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(2) Apply the compression force typically used clinically (e.g. 80 N).(3) Acquire an image of the test object using standard clinical settings. The DICOM ‘for presentation’ version ofthe image should be used for this test (see Section 2.3.7.2).(4) View the ‘for presentation’ image on the acquisition display workstation. Use the window width and windowlevel recommended by the medical physicist. These settings result in the background of the phantom beingdisplayed as a mid-grey. The same window width and window level settings (±10) should be used each timean image is evaluated. An appropriate choice of window width is critical for catching artefacts yet not‘failing’ clinically acceptable images. Window width choice should be based on what is appropriate or typicalfor breast images or for a phantom with breast-like features.(5) With the same window width and window level as used above, evaluate the entire image for overallappearance and for artefacts. Examine the entire image for both broad area artefacts such as non-uniformities,blotches and streaks, and for detailed artefacts such as black or white pixels, clusters of pixels, lines andspecks. Broad area artefacts are typically best seen while observing the phantom image as a whole, notpiecewise. Detailed artefacts are typically best seen while observing the phantom image at full spatialresolution, where one pixel on the display corresponds to one pixel in the image, or even in magnified form(with a magnification greater than 1.0). Record the absence or presence of artefacts on the daily flat fieldphantom image on the data collection sheet (Chart 7 in Annex I).Note: An artefact is considered significant if it may mimic or obscure anatomic features.7.1.3.4. Interpretation of results and conclusions(1) There should be no blotches or regions of altered texture appearance.(2) There should be no observable lines or structural artefacts.(3) There should be no ‘bright’ or ‘dark’ pixels evident.7.1.3.5. Recommendations and corrective actionsIf any artefacts are visible that might mimic or obscure anatomic information, or if any patterns are seen, arecalibration or flat fielding of the digital detector may be needed for DX systems. The compression plate and allaccessible surfaces that are in the imaging field should be cleaned to remove any debris or extraneous material. (ForCR systems, see also Section 7.1.4.) After this has been done, repeat the test. If artefacts persist, contact theauthorized service representative.7.1.3.6. Time frame for corrective actionImmediately: If this test fails, do not image patients until corrective action has been taken.44
7.1.4. Visual inspection for artefacts (CR systems only)7.1.4.1. ScopeDust on CR plates or debris on the breast support plate or the compression plate can create artefacts thatmimic microcalcifications (Fig. 18(a)). Scratches or other defects on the plates can interfere with imageinterpretation, and dust on the optics of the plate reader can cause disturbing linear artefacts on images (Fig. 18(b)).— Objective: To ensure that clinical images are free of artefacts that might interfere with image interpretation.— Frequency: Daily, constantly throughout the day.7.1.4.2. Instrumentation(1) Cleaning cloth and solution, as recommended by the CR plate manufacturer.(2) Cleaning cloth or wipe approved for use on the breast support plate and compressor plate.7.1.4.3. Methodology(1) Inspect clinical images constantly during the day for excessive artefacts attributable to dust on the imagingplates or in the readout system, defects on the imaging plates, or dirt on the breast support plate orcompression paddle. Note that images from all plates in regular use should be inspected.(2) If artefacts are detected at a level that could interfere with the diagnostic quality of the images, inspect theplates for dust or defects.(3) Record the plate inspection and/or cleaning status on the daily and weekly checklist (Chart 1 in Annex I).(a)(b)FIG. 18. Artefacts caused by (a) dust on part of an imaging plate, and (b) scrapes (horizontal arrow) and dust in the CR readout system(vertical arrows).45
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X raysdel matrixCs scintillatorLine
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QUALITY ASSURANCE PROGRAMMEFOR DIGI
Page 5 and 6: IAEA HUMAN HEALTH SERIES No. 17QUAL
Page 7 and 8: FOREWORDThe application of radiatio
Page 14: An effective QA programme is necess
Page 17 and 18: The Integrating the Healthcare Ente
Page 21 and 22: technology. Systems containing othe
Page 23 and 24: X raysTop electrodea-Se layerCharge
Page 25 and 26: dose received by inhomogeneous real
Page 27 and 28: 2.3.8.1. Soft copy displayFlat pane
Page 29 and 30: 3. ELEMENTS OF HIGH QUALITY MAMMOGR
Page 31: — The ability to mask edges of ma
Page 34 and 35: Disposal orsaleNew facility(start h
Page 36 and 37: 4.2.3. Radiographer (mammography te
Page 38 and 39: 5.2.2. Electronic versus geometric
Page 40 and 41: To allow full utilization of the di
Page 42 and 43: 5.7. ARTEFACTSWhile the incidence o
Page 44 and 45: FIG. 10. Detector crystallization.
Page 46 and 47: FIG. 13. A more subtle example of a
Page 48 and 49: FIG. 16. An example of poor collima
Page 51 and 52: 7. RADIOGRAPHER’S QUALITY CONTROL
Page 53 and 54: 7.1. DAILY TESTS7.1.1. Monitor insp
Page 55: 7.1.3. Daily flat field phantom ima
Page 59 and 60: 7.1.5. Laser printer sensitometry7.
Page 61 and 62: 7.1.6. Image plate erasure (CR syst
Page 63 and 64: FIG. 19. Modified TG18-QC pattern w
Page 65 and 66: FIG. 21. Radiologist workstation wi
Page 67 and 68: 7.2.1.6. Time frame for corrective
Page 69 and 70: 7.2.3. Weekly quality control test
Page 71 and 72: Note: It is not necessary to view t
Page 73 and 74: TABLE 7. TOLERANCES FOR IMAGING WEE
Page 75 and 76: 7.2.4.4. Interpretation of results
Page 77 and 78: 7.3.1.5. Recommendations and correc
Page 79 and 80: artefacts are typically best seen w
Page 81 and 82: 7.3.3.5. Recommendations and correc
Page 83 and 84: 7.4.1.3. Methodology(1) Annotate th
Page 85 and 86: RECORD OF DIGITAL MAMMOGRAPHY REPEA
Page 87 and 88: (3) Including examinations of at le
Page 89 and 90: 7.5. SEMI-ANNUAL TESTS7.5.1. Comput
Page 91 and 92: 8. MEDICAL PHYSICIST’S QUALITY CO
Page 93 and 94: 8.1. NOTE ON IMAGE NAMING CONVENTIO
Page 95 and 96: (16) On any randomly selected patie
Page 97 and 98: FIG. 30. Positioning of bathroom sc
Page 99 and 100: (6) The target, filter, kV, grid, d
Page 101 and 102: (2) Stack the 20 and 25 mm PMMA sla
Page 103 and 104: TABLE 13. ACCEPTABLE AND ACHIEVABLE
Page 105 and 106: 8.5. DETECTOR PERFORMANCE8.5.1. Bas
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8.5.2. Detector response and noise8
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the service engineer responsible fo
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(13) Using the annotation tool on t
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Breast supportPMMA slabBreast suppo
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(10) Place the thinner test object
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8.6. EVALUATION OF SYSTEM RESOLUTIO
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TABLE 17. ACCEPTABLE FREQUENCIES AT
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8.7. X RAY EQUIPMENT CHARACTERISTIC
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8.7.2. Incident air kerma at the en
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8.8. DOSIMETRY8.8.1. Mean glandular
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TABLE 21. ACCEPTABLE AND ACHIEVABLE
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FIG. 34. Suggested layout for ruler
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8.10. IMAGE DISPLAY QUALITYThe accu
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FIG. 35. Modified TG18-QC test patt
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8.10.1.5. Interpretation of results
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8.10.2. Monitor luminance response
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TABLE 22. MONITOR PERFORMANCE TOLER
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FIG. 38. Measurement of illuminatio
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8.11. LASER PRINTER8.11.1. Laser pr
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8.11.1.5. Recommendations and corre
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8.12.1.4. Interpretation of results
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iopsies are performed, a sink is of
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Appendix IISPECIFICATIONS OF TEST E
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TABLE 24. SPECIFICATIONS OF TEST EQ
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FIG. 40. Image acquired with a unif
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FIG. 43. The left hand image is par
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FIG. 45. A TG18-QC test pattern dis
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[29] ALSAGER, A., YOUNG, K.C., ODUK
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Annex IRADIOGRAPHER DATA COLLECTION
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Chart 2 — DIGITAL MAMMOGRAPHY (DM
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Chart 4 LASER PRINTER SENSITOMETRY
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Chart 6 — WEEKLY DISPLAY MONITOR
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Chart 7(b) WEEKLY QC TEST OBJECT:
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Chart 9 — SAFETY AND FUNCTION CHE
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Chart 11 — LASER PRINTER ARTEFACT
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Chart 13(a) — RECORD OF DIGITAL M
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Chart 14 — CR PLATE SENSITIVITY M
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Annex IIITHE MAMMOGRAPHY EXTRACTThe
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GLOSSARYair kerma. The energy depos
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image quality. The overall merit of
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CONTRIBUTORS TO DRAFTING AND REVIEW
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