GeorgeDavid
Resident Physics SeriesResident Physics Series
ACR Mammography Protocols
GeorgeDavid
Mammography QC ManualMammography QC Manual
• Radiologist
• Clinical Image Quality
• Radiologic Technologist
• Medical Physicist
Revised Edition, 1999Revised Edition, 1999
SectionsSections
GeorgeDavid
Facility ResponsibilityFacility Responsibility
• Designate One Lead Interpreting Physician
GeorgeDavid
Radiologist’s ResponsibilitiesRadiologist’s Responsibilities
• Designate one technologist responsible for QC
• QC tech can delegate responsibilities to others
Lead Physician’s Responsibilities
Lead Physician’s Responsibilities
• Ensure technologists have adequate orientation
» based on procedure manual
training continuing education
• Ensure effective QC program
GeorgeDavid
Radiologist’s ResponsibilitiesRadiologist’s Responsibilities
• Ensure availability of appropriate test equipment
• Arrange staffing / scheduling to allow time for QC
GeorgeDavid
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
GeorgeDavid
Radiologist’s ResponsibilitiesRadiologist’s Responsibilities
• Select a medical physicist administers QC program performs physicist’s tests
• Review physicist’s test results
GeorgeDavid
Radiologist’s ResponsibilitiesRadiologist’s Responsibilities
• Oversee or designate qualified individual to oversee radiation protection program for employees patients individuals in surrounding area
GeorgeDavid
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
GeorgeDavid
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.”
GeorgeDavid
Physicist’s ResponsibilitiesPhysicist’s Responsibilities
• Note: All physicist’s tests are to Note: All physicist’s tests are to be done be done annuallyannually or after tube or after tube replacement or major servicereplacement or major service
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)
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
GeorgeDavid
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
GeorgeDavid
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
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
% C
han
ge
Series1
Physicist’s Responsibilities:Physicist’s Responsibilities:
• Screen Uniformity compare O.D. of each cassette using
phototimer
• AEC Reproducibility
Physicist’s ResponsibilitiesPhysicist’s Responsibilities
• Breast Entrance Exposure, Average Glandular Dose, RMI-156 “accreditation” phantom used for entrance
exposure / average glandular dose
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
Image Quality EvaluationImage Quality Evaluation• use RMI-156 “accreditation”
phantom
• record fibers speck groups masses optical densities technique
A Poor Phantom ImageA Poor Phantom Image
GeorgeDavid
Artifact IdentificationArtifact Identification
• Artifact evaluation / description determination of artifact source
» processor
» other equipment
• Done with phantomfilm
GeorgeDavid
Physicist’s ResponsibilitiesPhysicist’s Responsibilities
• Viewing conditions ambient light viewbox brightness
• My experience Ambient lighting
often ignored
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 performed All QC must not only be performed but must be but must be documenteddocumented!!
Speed
1.11
1.31
1.51
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
.
Technologist’s ResponsibilitiesMonthly: Visual Checklist
Technologist’s ResponsibilitiesMonthly: Visual Checklist
• visual checklist• SID indicator• angle indicator• locks• field light• smooth motions
Technologist’s ResponsibilitiesMonthly: Visual Checklist
Technologist’s ResponsibilitiesMonthly: 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
Technologist’s ResponsibilitiesQuarterly
Technologist’s ResponsibilitiesQuarterly
• Fixer retention analysis Fixer affects archivability of
films
• Repeat analysis breakdown by cause
» motion» positioning» technique» static» etc.
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
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
Semi-annual Technologist’s Responsibilities
Semi-annual Technologist’s ResponsibilitiesScreen Film Contact
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
GeorgeDavid
From the FDAFrom the FDA
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
GeorgeDavid
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.
GeorgeDavid
FDA Inspection Violations (2007)FDA Inspection Violations (2007)
1%16%
7%
76%
Level 1 (most serious)Level 2Level 3No Violation
Why Sites Failed Accreditation2001 - 2003
Why Sites Failed Accreditation2001 - 2003
71.1%
23.1%
5.5%
0.3%
Clinical Images Only
Phantom Images Only
Clinical & PhantomImagesDose
Units Passing Accreditation2001-2003
Units Passing Accreditation2001-2003
86.4%
96.7%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
On 1st Attempt On 2nd Attempt
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
MQSA Inspections Without Adverse Observations
0102030405060708090
100
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
%
GeorgeDavid
What is FFDM?What is FFDM?
• Fly Fishing Democratic Mothers
• Far Field Dignified Marketing
• Fat Farm for Dumb Maniacs
GeorgeDavid
What is FFDM?What is FFDM?
• Full Field Digital Mammography
GeorgeDavid
How Popular is FFDMHow Popular is FFDM
Number of Accredited FFDM Units
Number of Accredited FFDM Units
0
500
1000
1500
2000
2500
3000
3500
4000
Nov 07Nov 03
Is the Overall # of Mammo Units Increasing
orAre these Replacement Units?
Is the Overall # of Mammo Units Increasing
orAre these Replacement Units?
Number of Accredited UnitsNumber of Accredited Units
0
2000
4000
6000
8000
10000
12000
14000
Nov 07Nov 03
GeorgeDavid
The EndThe End
Questions?