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4.2.3. Radiographer (mammography technologist)The responsibilities of the radiographer include:(1) Ensuring that the QC tests are performed, interpreted and recorded appropriately. This is best achieved whenone radiographer assumes overall responsibility for QC matters and is able to train others to assist in QCactivities.(2) Recording imaging problems.(3) Undertaking additional continuous education courses in mammography, including digital mammography.4.2.4. Medical physicistThe medical physicist is a person trained in medical physics and certified as a medical physicist according tothe applicable programme in the Member State, if such a programme exists. Guidelines for the training of a medicalphysicist are given in appendix I of Ref. [34].The minimum requirements for an individual delegated to carry out the annual medical physicist’s QC testsdescribed in this publication are:(1) Training in radiation safety;(2) Training in the physics of mammography, in particular digital mammography;(3) Practical training in testing digital mammography equipment.The responsibilities of the medical physicist include:(1) Advising the facility on the safe and effective use of X rays for mammography. This includes image qualityand radiation protection of the patient and personnel.(2) Advising the facility on equipment for digital mammography including the PACS. In some circumstances, thephysicist may work as a liaison between the facility and a specialist in PACS.(3) Conducting tests to ensure the safety and proper performance of equipment used in mammography. Theseinclude acceptance, commissioning and routine QC tests.(4) Providing oversight and advice to the radiographer who carries out the radiographer’s component of the QCprogramme.24
5. CLINICAL CONSIDERATIONSFOR DIGITAL MAMMOGRAPHY5.1. INTRODUCTIONThe transition from film to digital mammography is progressing rapidly. The DMIST [3] demonstrated theimproved accuracy of digital over film for asymptomatic women under 50 years of age, pre- and peri-menopausalwomen and those women having at least 50% dense fibroglandular breast tissue.There are both advantages and limitations to digital mammography versus screen film mammography.5.1.1. Main clinical implications of digital mammographyDigital mammography can provide high quality images as well as the ability to adjust the presentation so thatclinical interpretation may be improved in dense breasts. The time required by the radiographer to conduct anexamination is generally decreased, allowing greater patient throughput. There is, however, an increase in the timerequired for image interpretation, but this is becoming less significant. The elimination of film processing removescost, hazard, film processing artefacts and losses due to films becoming stuck in the processor.The images can be centrally stored on a PACS and accessed from many locations. An RIS in conjunction withan HIS in the facility can be used to schedule patients, upload demographic information to the acquisitionworkstation and track the patient workflow.5.2. IMAGE ACQUISITION5.2.1. Differences in patient positioning and radiographic exposureWhile positioning of the breast is similar to that in screen film mammography, with DX systems it may bemore difficult for radiographers, especially initially, as the breast support is often thicker and may extend a fewcentimetres beyond the image sensor, and in some cases a large detector has to be used for smaller patients.Nonetheless, overall patient throughput can potentially increase with digital acquisition, allowing a facility to reviseits workload and workflow.Generally, there is the possibility of decreasing the dose to the breast, although this does not necessarilyextend to CR systems. First, digital detectors have increased exposure latitude compared with screen film systems,which means that there are fewer repeat exposures. Second, the use of a higher energy beam technique and anincreased DQE will lead to lower absorbed breast dose, but a balance must be maintained between reduction of doseand image quality because insufficient radiation dose to the image receptor results in noisy images, makingidentification of microcalcifications more difficult. An excessively high dose might not be noticed because itprobably would not cause image quality problems, unlike with screen film, where the image overexposure would beobvious. Third, digital detectors have lower limiting spatial resolution compared with screen film, which may limitthe ability of the radiologist to characterize the morphology of calcifications; however, increased DQE and imageprocessing may compensate for this somewhat.As with screen film mammography, it is possible for the quality obtained with digital mammography to bepoor if the system is poorly designed, not set up properly, or not serviced or cleaned appropriately.Individual exposure factors and other technical details can be more readily assessed and analysed for DXunits via records of technique factors. It is more difficult to extend this to CR units, where special software andhardware (e.g. a Livingston CR Protocol Bridge (www.livingstonproducts.com/mammo/CRBridge.html)) may berequired.25
Page 1 and 2: X raysdel matrixCs scintillatorLine
Page 3 and 4: 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 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 and 56: 7.1.3. Daily flat field phantom ima
Page 57 and 58: 7.1.4. Visual inspection for artefa
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
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(3) Including examinations of at le
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7.5. SEMI-ANNUAL TESTS7.5.1. Comput
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8. MEDICAL PHYSICIST’S QUALITY CO
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8.1. NOTE ON IMAGE NAMING CONVENTIO
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(16) On any randomly selected patie
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FIG. 30. Positioning of bathroom sc
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(6) The target, filter, kV, grid, d
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(2) Stack the 20 and 25 mm PMMA sla
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TABLE 13. ACCEPTABLE AND ACHIEVABLE
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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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