane spatial integrity x or y direction ±1 mm
CT Simulator Monthly QA2,3 Procedure Test Objective Tolerance
Electromechanical
Orientation of gantry lasers with the respect to imaging plane*
Verify gantry lasers are parallel & orthogonal with the imaging plane
over the full length of laser projection
±2 mm over length of laser projection
Spacing of lateral wall lasers with respect to lateral gantry lasers and scan plane*
Verify lateral wall lasers are accurately spaced from the scan
plane ±2 mm
Orientation of wall lasers with respect to the imaging plane*
Verify wall lasers are parallel & orthogonal with the imaging plane
over the full length of laser projection
±2 mm over length of laser projection
Orientation of ceiling lasers with respect to the imaging plane*
Verify ceiling laser is orthogonal with the imaging plane
±2 mm over length of laser projection
Orientation of CT-scanner tabletop with respect to imaging plane**
Verify CT-scanner tabletop is level & orthogonal with imaging plane
±2 mm over length and width of tabletop
Table vertical and longitudinal motion Verify table longitudinal motion according to digital indicators is
accurate & reproducible
±1 mm over the range of table motion
Image Performance CT number accuracy 4-5 different materials For water, 0±5 HU
In plane spatial integrity In both x & y directions ±1 mm
Field uniformity Most commonly used kVp within ±5 HU
* Monthly and after laser adjustments **Monthly or when daily laser QA tests reveal rotational problems
CT Simulator Semi-Annual QA2,3 Procedure Test Objective Tolerance
Electromechanical
Sensitivity profile width Verify the sensitivity profile width meets manufacturer specification
±1 mm of nominal value
CT Simulator Annual QA2,3 Procedure Test Objective Tolerance
Electromechanical
Table indexing and position Verify table indexing and position
accuracy under scanner control ±1 mm over scan range
Gantry tilt accuracy Verify accuracy of gantry tilt
indicators ±1° over gantry tilt range
Gantry tilt position accuracy Verify gantry accurately returns to
nominal position after tilting ±1° or ±1 mm from nominal
position
Scan localization Verify accuracy of scan localization
form pilot images ±1 mm over scan range
Radiation profile width Verify radiation profile width meets
manufacturer specification Manufacturer specifications
Image Performance CT number accuracy Electron density phantom For water, 0±5 HU
Field uniformity Other used kVp settings within ±5 HU
Electron density to CT number conversion Annually or after scanner calibration
Consistent with commissioning results & test
phantom manufacturer specifications
Spatial resolution Manufacturer specifications
Contrast resolution Manufacturer specifications
CT Simulator Other QA Parameters2,3
Procedure Test Objective Tolerance
Electromechanical
Generator tests (After replacement of major generator component)
Verify proper operation of x-ray generator
Manufacturer specifications or Report No. 39
recommendations
QA of Instruments4 Procedure Recommendations Frequency
General QA
Acceptance testing Ensure device is meeting manufacturer's
specifications Upon purchase
Commissioning Setup process for use and measurements;
proper training Prior to departmental
use
Inspection Inspection for wear and tear of equipment At time of use
Equipment QA intercomparisons Particularly for electronic devices Frequently
Comparison of QA results Global comparison of QA results for trends Periodically
Secondary check Measurement should be made using different
device for confirmation
When a large discrepancy is seen
during QA
Ionization Chambers & Electrometers Accredited Dosimetry Calibration Laboratory (ADCL) calibration
Act as the primary standard Calibrated every 2
years
Secondary ion chamber/electrometer Intercompared with the primary standard
Minimum of twice per year/ Before or after
any instrument is sent to ADCL for calibration
Beam Scanning Systems On-site acceptance testing, commissioning, & training
Ensure device is meeting manufacturer's specifications
Upon purchase
Functionality of scanning detectors, accuracy and reproducibility of moving in x,y,z directions, and functionality of software
Prior to use/ after software upgrade
Physics Instruments
Ruler (at least one) Calibrated traceable to the National Institute of
Standards and Technology (NIST)
Thermometer/Barometer Should have at least 2 of each device with one
set aside as reference, NIST traceable Upon purchase and at
least semi-annually
Barometer Intercomparisons to nearest weather station Whenever possible
Absolute & Relative Dose Measuring Equipment
Diode and MOSFET QA Monthly
TLD system QA Dependent on
frequency used
Film (radiographic of GaFChromic) QA Dependent on
frequency used
Survey Meters Calibration NRC, Agreement state or state requirement Yearly
Battery check Daily
Constancy check Use low activity radioactive check source to
verify proper operation Daily
MLC QA2 Procedure Tolerance
Patient Specific
Check of MLC-generated field vs. simulator film (or DRR) before each field treated
2 mm
Double check of MLC field by therapists for each fraction Expected field
On-line imaging verification for patient on each infraction Physician discretion
Port film approval before second fraction Physician discretion
Quarterly
Setting vs. light field vs. radiation field for two designated patterns 1 mm
Testing of network system Expected fields over network
Check of interlocks All must be operational
Annually Setting vs. light vs. radiation field for patterns over range of gantry and collimator angles
1 mm
Water scan of set patterns 50% radiation edge within 1 mm
Film scans to evaluate interleaf leakage and abutted leaf transmission Interleaf leakage <3%, abutted leakage
<25%
Review of procedures and in-service with therapists All operators must fully understand
operation and procedures
Dynamic/Universal/Virtual Wedges QA1
Procedure Dynamic
Tolerance Universal Tolerance
Virtual Tolerance
Daily
Morning check-out run for one angle Functional
Monthly
Wedge factor for all energies C.A. axis 45°or 60°
WF (within 2%) C.A. axis 45°or 60°
WF (within 2%) 5% from unity, otherwise 2%
Annual
Check of wedge angle for 60°, full field and spot check for intermediate angle, field size
Check of off-center ratios @ 80% field
width @ 10 cm to be within 2%
Acceptance Testing for TPS5 Topic Procedure
CT input Create an anatomical description based on a standard set of CT
scans provided by the vendor, in the format which will be employed by the user
Anatomical description Create a patient model based on the standard CT data discussed
above. Contour the external surface, internal anatomy, etc. Create 3D objects and display.
Beam description Verify that all beam technique functions work, using a standard
beam description provided by the vendor.
Photon beam dose calculations
Perform dose calculations for a standard photon beam dataset. Tests should include various open fields, different SSDs, blocked fields, MLC-shaped fields, inhomogeneity test cases, multi-beam
plans, asymmetric jaw fields, wedged fields, and others.
Electron beam dose calculations Perform dose calculations for a standard electron beam dataset. Include open fields, different SSDs, shaped fields, inhomogeneity
test cases, surface irregularity, test cases, and others.
Brachytherapy dose calculations
Perform dose calculations for single sources of each type, as well as several multi-source implant calculations, including standard
implant techniques such as a GYN insertion with tandem and ovoids, two-plane breast implant, etc.
Dose display, dose volume histograms
Display dose calculation results. Use a standard dose distribution provided by the vendor to verify that the DVH code words as
described. User-created dose distributions may also be used for additional tests.
Hardcopy output Print out all hardcopy documentation for a given series of plans and confirm that all textual and graphical information is output
correctly.
Treatment Planning System QA5 Procedure Recommendations
Daily QA
Error Log Review any error messages or hardware malfunctions and keep
log of changes
Change Log Keep log of hardware/software changes
Weekly Digitizer Review digitizer accuracy
Hardcopy output Review all hardcopy output, including scaling for plotter and
other graphics-type output
Computer files Verify integrity of all RTP system data files and executables using checksums or other simple software checks. Checking
software should be provided by vendor.
Review clinical planning Review clinical treatment planning activity. Discuss errors,
problems, complications, difficulties. Resolve problems.
Monthly
CT data input into RTP systems Review the CT data within the planning system for geometrical accuracy, CT number consistency and derived electron density
Problem review Review all RTP problems (for RTP system and clinical planning)
and prioritize problems to be resolved
Review of RTP systems Review current configuration and status of all RTP system
software, hardware, and data files
Annual
Dose calculations Annual checks. Review acceptability of agreement between
measured and calculated doses for each beam/source
Data and I/O devices Review functioning and accuracy of digitizer tablet, video/laser
digitizer, CT input, MR input, printers, plotters, and other imaging output devices
Critical software tools Review BEV/DRR generation and plot accuracy, CT geometry,
density conversions, DVH calculations, other critical tools, machine-specific conversions, data files, and other critical data
Variable
Beam parameterization Checks and/or recommissioning may be required due to
machine changes or problems
Software changes, including operating system Checks and/or recommissioning may be required due to
changes in the RTP software, any support/additional software such as image transfer software, or the operating systems
IMRT QA6 Topic Procedure
Radiation Safety
• Common to have 3-4x the number of MU for IMRT compare to conventional treatment • Primary barrier not a concern • Secondary barrier required to handle leakage radiation especially above 10 MV
Treatment Planning
• Commissioned for IMRT by verifying that the dose predicted by the planning system is accurate within acceptable limits • Geometric test patterns with predictable or known dose are performed
Machine Characteristics • MLC • Dose delivery
Patient-Specific Dose Verification • Must irradiate phantom to verify that the dose delivered is the dose planned
• Can be verified by:
o Point dose measurements for single field (film, ion chamber,
diodes)
o Point dose measurements for all fields (composite film, ion
chamber)
o Planar dose measurements for a single field (specified depth in
phantom, using array of diodes or film) o Planar dose measurements for multiple fields (film)
SRS QA6 Machine Type Guidelines
Linear Accelerator AAPM Report 54 'Stereotactic Radiosurgery'
Gamma Knife AAPM Report 54 "Stereotactic Radiosurgery" and AAPM Task Group 178 'Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance'
CyberKnife AAPM Report 135 'QA for robotic radiosurgery'
Brachytherapy- Sources QA7
Procedure Frequency Tolerance
Long half-life - Description
Physical/Chemical form Initial Purchase Documented
Source encapsulation Initial Purchase Documented
Radionuclide distribution and source uniformity
Initial Purchase Documented
Location of radionuclide Initial Purchase 1 mm
Long half-life - Calibration
Mean of batch Initial Purchase 3%
Deviation from mean Initial Purchase 5%, Documented
Calibration verification Every use
Visual check of source color code
or measurement in calibrator
Short half-life - Description
Physical/Chemical form Initial Purchase Documented
Source encapsulation Initial Purchase Documented
Short half-life - Calibration
Mean of batch Every use 3%
Deviation from mean Every use 5%
Radionuclide distribution and source uniformity
Every use Visual check,
autoradiograph, ionometric check
Brachytherapy - Intracavitary Source and Applicator QA7
Procedure End Point Frequency
Evaluate dimensions/serial number Source identity, physical length and diameter Initially
Superposition of auto-and transmission radiographs
Active source length and uniformity, capsule thickness, accuracy of source construction
Initially
Source leak test Capsule integrity At 6-month
intervals (NRC requirement)
Source calibration Source strength Initially, Annually
Dosimetric evaluation of applicator Magnitude and geometric characteristics of
shielding effect Initially
Orthogonal radiographs of applicators Correct source position, mechanical integrity,
internal shield positioning, coincidence of dummy and radioactive source
Initially, Annually
Measure applicator dimensions Correct diameter and length, correct diameter
of all colpostat caps and cylinder segments Initially, Annually
Source inventory Correct source number Quarterly
Source preparation area survey Safety of brachytherapy personnel As needed
Brachytherapy - Interstitial Source and Applicator QA7
Procedure End Point Frequency
Evaluate spacing and no. seeds/ribbons Ribbon geometry and seed quantity Initially
Source calibration Source strength Initially, Each use
Strength peer seed or strength per unit length
Source strength uniformity Initially
Applicator integrity Metal needles (sharpness and straightness)
Templates (o-ring integrity and hole locations) Initially, Annually
Evaluate dummy ribbon geometry Coincidence of dummy and radioactive
sources Initially, Annually
Source leak test Capsule integrity At 6-month
intervals (NRC requirement)
Source inventory Correct source number Quarterly
Source preparation area survey Safety of brachytherapy personnel As needed
Brachytherapy - Daily QA for Remote Afterloading7
Test Endpoint Test Methodology System Type
Dose delivery accuracy
Verify date, time and source strength in treatment unit and planning computer
All
Verify source strength and timer accuracy against a tertiary standard HDR/PDR
Overall system function
Run system through a complete cycle of simulated treatment:
All
• programming;
• source ejection;
• source retraction at end of timer countdown
Verify treatment status indicator lights and critical source control functions
Correct function of dedicated fluoroscopy/imaging system if present
HDR
Patient/public/staff safety Correct function:
• door interlock; HDR/PDR
• area radiation monitor; HDR/PDR
• audio/visual system communication; HDR/PDR
• portable survey meter; All
• audible/visual error and alarm condition indicators; All
Safety equipment available:
All
• emergency instructions;
• emergency equipment (forceps, emergency safe, surgical supplies);
• operator’s manual;
• survey meter
Measure hourly/weekly radiation levels after patient loaded and portable shields positioned
PDR/LDR
Verify positional accuracy within 1 mm Many possible tests:
All
• primary positional accuracy test for a single catheter;
• deviation of ion chamber response placed near a programmed dwell position;
• multiple-channel autoradiograph of every active dwell position used in the patient treatment and compare programmed position to expected;
• visually check that relative position of source tip in a ruled catheter reproduces from day-to-day
Autoradiograph patient-specific configuration of sources loaded into intermediate safe of device
All fixed and programmable
source-train units
Temporal accuracy Many possible tests:
HDR/PDR
• time duration of ‘‘source ejected’’ light;
• perform a spot check of radiation output for a timed interval using tertiary calibration standard jig;
• compare source arrival and departure times on printed treatment documentation with a clock or stop watch;
• for LDR, subtract treatment interruptions from overall treatment time and compare to programmed time LDR (optional)
Brachytherapy - Quarterly QA for Remote Afterloading7
General Endpoint Tests/Endpoints System Type
Personnel safety Head/machine survey with source retracted All
Patient safety
Important interlocks and emergency response systems function: obstructed applicator, missing applicator, door, unlocked indexer ring, displacement, power/ air pressure loss, backup battery system All
Emergency source handling tools, shielded storage container, and supplies for emergency applicator removal available and functioning All
Calibration of optical and pneumatic source position/status detection systems; any other preventive maintenance or inspections
As specified by vendor
All
Correct operation of all applicators, transfer tubes, and source localization dummies
Examine all dummies for kinks or bends that may shorten their axial displacement through applicator assembly. Check integrity of all transfer tube-applicator interfaces All
Positional accuracy: single stepping source
Verify that radioactive source position agrees with dummy marker within 0.5 mm previously tested against dwell position markers used in simulation.
All HDR/PDR single-stepping source devices
Confirm check cable operation
Obtain multiple channel autoradiograph with unique dwell sequence in each channel: verify that dwell position spacing, assignment of dwell sequence to programmed channel, and relative indexer length to dwell 1 are correct within 1 mm
Confirm accuracy of daily positional test protocol
Transfer tube length (if stability through time is not confirmed and positional accuracy is influenced by tube length)
Positional accuracy: multiple-source machines
Device positions source train in specified treatment location All
Source trains delivered to programmed channels within 1 mm of intended location All
Source trains correctly sorted and composed Programmable
source train
Source inventory correct All
Source trains stored in correct locations in user accessible storage location
Fixed source-train devices
Source calibration Measure source air kerma strength using a ‘secondary’ standard as described in Sec. III HDR/PDR
Redundant source calibration checks
Difference between measured and vendor-specified air kerma strength is within expected margin
HDR/PDR
Use tertiary source strength standard (e.g., daily/monthly output checking system) to confirm primary calibration within 5%. Different electrometer and detector to be used
Various techniques available (Williamson, 1991 and 1994) Spot check of absolute timer accuracy All LDR
Timer accuracy and linearity measurement HDR/PDR
Miscellaneous
Update source strength in treatment planning computer initialization file, treatment unit and quarterly inventory All
Have a second physicist independently review the quarterly report HDR/PDR
Brachytherapy - Annual QA for Remote Afterloading7
Test Endpoint Test Methodology System Type
Personnel and public safety Review workload and annualized unrestricted area/personnel exposures All
Perform facility survey if occupancy/building structure revised All
Dose delivery accuracy
Intercompare secondary standard used for quarterly calibration against another departmental substandard. Obtain new calibration from ADCL if calibration more than two years old
HDR/PDR
Verify air kerma strength calibration and other annual Table I checks LDR
Positional accuracy
Verify accuracy of any jigs or autoradiography cassettes used for daily/monthly positional accuracy verification All
Verify construction/spacing of all simulation markers (dummy sources) All
Verify position of simulation markers agrees with radioactive source for all applicator types. Verify simulation source localization procedure All
Apply Table I/II tests to all intracavitary/interstitial applicators All
If positional accuracy assumes fixed transfer tube length, verify length/uniformity if not checked quarterly All
Temporal accuracy Verify timer linearity and absolute accuracy All
Verify transit dose/source velocity All
Verify pulse sequencing PDR
Additional interlock/emergency response tests
Verify that unit detects simulated detached source capsule HDR/PDR
Verify emergency retraction buttons in room and manual source retraction crank function HDR/PDR
Verify that source retracts and emergency retraction motor activates when excessive friction/applicator obstruction encountered by source All
Miscellaneous
Check that treatment unit correctly decays source strengths and corrects dwell times for decay All
Review accuracy of all standard treatment configurations stored in treatment unit All
Review quality assurance manual and update if necessary. All
Review compliance with personnel training requirements. All
Brachytherapy - QA Computer Planning System7
Function Benchmark Data Frequency Verify geometric accuracy of I/O peripherals; digitizer, CT or ultrasound interface and plotter
Digitize/plot pattern of known geometry; for CT/US, image and reconstruct phantom implant Monthly
Verify input parameters for all precalculated single-source arrays
Published recommendations, source vendor's mechanical drawings, initially, annually Monthly
Verify dose, dwell time, and treatment time calculations at representative points for all source files
Published dose rate tables, manual calculations
Initially, annually, new software
version or source identity
Accuracy of single-source isodoses Point source output
Initially, new software version
Accuracy of multi-source isodose contouring Point source data for symmetric source arrays Initially, new
software version
Accuracy of plan rotation matrix
Constancy of point doses, source positions, and isodoses under repeated orthogonal rotations for symmetric source arrays
Initially, new software version
Consistency of printed plan documentation Assumed input parameters Every clinical use
Accuracy of coordinate reconstruction Radiograph phantom with known catheter geometry
Initially, new software version
Accuracy of electronic downloading of treatment parameters of afterloader
Comparison of treatment unit and planning system printed output
Initially, new software version, each treatment
Dose volume histogram/implant figures of merit
Use isotropic point source or segment of line source allowing analytic calculations of DVH
Initially, new software version
Constancy of test case DVH Annually
Optimization software
Run series of test cases based upon idealized implant geometries of various sizes; develop a sense of what optimization does to an implant compared to uniform loading before trying it on patients
Initially, spot check when software
changes by duplicating old
cases
Overall system check Run series of standardized plans to globally test all clinically used features
Initially, new software version,
annually
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