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General X-ray QA and QC
Guideline
THE ROYAL AUSTRALIAN AND NEW ZEALAND COLLEGE OF RADIOLOGISTS®
General X-ray QA and QC Guideline
Faculty of Clinical Radiology
Name of document and version:
General X-ray QA and QC Guideline, Version 1
Approved by:
Faculty of Clinical Radiology
Date of approval:
1 November 2013
ABN 37 000 029 863
Copyright for this publication rests with The Royal Australian and New Zealand College of
Radiologists ®
The Royal Australian and New Zealand College of Radiologists
Level 9, 51 Druitt Street
Sydney NSW 2000 Australia
Email: [email protected]
Website: www.ranzcr.edu.au
Telephone: +61 2 9268 9777
Facsimile: +61 2 9268 9799
Disclaimer: The information provided in this document is of a general nature only and is not intended as a
substitute for medical or legal advice. It is designed to support, not replace, the relationship that exists
between a patient and his/her doctor.
TABLE OF CONTENTS
1.
Introduction
3
2.
Daily / As Required Tests
5
3.
Weekly Tests
7
4.
Monthly Tests
9
5.
Quarterly Tests
13
6.
Six-Monthly Tests
28
7.
Review of QC Results by Designated Person
30
8.
Related policy documents
31
9.
Appendices
31
10. References
31
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 2 of 33
1. INTRODUCTION
1.1
Preamble
Quality Assurance is a planned and systematic approach to monitoring and assessing the
care provided, or the service being delivered, that identifies opportunities for improvement
and maintains a mechanism through which action is taken to make and maintain these
improvements (Australian Council of Healthcare Standards).
The scope of activities in the quality management process for general radiology imaging
systems includes, but is not limited to:
i.
Radiation protection and radiation monitoring (optimisation of radiation dose and
image quality, structured dose reports, establishment of diagnostic reference
levels);
ii.
Equipment testing (routine Quality Control);
iii.
Other recommended QA systems for general imaging (CR and DR systems), film
printing, screening/fluoroscopy, mobile imaging, and theatre imaging;
iv.
Clinical image review and repeat / reject analysis
This document has been produced as a resource document for best practice in these areas
of quality management in Medical Imaging departments and assumes that all additional
state / legislative requirements such as equipment compliance testing, licencing,
registration, record keeping and regular service maintenance tests are conducted as part
of routine site accreditation requirements.
1.2
1.3
Purpose and Scope
(a)
This guideline is intended to assist The Royal Australian and New Zealand College
of Radiologists® (ABN 37 000 029 863) (the College), radiologists, radiographers,
equipment assessors in addressing quality control requirements relating to
radiography equipment. This document sets out standardised procedures and
instructions to complete quality control processes.
(b)
This document will be reviewed at the end of 2015. Please refer to individual
manufacturers’ guidelines for any additional Quality Assurance requirements that
may be applicable for specific systems.
Overarching Management of QA and QC
It is recommended that at least one staff member at each facility is identified and
responsible for ensuring quality checks are undertaken at specified times. The designated
person(s) may include one or more of the following staff members: Chief Radiographer /
Assistant Chief Radiographer / Quality Manager / QA Radiographer / Section Senior
Radiographer / RSO. The designated quality manager should also review non-compliance
issues and provide strategies for corrective and preventative action in a timely manner and
formulate quality improvement strategies within the department.
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 3 of 33
The designated quality manager is also responsible for the organisation, dissemination and
document control of all incoming quality guidelines, policies and directives from accrediting
/ regulatory bodies (e.g. RANZCR & ISO/IEC / Radiation Protection Authority), Local
Health Service and State Departments of Health.
1.4
Reviewing QC Results and Taking Action
It is essential to review QC results immediately and take action if they are out of tolerance.
In some cases, it may be necessary to contact the service engineer. The urgency of
remedial action by the service engineer should be determined by personal judgment. For
example, a minor failure in x-ray to light-beam alignment could be fixed at the next service
visit but anything that may affect patient dose or image quality should be addressed
immediately. Prior to contacting the service engineer, you may wish to carry out the
following steps:
1.5
i.
Repeat the test. If you are not confident in carrying out QC tests, consult an
experienced colleague ;
ii.
Check that you have used correct and consistent settings e.g. kV, mAs, test object,
focus to detector distance;
iii.
If artefacts are present, try to identify their location e.g. on the monitor, the
detector, the test object. Clean equipment and repeat the test;
iv.
Contact your medical physicist / equipment assessor for advice (if available)
Acknowledgements
The Royal Australian and New Zealand College of Radiologists gratefully acknowledges
the extensive work undertaken by the General X-Ray working group consisting of Dr
Patrick Brennan, Ms Ingrid Egan, Dr Nick Pang, Mr John Robinson, Dr Andrew Scott and
representatives of the ACPSEM Dr Lee Collins, Dr Jenny Diffey and Dr Ian Smith, in
development of this guideline.
1.6
Definitions
In this Guideline:
College means The Royal Australian and New Zealand College of Radiologists.
Member means a member of the College.
1.7
College Mission
The College’s Mission is:
As a fellowship based organisation, The Royal Australian and New Zealand College of
Radiologists sets, promotes and continuously improves the standards of training and
practice in radiology and radiation oncology, for the betterment of the people of Australia
and New Zealand.
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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2. DAILY / AS REQUIRED TESTS
2.1
Detector Calibration / Flat Field / Dark Noise Test (DR Only)
Frequency: As recommended by manufacturer (see below).
Tests such as Detector Calibration are not specifically included in the RANZCR guidelines,
due to vendor variability. For example, Carestream require a daily detector calibration,
known as the ‘Daily Dark’, whilst other vendors require an annual detector calibration which
is normally performed by the service engineer.
For this reason, no specific protocol or frequency is defined by RANZCR. Instead, the
advice of the Working Group is simply to follow the advice of the vendor.
These tests are generally ‘pass / fail’ and no output is recorded. An example form for
recording that a daily detector calibration has been completed is included as Record Sheet
2.1.a.
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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2.1.a Record Sheet - Daily Detector Calibration
X-ray equipment ID: ________________
Month:
DR manufacturer: ________________
Test (e.g. Daily Dark): ___________________
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Pass () / Fail ()
Initials
Month:
Pass () / Fail ()
Initials
Month:
Pass () / Fail ()
Initials
Month:
Pass () / Fail ()
Initials
3. WEEKLY TESTS
3.1
Image Plate Erasure (CR Only)
Frequency: Weekly
CR image plates are sensitive to scattered and naturally occurring radiation sources and if
left unused for long periods of time will store energy absorbed from these sources. It is
recommended that all CR image plates be subjected to a “primary” erasure procedure on a
weekly basis, ideally on a Monday morning.
Note that this frequency is based on the assumption that unused cassettes are stored
under conditions whereby they are unlikely to receive any significant unintended exposure.
Should unexposed cassette storage be less than optimal, an increased frequency of plate
erasure will be required.
3.1.1 Procedure
 Perform a primary erasure on all CR cassettes
 Complete Record Sheet 3.1.a
3.1.2 Record
 Date test was performed
 Person performing test
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 7 of 33
3.1.a Record Sheet – Image Plate Erasure (CR only)
Frequency: Weekly
Site / Department: ____________________________
Date
Initials
Date
Initials
Date
Initials
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 8 of 33
4. MONTHLY TESTS
4.1
Monitor QC
Frequency: Monthly Test
The monitor in the x-ray room, attached to the operating console, is referred to as the
secondary or acquisition monitor. The high resolution monitors used for reporting the x-ray
examination images are known as the primary or reporting / diagnostic review monitors. It
is ONLY necessary to carry out this test on the primary (reporting) monitors.
4.1.1 Procedure
 Display the appropriate version of the TG18-QC test pattern (see Appendix 1)
 If window width (WW) and window level (WL) are displayed, these should be set to
4096 and 2048 respectively. Please note that these will not always be displayed, or be
adjustable. If the pattern has been installed correctly, these will be the default settings
 Ensure viewing conditions are acceptable
 Examine image paying particular attention to the following:
o Visibility and distortion of items used for the evaluation of the quality of the image
o Disturbing artefacts
 Visually check for fingerprints and dust and clean gently using a lint-free cloth, or as per
manufacturer’s recommendations
 If monitors are installed as a pair, visually check that the luminance of the left and right
monitors are matched i.e. white, dark and grey squares should appear to have the same
greyscale (please be aware that this test is subjective!)
 Complete monthly checklist and Record Sheet 4.1.a (you will need one Record Sheet
for each monitor / pair of monitors)
4.1.2 Record




Date test was performed
Person performing test
Monitor identification
Test results
4.1.3 Limits

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Borders are visible
Lines are straight
Squares appear square
No smearing at black-white transitions
Squares of different shades from black to white are distinct
The finest horizontal and vertical line pairs are visible in the high contrast pattern in all
four corners and in the centre
The 5% and 95% pixel value squares are clearly visible within the 0% and 100%
backgrounds
The pattern is centred in the active area
No disturbing artefacts are visible
At least 11 letters (i.e. QUALITY CONT) are visible in the phrase “QUALITY CONTROL”
for the dark, mid-grey and light renditions. Note that you should record how many letters
can be seen
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 9 of 33
4.1.a Record Sheet – Monitor QC
Frequency: Monthly Test
Monitor ID (e.g. vendor, model, location): _______________________________________
Date:
Initials:
Left / right (if applicable)
Left / Right / NA
Left / Right / NA
Left / Right / NA
Left / Right / NA
Pass () / Fail ()
General Image Quality
No smearing
No artefacts
Ramps continuous
General distortion
Lines straight
Boxes square
Luminance
Greyscale patches
distinct
5% square visible in
0% background
95% square visible in
100% background
Finest high contrast resolution elements visible (in all 4 corners and at centre)
Horizontal line pairs
Vertical line pairs
Number of letters visible (at least 11 or “QUALITY CONT”)
Dark
Mid-grey
Light
Visual check for fingerprints / dust and cleaning (if required)
Completed
Monitor matching if applicable (subjectively by eye)
Dark areas matched
White areas matched
Comments
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 10 of 33
4.2
Printer QC (if applicable)
Frequency: Monthly Test, or prior to printing if used less frequently
Please note: Although many practices will not be printing films for primary reporting, it is
still important to make sure that printed images are of a relatively high standard if being
sent as the medical record.
It is acknowledged that sites will no longer own a densitometer and for this reason, a visual
check only is considered sufficient. It is expected that the Service Engineer will confirm that
the optical density range is acceptable during their routine service visit.
Note that a Printer Calibration is also required at installation, but this should be done in
conjunction with the Service Engineer. Given that there may be a large number of x-ray
equipment vendors at a single site, it is recommended that clinical images are sent to the
printer from PACS, rather than from the Acquisition Workstation.
4.2.1 Procedure
 Print the TG18-QC test pattern (see Appendix 1) directly from the printer.
 Check visibility and distortion of several items used for evaluating the quality of the
image
 Check for disturbing artefacts
 Clean the rollers (as required; based on frequency of use)
 Complete monthly check list and Record Sheet 4.2.a (you will need one Record Sheet
for each printer)
4.2.2 Record




Date test was performed
Person performing test
Printer identification
Test results
4.2.3 Limits
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Borders are visible
Lines are straight
Squares appear square
Squares of different shades from black to white are distinct
The finest horizontal and vertical line pairs are visible in the high contrast pattern in all
four corners and in the centre
The 5% and 95% grey squares are clearly visible within the 0% and 100% backgrounds
At least 11 letters (i.e. QUALITY CONT) are visible in the phrase “QUALITY CONTROL”
for each of the dark, mid-grey and light renditions. Note that you should record how
many letters can be seen
No disturbing artefacts are visible
Rollers clean
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 11 of 33
4.2.a Record Sheet – Printer QC
Frequency: Monthly Test, or prior to printing if used less frequently
Printer ID (e.g. vendor, model, location): ____________________________________
Date:
Initials:
Pass () / Fail ()
General Image Quality
No smearing
No artefacts
Ramps continuous
General distortion
Lines straight
Boxes square
Luminance
Greyscale patches distinct
5% square visible in 0% background
95% square visible in 100% background
Finest high contrast resolution elements visible (in all 4 corners and at centre)
Horizontal line pairs
Vertical line pairs
Number of letters visible (at least 11 or “QUALITY CONT”)
Dark
Mid-grey
Light
Printer rollers
Cleaned (if required)
Comments
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 12 of 33
5. QUARTERLY TESTS
5.1
Mechanical Inspection
Frequency: Quarterly
The practice staff must perform an overall mechanical inspection of the digital x-ray system
and associated components. The inspection should be carried out quarterly to ensure that
there are no hazardous, inoperative, out of alignment or improperly operating items on the
system.
The Service Engineer may perform additional checks during their service visit, for example
CR Plate Sensitivity Matching. It is good practice to keep their service report alongside the
site QC records.
5.1.1 Procedure
Visual inspection of the system to ensure safe and optimum operation, using the checklist
provided on Record Sheet 5.1.a.
5.1.2 Record
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
Date inspection performed
Inspection results
X-ray equipment identification
Person performing test
5.1.3 Limits
 Mechanical and safety functions operating correctly
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 13 of 33
5.1.a Record Sheet – Mechanical Inspection
Frequency: Quarterly
X-ray Equipment ID: ____________________________________________________
Date:
Initials:
Item
Description
1
Check that all cables are free from breaks, kinks or knots. Cables should not be
under other heavy equipment
2
Verify that the interlocks and brakes are working correctly
3
Ensure that the table, tube and bucky move smoothly
4
Ensure that control panel switches, indicator lights and meters are functioning
5
Ensure that the field light is functioning, has adequate intensity and collimator is
free from dust
6
Ensure that the current technique charts are displayed near the control panel
7
Ensure that there are no oil leaks around the x-ray tube and generator, and that
these are free from dust
8
Check that CR plates are clean and free from artefacts (CR only)
Pass () Fail ()
On the reporting workstation, display a recent clinical image and verify that the
time and date as well as the facility identification are correct in the image
annotation
Check that the x-ray tube and generator model and serial numbers are clearly
marked and readable (if labels are inaccessible, serial numbers must be
displayed elsewhere e.g. in a file or label drawer)
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Visually inspect gonad shields and personal protective devices (e.g. lead aprons,
a
thyroid shields) for shielding integrity
12
Confirm that the operator’s view of the patient from the control window is not
obstructed by notices / charts
13
b
Ensure that the radiation warning sign on the door is intact and that the room
warning lights are working
14
b
Ensure that cassette localization / auto-collimation and locks are working
15
b
Check that centring and Source to Image Distance (SID) detents work correctly.
Verify the accuracy of the distance displayed on the collimator
a
Although a visual inspection will suffice on a quarterly basis, please be aware that some State
legislation (e.g. NSW EPA) requires that lead aprons are fluoroscopically screened on an
annual basis
b
Not applicable to mobile units
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 14 of 33
5.2
Alignment: X-ray to light field (CR and wireless DR detectors) / X-ray to
detector (integrated DR detectors)
Frequency: Quarterly
To ensure accurate collimation and full coverage of image receptor without unnecessary
exposure of patient. This test should be performed on all x-ray units.
5.2.1 Procedure
CR and wireless DR detectors

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Ensure x-ray tube and table are level.
Place CR cassette / wireless DR detector on table top.
Set a source to detector distance of 100cm
Dim the room lights so that you can clearly see the edges of the light field
Collimate to an area greater than 10 x 10cm – the exact area is not important as long as
it is within the CR cassette / wireless DR detector.
 Use coins to mark the edges of the light field. It is good practice to place a coin within
and outside the light field (see Figure 1). Use an additional coin to mark the anode side.
Edges of light
field
Coin to mark
anode side
Figure 1: Position of coins for x-ray to light-beam alignment test
 Make an exposure using 60kV and 5mAs
 Open up the collimators fully and make an exposure using 60kV and 1mAs.
 Readout the CR / DR image. Measure the difference between the x-ray field and the
edge of the coin (light field)
 Repeat for broad and fine focus (if available).
 Note that if the x-ray field is greater than the light field, this is a +ve difference
 Complete Record Sheet 5.2.a
Integrated DR detectors
These are units where the digital detector is built in to the bucky. Markings on the top of the
bucky show the position of the detector.

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Ensure x-ray tube and table are level
Set a source to detector distance of 100cm
Set auto-collimation
Dim the room lights so that you can clearly see the edges of the light field. Visually
check that the light field coincides with the markings on the bucky
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 15 of 33
 Switch the room lights on. Align coins with the edges of the markings on the bucky. Use
an additional coin to mark the anode side.
 Make an exposure using 60kV and 5mAs
 Measure the difference between the edge of the image and the edge of the coin (lightfield)
 Repeat for broad and fine focus (if available)
 Note that if the imaged field is greater than the edge of the markings, this is a +ve
difference
 The x-rays should extend to all edges of the detector (i.e. there should be no white
bands around the edge of the image)
 Complete Record Sheet 5.2.b
5.2.2 Record
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Date test was performed
Deviation of x-ray from light field / detector
X-ray equipment identification
Person performing test
5.2.3 Limits
 X-ray to light-field must be within ±1% of SID
 X-ray to detector must agree to within 2% of SID. X-ray field should extend to all edges
of the detector
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 16 of 33
5.2.a Record Sheet – Alignment: X-ray to light field (CR and wireless DR detectors)
Frequency: Quarterly
X-ray Equipment ID: _____________________
LIMITS
X-ray to light field must be within ± 1% of SID (i.e. ± 1 cm for SID of 100 cm)
Date
Initials
Broad Focus
Deviation between X-ray and light field (mm)
(positive indicates x-rays extend beyond light field)
Anode Edge
Cathode Edge
Top Edge
Bottom Edge
Fine Focus
Deviation between X-ray and light field (mm)
(positive indicates x-rays extend beyond light field)
Anode Edge
Cathode Edge
Top Edge
Bottom Edge
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 17 of 33
5.2.b Record Sheet – Alignment: X-ray to detector (integrated DR detectors)
Frequency: Quarterly
X-ray Equipment ID: _____________________
LIMITS
X-ray to detector must agree to within 2% of SID
X-ray field should extend to all edges of the detector
Light field should coincide with markings on bucky
Date
Initials
Broad Focus
Deviation between x-ray imaged field and detector markings (mm)
(positive indicates that the imaged field is greater than the detector markings on the bucky)
Anode Edge
Cathode Edge
Top Edge
Bottom Edge
Confirm that the light field coincides with the markings on the bucky
Pass () Fail
()
Comments
Fine Focus
Deviation between x-ray imaged field and detector markings (mm)
(positive indicates that the imaged field is greater than the detector markings on the bucky)
Anode Edge
Cathode Edge
Top Edge
Bottom Edge
Confirm that the light field coincides with the markings on the bucky
Pass () Fail
()
Comments
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 18 of 33
5.3
Consistency of Exposure Index
Frequency: Quarterly
To ensure that exposure index remains approximately constant under given exposure
conditions.
Note that this test requires you to set a baseline. This is done by following the procedure
below and performing the test on 3 occasions (separated by e.g. an hour or a day). Doing it
3 times in a row is not recommended. If the results are consistent, set the average value as
your baseline. Make a note of the date you set the baseline. All future results are compared
to this value.
If results are not consistent, repeat the test checking that you have followed the correct
procedure using identical exposure conditions.
There are occasions where it may be necessary to set a new baseline value, for example,
following software upgrades or tube changes. Follow the steps described above and note
the date the new baseline was set and the reason for the change. You should not set a
new baseline simply because the test fails, unless an investigation of the reason for the
failure indicates that this is justified.
5.3.1 Procedure
CR
A designated CR test cassette (freshly erased) and CR reader must be assigned for this
test; this ensures consistency of measurement conditions. It is preferable to assign a
cassette which is in clinical use as this will enable any deterioration due to general wear
and tear to be detected, which may indicate that image plates are due for replacement. The
test should be performed on all x-ray units.
Note that in departments with multiple CR readers, it is considered good practice to repeat
the test for all CR readers using one designated x-ray unit to make the exposures (there is
no need to test all combinations of x-ray units and CR readers).
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Place the CR test cassette on the table
Set focus to table distance of 110cm and centre x-ray beam on CR cassette
Ensure collimator position covers the full area of the CR plate
Attach 1mm copper sheet to tube collimator, ensuring beam fully intercepted
Make a manual exposure using 70kV, 4mAs
Process the image plate using a consistent image processing algorithm (e.g. L-spine)
Record the Exposure Index (note that this will be manufacturer-specific e.g. Fuji = S
number, Carestream = EI, Agfa = SAL or LgM)
 Use Record Sheet 5.3a
DR
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If using a wireless DR detector, place this on the table
Set focus to detector distance of 110cm and centre x-ray beam on detector
Ensure collimator position covers the full area of the detector
Attach 1mm copper sheet to tube collimator, ensuring beam fully intercepted
Use a consistent image processing algorithm (e.g. L-spine)
Make a manual exposure using 70kV, 4mAs
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 19 of 33
 Record the Exposure Index (note that this will be manufacturer-specific e.g. Carestream
& Philips = EI, Canon = EXI, Shimadzu = S number)
 Use Record Sheet 5.3a
5.3.2 Record
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Date test was performed
Processing algorithm
Exposure Index
X-ray equipment identification
Person performing test
5.3.3 Limits
 Exposure Index should be within ± 10% of the baseline value
 If the change in Exposure Index over consecutive periods follows a trend (e.g. a
continual increase or decrease in value), discuss the results with the Service Engineer
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 20 of 33
5.3.a Record Sheet – Consistency of Exposure Index
Frequency: Quarterly
CR Systems Only
CR Test Cassette ID: _____________________
CR Reader ID: __________________________
X-ray Equipment ID: _____________________
LIMITS
Variation of the EI from the baseline value < ± 10%
BASELINE DATA: Specify Exposure Indicator e.g. S number, EI ____________________
Date ____________
Baseline
Lower Limit
Upper Limit
EI
Date
Initials
Processing Algorithm
EI
EI within limits (P / F)
Comments
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 21 of 33
5.4
Image Uniformity and Artefact Evaluation
Frequency: Quarterly
To ensure that image is uniform and artefact-free. Additionally for DR, to ensure that flatfield correction is working.
Note that as part of the process of “image critique”, every clinical image acquired should be
subject to a quick artefact check before being sent to PACS or printed
5.4.1 Procedure
Use the image acquired for 5.3 Consistency of Exposure Index. Visually inspect the image
for non-uniformity and artefacts, accepting that CR images will suffer from the anode-heel
effect (i.e. a decrease in greyscale intensity as you move from the cathode to the anode
side of the image). Use Record Sheet 5.4.a.
5.4.2 Record




Date test was performed
Comments on uniformity and artefacts
X-ray equipment identification
Person performing test
5.4.3 Limits
 Uniform image
 No evidence of artefacts
5.4.4 Action
If artefacts are seen it is important to determine whether they are due to the monitor, the
detector, x-ray beam non-uniformity or the copper. Take the following steps:
 To eliminate the possibility of display artefacts, rotate or pan the image. If the artefact
moves with the image it is due to the imaging system; if it stays in the same place, it is
due to the display system (monitor).
 To eliminate the possibility of artefacts (dust, scratches or thickness non-uniformity) on
the copper, rotate the copper and repeat the test. If the artefact stays in the same
place, it is most likely to be due to the detector; if it moves, it may be attributable to nonuniformity on the copper.
 Clean the equipment (if possible and following vendor guidelines) and repeat the test.
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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5.4.a Record Sheet – Image Uniformity and Artefact Evaluation
Frequency: Quarterly
X-ray Equipment ID: _____________________
LIMITS
Image appears uniform
No artefacts present
Date
Initials
Image appears
uniform? (Y/N)
Comments (heel
effect etc?)
Artefacts present?
(Y/N)
Describe
Action taken (if
applicable)
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© The Royal Australian and New Zealand College of Radiologists®
November 2013
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5.5
AEC Consistency
It is important to ensure that the AEC operation remains stable over time. This should be
checked using table and vertical buckies and by choosing examinations which encompass
a range of AEC chambers.
Note that this test requires you to set baseline values for mAs and EI for each examination.
This is done by following the procedure below and performing the test on 3 occasions
(separated by e.g. an hour or a day). Doing it 3 times in a row is not recommended. If the
results are consistent, set the average value as your baseline. Make a note of the date you
set the baseline. All future results are compared to this value.
If results are not consistent, repeat the test checking that you have followed the correct
procedure using identical exposure conditions.
There are occasions where it may be necessary to set a new baseline value, for example,
following software upgrades or tube changes. Follow the steps described above and note
the date the new baseline was set and the reason for the change. You should not set a
new baseline simply because the test fails, unless an investigation of the reason for the
failure indicates that this is justified.
5.5.1 Procedure
 Select up to 3 frequently performed clinical examinations which are carried out under
AEC. Try to include examinations which cover table and vertical buckies (if applicable)
and a range of AEC chambers (e.g. Table bucky: L-Spine & Abdomen / Pelvis; Vertical
bucky: Chest). Record these in the table on Record Sheet 4.5a
 Place designated CR test cassette / wireless digital detector in bucky (if applicable)
 For the table bucky, set the source to detector distance that would be used clinically
(e.g. 110cm) and centre the x-ray beam to the centre of the bucky and the detector
 Ensure collimator position covers the full area of the AEC chambers
 Attach 1mm copper sheet to tube collimator, ensuring beam fully intercepted
 Select your examination (see table) and choose the clinically relevant kVp (e.g. 70kVp)
 Make an exposure under AEC and record indicated post-exposure mAs value
 Record the Exposure Index (note that this will be manufacturer-specific e.g. Fuji = S
number, Carestream = EI, Agfa = SAL or LgM)
 Repeat for the second selected examination (see table)
 Repeat for the vertical bucky (if applicable), setting the SID and kVp that would be used
clinically
 Use Record Sheet 5.5.a
5.5.2 Record







Complete table of up to 3 frequently performed examinations
Date test was performed
Person performing test
X-ray system identification
Current density setting
post exposure mAs
Exposure Index
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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5.5.3 Limits
 Post-exposure mAs within ± 20% of baseline values
No limits are set for Exposure Index, due to vendor variability, but if the change in
Exposure Index over consecutive periods follows a trend (e.g. a continual increase or
decrease in value), discuss the results with the Service Engineer
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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5.5.a Record Sheet – AEC Consistency
Frequency: Quarterly
X-ray Equipment ID: ____________________
Choose up to 3 frequently performed clinical examinations which are carried out under
AEC and record the factors below.
Examination
Bucky used
1
Table
2
Table
3
Vertical
kVp
Chamber(s)
Grid
(Y/N)
SID
(cm)
LIMITS
mAs ±20%
No limits are set for Exposure Index, due to vendor variability, but if the change in Exposure
Index over consecutive periods follows a trend (e.g. a continual increase or decrease in
value), discuss the results with the Service Engineer
BASELINE DATA
Date:
Baseline
Lower Limit
Upper Limit
mAs for Exam 1
mAs for Exam 2
mAs for Exam 3
EI for Exam 1
EI for Exam 2
Not required
EI for Exam 3
General X-ray QA and QC Guideline V1
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November 2013
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Date : ____________________
Examination
Density
setting
kV
Initials: _____________________________
Post
Exposure
mAs
mAs
within
acceptable
range
(/)
Exposure
Indicator
EI within
acceptable
range (/)
1
2
3
Date : ____________________
Examination
Density
setting
kV
Initials: _____________________________
Post
Exposure
mAs
mAs
within
acceptable
range
(/)
Exposure
Indicator
EI within
acceptable
range (/)
1
2
3
Date : ____________________
Examination
Density
setting
kV
Initials: _____________________________
Post
Exposure
mAs
mAs
within
acceptable
range
(/)
Exposure
Indicator
EI within
acceptable
range (/)
1
2
3
Date : ____________________
Examination
Density
setting
kV
Initials: _____________________________
Post
Exposure
mAs
mAs
within
acceptable
range
(/)
Exposure
Indicator
EI within
acceptable
range (/)
1
2
3
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 27 of 33
6. SIX-MONTHLY TESTS
6.1
Image Quality
Frequency: Six Monthly
To ensure adequate image quality from each x-ray unit.
Procedure
 Select 5 patients (mix of male and female) who have had a chest PA / AP x-ray for each
x-ray unit
 Perform an assessment of image quality using the checklist on Record Sheet 6.1.a
Record




Date of assessment
X-ray equipment ID
Radiologist performing test
Complete checklist
Limits
 Images must be deemed clinically acceptable. If not, the reasons must be investigated.
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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6.1.a Record Sheet – Image Quality
Frequency: Six Monthly
Date: _________________________
X-ray Equipment ID: ____________________
Name of Radiologist _____________________________________________________
Film 1
Chest AP / PA
Film 2
Film 3
Film 4
Film 5
Exposure Indicator
Image Assessment Criteria for Chest PA
1. Performed at deep inspiration (as
assessed by the position of ribs above the
diaphragm either 6 anteriorly or 10
posteriorly)
2.
The spinous processes of the dorsal
vertebrae are equidistant from the inner
borders of the clavicles (no thorax rotation)
3. Medial border of the scapulae to be
projected outside the lung fields
4. Reproduction from the 7th cervical vertebra
to the bottom of both costophrenic sinuses
(reproduction of the whole thoracic cavity)
5. Visually sharp reproduction of the
peripheral vessels (performed with
suspended respiration)
6. Visually sharp reproduction of the trachea,
major bronchi, and borders of the cardiac
silhouette
7. Visually sharp reproduction of both
hemidiaphragms
8. Visualization of the lung vessels and
mediastinal outline through the cardiac
silhouette
9. The lower dorsal spine is no more than
faintly appreciable with visualization of the
intervertebral spaces
10. Quality overall acceptable for clinical
purpose
Poor
Satisfactory
Good
Features invisible, detail invisible or not clear
Features just visible, detail just visible but not clearly defined
Features detected and fully reproduced, detail visible and clearly defined
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 29 of 33
7. REVIEW OF QC RESULTS BY DESIGNATED PERSON
The Designated Person may wish to use the form below to record the results of their review.
Site: _____________________________________________ X-ray Equipment ID: _____________________________________
Year
Jan
Feb
Mar
Apr
May
Jun
Jul
Image Plate Erasure (Weekly)
Monitor QC (Monthly)
Printer QC (Monthly)
Mechanical inspection (Quarterly)
X-ray Alignment (Quarterly)
Consistency of Exposure Index (Quarterly)
Image Uniformity and Artefact Evaluation (Quarterly)
AEC Consistency (Quarterly)
Image Quality (Quarterly)
Comments
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 30 of 33
Aug
Sep
Oct
Nov
Dec
8. RELATED POLICY DOCUMENTS
 Guideline for Quality Control Testing for Digital (CR and DR) Mammography V3.
9. APPENDICES
A. Monitor and Printer Quality Control: TG18 Test Pattern
10. REFERENCES
CRCPD (Conference of Radiation Control Program Directors) QC Recommendation Vol 3
EPA Radiation Guidelines
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
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Appendix A
Monitor and Printer Quality Control: TG18-QC Test Pattern
Display devices (monitors and printers) form part of the imaging chain and it is imperative that QC
is carried out to ensure that:
1) they meet the required standards at baseline, and
2) performance does not deteriorate over time.
In order to do this, the American Association of Physicists in Medicine (AAPM) has developed a
1
series of test patterns known as the Task Group 18 (TG18) series . These are not physical test
objects, but exist as files which can be loaded on to systems and displayed on the monitor or
printed. It is important to know how to access them. Sometimes they are locked as a patient in
PACS, but more commonly, they may be accessed through vendor-specific software such as
Barco QA Web or Eizo RadiCS.
The TG18-QC test pattern is shown overleaf. This should be displayed at full resolution (one
display pixel for each pixel in the digital image). A visual inspection of the image should be
carried out including tests such as:







Are the squares from black (100%) to white (0%) distinct?
Can you see the 95% square inside the 100% square?
Can you see the 5% square inside the 0% square?
Can you see the contrast patches in the corners of each grayscale square?
Can you resolve the high contrast and low contrast line pair groups in all four corners and
the centre?
Can you see at least 11 letters in the phrase QUALITY CONTROL?
Are the grayscale ramps on the left and right of the image continuous (i.e. does the black
blend smoothly into the white)?
Further details are given in the test protocols (4.1 and 4.2).
General X-ray QA and QC Guideline V1
© The Royal Australian and New Zealand College of Radiologists®
November 2013
Page 32 of 33
Appendix A
Figure 2: TG18-QC test pattern showing resolution patterns, ramps, 5% and 95% squares and
corner patches
1. Assessment of Display Performance for Medical Imaging Systems. American Association
of Physicists in Medicine. www.aapm.org/pubs/reports/OR_03.pdf
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© The Royal Australian and New Zealand College of Radiologists®
November 2013
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THE ROYAL AUSTRALIAN AND NEW ZEALAND COLLEGE OF RADIOLOGISTS®