Mammography and ACR Protocols

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  • Mammography and ACR Protocols

    1. 1. George David Resident Physics SeriesResident Physics Series ACR Mammography Protocols
    2. 2. George David Mammography QC ManualMammography QC Manual • Radiologist • Clinical Image Quality • Radiologic Technologist • Medical Physicist Revised Edition, 1999Revised Edition, 1999 SectionsSections
    3. 3. George David Facility ResponsibilityFacility Responsibility • Designate One Lead Interpreting Physician
    4. 4. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • Designate one technologist responsible for QC • QC tech can delegate responsibilities to others
    5. 5. Lead Physician’s Responsibilities Lead Physician’s Responsibilities • Ensure technologists have adequate ∗ orientation » based on procedure manual ∗ training ∗ continuing education • Ensure effective QC program
    6. 6. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • Ensure availability of appropriate test equipment • Arrange staffing / scheduling to allow time for QC
    7. 7. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • provide frequent consistent positive & negative feedback to technologists about film quality & QC • Review technologist’s test results ∗ no less than every 3 months ∗ more often if inconsistent results
    8. 8. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • Select a medical physicist ∗ administers QC program ∗ performs physicist’s tests • Review physicist’s test results
    9. 9. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • Oversee or designate qualified individual to oversee radiation protection program for ∗ employees ∗ patients ∗ individuals in surrounding area
    10. 10. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • Ensure proper maintenance of records in QC procedures manual ∗ employee qualifications ∗ mammography technique / procedures ∗ quality control / safety / protection ∗ infection control
    11. 11. George David Radiologist’s ResponsibilitiesRadiologist’s Responsibilities • “The radiologist is ultimately responsible for the quality of films produced under his or her direction and bears ultimate responsibility for both proper QC testing and QA procedures in mammography.” • “The radiologist is ultimately responsible for the quality of films produced under his or her direction and bears ultimate responsibility for both proper QC testing and QA procedures in mammography.”
    12. 12. George David Physicist’s ResponsibilitiesPhysicist’s Responsibilities • Note: All physicist’s tests are toNote: All physicist’s tests are to be donebe done annuallyannually or after tubeor after tube replacement or major servicereplacement or major service
    13. 13. Physicist’s Responsibilities: Mammography Unit Assembly Evaluation Physicist’s Responsibilities: Mammography Unit Assembly Evaluation • mechanical stability / identification of sharp edges • receptor stability • locks / motions / detents • operator shielding • thickness scale accuracy • indicator lights working • technique chart posted (see next slide)
    14. 14. Physicist’s Responsibilities: Mammography Unit Assembly Evaluation Physicist’s Responsibilities: Mammography Unit Assembly Evaluation • Cassettes slide smoothly into/out of holder • Override available for auto- decompression ∗ display must indicate when auto-decompression turned off • Manual release of compression if power lost
    15. 15. George David Collimation AssessmentCollimation Assessment • x-ray light field alignment • beam does not exceed receptor by > 2% SID • compression paddle / receptor alignment at chest wall within 1% SID ∗ paddle not visible on image • Image should fill film ∗ Many units by design will not do this
    16. 16. George David Physicist’s ResponsibilitiesPhysicist’s Responsibilities • Focal Spot Performance ∗ limiting resolution pattern • kVp accuracy / reproducibility • Beam quality (HVL) ∗ minimum & maximum » minimum: patient dose » maximum: image contrast
    17. 17. Automatic Exposure Control (AEC / Phototiming) Automatic Exposure Control (AEC / Phototiming) • kVp tracking • Thickness tracking • image mode tracking (cassette sizes, w w/o grid) • automatic mode tracking ∗ unit selects kVp, target, filter • density control ∗ even steps of ~ 15-20% Density Step Changes 0 2 4 6 8 10 12 14 16 18 -5 -4 -3 -2 -1 0 1 2 3 4 5 Step %Change Series1
    18. 18. Physicist’s Responsibilities:Physicist’s Responsibilities: • Screen Uniformity ∗ compare O.D. of each cassette using phototimer • AEC Reproducibility
    19. 19. Physicist’s ResponsibilitiesPhysicist’s Responsibilities • Breast Entrance Exposure, Average Glandular Dose, ∗ RMI-156 “accreditation” phantom used for entrance exposure / average glandular dose
    20. 20. Breast Average Glandular Dose Limits Breast Average Glandular Dose Limits • 0.3 rad (300 mrads, 3 mGy) maximum per view for screen-film receptors using a grid • 0.1 rad (100 mrads, 1 mGy) maximum per view for non-grid screen-film receptors • Radiation output rate > 800 mR/sec
    21. 21. Image Quality EvaluationImage Quality Evaluation • use RMI-156 “accreditation” phantom • record ∗ fibers ∗ speck groups ∗ masses ∗ optical densities ∗ technique
    22. 22. A Poor Phantom ImageA Poor Phantom Image
    23. 23. George David Artifact IdentificationArtifact Identification • Artifact evaluation / description ∗ determination of artifact source » processor » other equipment • Done with phantom film
    24. 24. George David Physicist’s ResponsibilitiesPhysicist’s Responsibilities • Viewing conditions ∗ ambient light ∗ viewbox brightness • My experience ∗ Ambient lighting often ignored
    25. 25. Technologist’s ResponsibilitiesTechnologist’s Responsibilities • Daily ∗ darkroom cleanliness ∗ processor quality control » sensitometric data • Weekly ∗ screen cleanliness ∗ viewboxes and viewing conditions ∗ Phantom images All QC must not only be performedAll QC must not only be performed but must bebut must be documenteddocumented!! Speed 1.111.311.51 6/2/97 6/3/97 6/4/97 6/5/97 6/6/97 6/9/97 6/10/97 6/11/97 6/12/97 6/13/97 6/16/97 6/17/97 6/18/97 6/19/97 6/20/97 6/23/97 6/24/97 6/25/97 6/26/97 6/27/97 6/30/97 7/1/97 7/2/97 7/3/97 7/7/97 7/8/97 7/9/97 7/10/97 7/11/97 7/14/97 O.D. Contrast 1.481.581.681.781.88 6/2/97 6/3/97 6/4/97 6/5/97 6/6/97 6/9/97 6/10/97 6/11/97 6/12/97 6/13/97 6/16/97 6/17/97 6/18/97 6/19/97 6/20/97 6/23/97 6/24/97 6/25/97 6/26/97 6/27/97 6/30/97 7/1/97 7/2/97 7/3/97 7/7/97 7/8/97 7/9/97 7/10/97 7/11/97 7/14/97 O.D.
    26. 26. Technologist’s Responsibilities Monthly: Visual Checklist Technologist’s Responsibilities Monthly: Visual Checklist • visual checklist • SID indicator • angle indicator • locks • field light • smooth motions
    27. 27. Technologist’s Responsibilities Monthly: Visual Checklist Technologist’s Responsibilities Monthly: Visual Checklist • cassette lock ∗ Is cassette held firmed in place when tubestand tilted • Compression device & firm compression ∗ Smooth edges ∗ Holds pressure • hand switch placement • visibility • switches/ lights/ meters • cones/ collimators
    28. 28. Technologist’s Responsibilities Quarterly Technologist’s Responsibilities Quarterly • Fixer retention analysis ∗ Fixer affects archivability of films • Repeat analysis ∗ breakdown by cause » motion » positioning » technique » static » etc.
    29. 29. Semi-Annual Technologist’s Responsibilities: Darkroom Fog Semi-Annual Technologist’s Responsibilities: Darkroom Fog • must use sensitized film » partially cover previously exposed phantom film in darkroom for 2 minutes • up to .05 O.D. increase acceptable
    30. 30. Semi-annual Technologist’s Responsibilities Semi-annual Technologist’s Responsibilities Screen Film Contact • 40 lines/inch Copper mesh • subjective results • poor contact can result if time (15 minutes) not provided for air to bleed out of cassette after closing ∗ NOTE: 15 minutes between cassette loading & exposure must be provided for all clinical films to insure good contact
    31. 31. Semi-annual Technologist’s Responsibilities Semi-annual Technologist’s Responsibilities Screen Film Contact
    32. 32. Semi-Annual Technologist’s Responsibilities Semi-Annual Technologist’s Responsibilities Compression • can use bathroom scale covered with towel • 25 - 40 pounds for automatic systems • at least 25 pounds for manual compression
    33. 33. George David From the FDAFrom the FDA
    34. 34. FDA Facility & Procedure Count (as of November 1, 2007) FDA Facility & Procedure Count (as of November 1, 2007) • Total certified facilities: 8,837 ∗ Total accredited units: 13,590 • Certified facilities with FFDM units: 2,434 ∗ Accredited FFDM units: 3,644 • Total annual mammography procedures: 35,385,494
    35. 35. George David MQSA Violation LevelsMQSA Violation Levels • Level 1 (Most serious) ∗ Example: Unqualified personnel ∗ Requires written response within 15 days • Level 2 ∗ May compromise quality of service provided ∗ Example: No physics survey within 14 months ∗ Requires written response within 30 days • Level 3 ∗ Minor deviations from MQSA standards ∗ Example: missing QC records ∗ No written response required.
    36. 36. George David FDA Inspection Violations (2007)FDA Inspection Violations (2007) 1% 16% 7% 76% Level 1 (most serious) Level 2 Level 3 No Violation
    37. 37. Why Sites Failed Accreditation 2001 - 2003 Why Sites Failed Accreditation 2001 - 2003 71.1% 23.1% 5.5% 0.3% Clinical Images Only Phantom Images Only Clinical & Phantom Images Dose
    38. 38. Units Passing Accreditation 2001-2003 Units Passing Accreditation 2001-2003 86.4% 96.7% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% On 1st Attempt On 2nd Attempt
    39. 39. Units Passing Accreditation 2003 Units Passing Accreditation 2003 88.7% 88.1% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Initial Accreditation Renewel Accreditation
    40. 40. MQSAInspections Without Adverse Observations 0 10 20 30 40 50 60 70 80 90 100 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 %
    41. 41. George David What is FFDM?What is FFDM? • Fly Fishing Democratic Mothers • Far Field Dignified Marketing • Fat Farm for Dumb Maniacs
    42. 42. George David What is FFDM?What is FFDM? • Full Field Digital Mammography
    43. 43. George David How Popular is FFDMHow Popular is FFDM
    44. 44. Number of Accredited FFDM Units Number of Accredited FFDM Units 0 500 1000 1500 2000 2500 3000 3500 4000 Nov 07Nov 03
    45. 45. Is the Overall # of Mammo Units Increasing or Are these Replacement Units? Is the Overall # of Mammo Units Increasing or Are these Replacement Units?
    46. 46. Number of Accredited UnitsNumber of Accredited Units 0 2000 4000 6000 8000 10000 12000 14000 Nov 07Nov 03
    47. 47. George David The EndThe End Questions?

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