DIGITAL MAMMOGRAPHY:
PHYSICIAN’S PERSPECTIVE
ACKNOWLEDGEMENTS
• Thanks to:
to:
2008 Annual AAPM Meeting
Houston, TX
July 31, 2008
JAY PARIKH, MD, FRCP(c),
FRCP(c), CPE, FSBI, FACPE
Medical Director
Women’
Women’s Diagnostic Imaging Center
Swedish Cancer Institute
CREDENTIALS
• Can spell digital
• Have used a digital
camera
– AAPM
• Special Thanks:
Thanks:
– Kalpana Kanal,
Kanal, PhD, DABR
CREDENTIALS
• Certified by ABR,
FRCP, ACR
• Fellowship in
breast imaging
• Do 100% breast
• Have a digital unit
on site
1
It works!
Thank You!
DISCLOSURE
• Hologic:
Hologic:
– NonNon-paid member, scientific
advisory panel
OBJECTIVES
• (1) To review clinically relevant functional
components of digital mammography.
• (2) To introduce some of the advanced
applications of digital mammography.
• Thanks to:
to:
– Grady Hartzog,
Hartzog, M.D.
2
OBJECTIVES
OBJECTIVES
• (1) To review clinically relevant functional
components of digital mammography.
• (3) To discuss some barriers to widespread
clinical use of digital mammography.
• (2) To introduce some of the advanced
applications of digital mammography.
• (4) To review data from clinical trials
regarding digital mamography.
mamography.
OBJECTIVES
• (3) To discuss some barriers to widespread
clinical use of digital mammography.
• (4) To review data from clinical trials
regarding digital mammography.
3
DIGITAL
MAMMOGRAPHY
2007 ACS STATS
WHY DIGITAL?
• 1 in 7 cumulative lifetime risk
• >178,000 new invasive cancers
• >40,000 deaths from breast cancer
INTRODUCTION
SCREENING
RADIOLOGIST
SMALLER
CANCERS
PRIMARY
DIAGNOSTICIAN
PATIENT
SURVIVAL
SFM: QED
• Randomized
control trials
• 2 years before
palpable
• ACR, ACS, AMA
TREATMENT
OPTIONS
4
SFM - LIMITATIONS
•
•
•
•
•
DENSE BREAST MULTICENTRIC CA
Mature technology
FN 1010-30%
Dense tissue
PPV 55-40%
Anything better?
DIGITAL
MAMMOGRAPHY
WHY DIGITAL?
FUNCTIONAL
COMPONENTS
5
FUNCTIONAL
COMPONENTS
IMAGE ACQUISITION
DIGITAL :
• (1) Image Acquisition
• (2) Image Processing
• (3) Image Display
SFM: ALL BY FILM!
Photons -->
--> Detector
-->
--> Electrical
SFM:
Photons -->
-->
Light
-->
--> Latent image
IMAGE ACQUISITION
DIGITAL :
Photons -->
--> Detector -->
--> Electrical
• dynamic range 1000:1
• higher contrast ; dense breast
• spatial <= SFM
6
SECOND OPINION FOR CA++
SECOND OPINION FOR CA++
7
IMAGE PROCESSING
• Alter contrast
• Alter brightness
• Enlarge areas
• Reduce repeats
• Reduce radiation dose
8
IMAGE DISPLAY
(1) Hard - copy
Laser print film
(2) Soft - copy
Cathode ray tube
monitor
HARD COPY
•
•
•
•
Installation printer
Film expense
Storage cost and space
One window/level
image
• Tangible record
• No processor errors
9
OPERATIONAL
• Tech work station
• Reading work
station
• Film comparisons
• Storage area
SOFT COPY
•
•
•
•
•
Expense of monitors
Professional training
Tech support
Comparisons
SFM viewboxes
• Multiple windows
• No digitizer for CAD
10
HARD COPY vs
SOFT COPY
• International Development Group
• 28 images - histologically proven Ca++ and
masses
• 3 units (GE, Fischer, LoRad)
LoRad)
• 12 radiologists compared SFM to digitized
FFD images
Pisano E et al. Radiology 2000; 216: 820-830
LCD vs CRT
HARD COPY vs
SOFT COPY
•
•
•
•
Screening: SFM preferred to digitized
Masses: Printed digitals preferred to screening
CA++: No processed digital preferred to SFM
When digital images preferred to SFM, selected
processing.
– Thus, softsoft-copy display preferred.
Pisano E et al. Radiology 2000; 216: 820-830
LCD vs CRT
• Expensive
• Luminescence
• Lower weight
• Grainy images
• Life expectancy
• Smaller volume
• Technology for FFDM
• Lesion conspicuity
• Reduced heat load
11
DIGITAL
MAMMOGRAPHY
ADVANCED
APPLICATIONS
WHY DIGITAL?
FUNCTIONAL
COMPONENTS
ADVANCED
APPLICATIONS
(1) Telemammography
(2) CAD
(3) New modalities
Parikh JR. Digital Mammography: Current
Capabilities and Obstacles. JACR 2005
TELEMAMMOGRAPHY
• Rapid digital image
transfer between
sites
• Enabled by softsoftcopy transfer
Kelly M, Parikh JR, Shaw KK, Hallam PS. Mobile
Digital Telemammography. Sem Breast Dis 2006
12
TELEMAMMOGRAPHY
STRENGTHS
• Mobile mammo - RT
can check films
• OffOff-site supervision
and reads
• OnOn-line reads
• Expert reads in group
• DoubleDouble-reads
• Second opinions
TELEMAMMOGRAPHY
ISSUES
•
•
•
•
•
•
Image transfer quality
Lines for transfer
Costs
Patient privacy issues
Liability
Standards & guidelines
CAD / SFM
•
•
•
•
Digitized hardcopy software been around
Been used with SFM
3 companies approved by FDA
Retrospective / prospective studies
– increased cancers
– increased recalls; increased FP
• Reimbursed
13
“DIGICAD”
“DIGICAD” - ISSUES
• Operational headaches
• Direct softcopy software is key
• Efficient
• Less expensive? (No hardware)
CAD / SFM - ISSUES
• How many attorneys
does it take to screw in
a light bulb?
• How many can you
afford?
– installation
– process issues
– professional training
•
•
•
Resistance by staff
Reimbursement variable
MedicoMedico-legal
NEW IMAGING
MODALITIES
(1) Stereomammography
(2) ContrastContrast-enhanced DM
(3) Tomosynthesis
(4) DualDual-energy subtraction
14
STEREOMAMMO
•
•
•
•
>=2 images obtained at different angles
Images fused together
Perceive relative depth
Similar to images of stereotactic biopsy
CONTRASTENHANCED DM
•
•
•
•
Angiogenesis = neovascularity
Enhancement profile
Similar to MRI
Spatial resolution DM greater than MRI
Angiogenesis: The Basics
Genetic mutations
cause a cell
to become cancerous
Small tumor
Chemical
signal
Growing
tumor
Growing
Capillaries
Nutrients
from blood
Cancer cells
migrate to
other parts of
the body
Source: Time Magazine, May 1998
15
CONTRAST ENHANCED
DIGITAL MAMMOGRAPHY
• Adjunctive Imaging
– Positive/Negative Predictive
– Sens/Spec
Sens/Spec
• Extent of disease
• High Risk Screening
– Sens/Spec
Sens/Spec
– False + ????
Parikh JR, Porter BA ATL Case Studies
CONTRASTENHANCED DM
• Jong,
Jong, Yaffe et al
– ContrastContrast-enhanced Digital Mammography: Initial
Clinical Experience
– Radiology 2003; 228:842228:842-850
Digital XX-ray Breast Angiography
• Outline of Procedure
–
–
–
scout image
injection of 100mL Omnipaque 300
images 2 to 5 taken at times 1 min., 3 min., 5 min. and
7min. from start of injection
• Lewin, et al
– DualDual-Energy ContrastContrast-enhanced Digital Subtraction
Mammography
– Radiology 2003; 229:261229:261-268
• Image acquisition
– Direct Subtraction
– Dual Energy
• Image Processing
– registration
– logarithmic subtraction
– smoothing
Courtesy : Yaffe / Parisky
16
Patient With Benign Lesion (Fibrocystic Change)
Digital Subtraction Iodine Imaging of the Breast
Precontrast
Compressed
Breast
1 min
Scout
PostContrast
Contrast
Agent
T
I1
I2
Logarithmic subtraction:
lnI2 –lnI1 = t(µ−µ1)
Courtesy : Yaffe / Parisky
Enhancement Kinetics
30
25
Subtracted Images
Linear subtraction:
I2-I1 = I0e-µt(et(µ1−µ) − 1)
5 min
Lesion Mean - Tissue Mean in
I2 = I0e-µ(T-t)-µ1t
I1 = I0e-µt
20
15
10
5
0
0
1
2
3
4
5
6
7
8
Time (minutes)
Courtesy : Yaffe / Parisky
Patient With Malignant Lesion (IDC)
DUAL-SUBTRACTION
1 min
Scout
• Acquisition of 2 images in which effective
energy of the detected radiation differs
• Single exposure; stacked detectors
Enhancement Kinetics
30
Subtracted Images
Lesion Mean - Tissue Mean in
5 min
• Mask undesirable irrelevant material
• Preserve contrast in relevant structures
20
10
0
0
1
2
3
4
5
6
7
8
Time (minutes)
Courtesy : Yaffe / Parisky
17
TOMOSYNTHESIS
• Digital form of tomography
• Minimal added time and added radiation
• Rad source moves in a stepstep-wise arc above
detector
• Planes above and below are blurred
– makes lesion conspicuous
Courtesy: Hologic
18
Selenia Mammogram
Biopsy proven cancer
Selenia Tomosynthesis
Selenia Mammogram
Selenia Tomosynthesis
Mammographically occult biopsy proven cancer
19
Selenia Mammogram
Selenia Tomosynthesis
Mammographically occult biopsy proven cancer
Selenia Mammogram
Selenia Tomosynthesis
Benign. Superimposed parenchyma
Selenia Mammogram
Selenia Tomosynthesis
Benign cyst that went to biopsy
20
Selenia Mammogram
Selenia Tomosynthesis
Benign cyst that went to biopsy, not visible in FFDM MLO
DIGITAL
MAMMOGRAPHY
WHY DIGITAL?
FUNCTIONAL
COMPONENTS
ADVANCED
APPLICATIONS
BARRIERS
BARRIERS
•
•
•
•
•
•
(1)
(2)
(3)
(4)
(5)
(6)
Cost
Operational - space, setset-up
Storage
Resistance to change
MQSA / FDA
Clinical trials data
Parikh JR. Digital Mammography: Current
Capabilities and Obstacles. JACR 2005
21
COST
• Unit, Plate
• Ancillary
– monitors
– printer
• Space / electrical
• Service support
• Professional Education
OPERATIONAL
OPERATIONAL
• Tech work station
• Reading work
station
• Film comparisons
• Scheduling
TECH ACQUISITION
STATION
22
OPERATIONAL
• Tech work station
• Reading work
station
• Film comparisons
• Storage area
OPERATIONAL
• Tech work station
• Reading work
station
23
STORAGE
• 4 views = 3535-216 MB
– CEDM
– DIG TOMO
• Compression techniques
• Separation breast pixels
• PACS
CHANGE
• Admins don’
don’t want the
headache
• MD’
MD’s resistant to soft
copy monitors
• MedicoMedico-legal issues
• Only constant in health
care is change
MQSA / FDA
• Each unit will have separate FDA/ MQSA
requirements
• Costs
• “Silo effect”
effect”
CONSENSUS PANEL!
Parikh JR, Fanus D. Implementing Digital Quality
Control in a Breast Center. JACR 2004
24
DIGITAL
MAMMOGRAPHY
WHY DIGITAL?
FUNCTIONAL
COMPONENTS
ADVANCED
APPLICATIONS
BARRIERS
CLINICAL
TRIALS
CLINICAL TRIALS
• RCT only way to prove reduction in
mortality from early detection
• Ethically not possible
• Inferred by comparing SFM to FFD
– like manufacturers to get FDA approval
25
CLINICAL TRIALS
Trial
Article
FFDM
n
AGE
PPV
Detection
Rate
Recall
Rate
DMIST (455 days)
4945 40-69 (Screening) FFDM = 60% FFDM = 11.5%
Colorado Radiology 2001; GE
FFDM = 3.7%, SFM = 63% SFM = 13.8%
2000D
218:873-80
/ Mass
SFM = 3.2%
Oslo I
Oslo II
ACRIN
DMIST
Modality
Sensitivity
Specificity
PPV
FFDM
0.49
0.97
0.12
SFM
0.35
0.98
0.07
0.47
0.97
0.10
FFDM = 0.62% FFDM = 4.6%
(Biopsy)
3683 50-69
Radiology 2003; GE
FFDM = 39%, SFM = 0.76% SFM = 3.5%
2000D
229: 877-884
SFM = 46%
Women <50
Radiology 2004; GE 25263 45-69 (Abn Mammo)
50-69
232: 197-204
2000D
50-69
FFDM = 0.83%
FFDM = 21.6% SFM = 0.54%
SFM = 22.1%
45-49
45-49
FFDM = 0.27%
FFDM = 7.1% SFM = 0.22%
SFM = 7.4%
Pre and perimenopausal
FFDM
SFM
0.38
0.98
0.09
Heterogeneously
Dense or Dense
FFDM
0.38
0.97
0.10
SFM
0.36
0.97
0.10
NEJM 2005;
353-
Fischer 42760 40-70
, Fuji,
GE,
Hologic
?
50-69
FFDM = 3.8%
SFM = 2.5%
45-49
FFDM = 3.7%
SFM = 3.0%
?
?
NEJM 2005; 353
DMIST (455 days)
DMIST (455 days)
Modality
Sensitivity
Specificity
PPV
FFDM
Modality
Sensitivity
Specificity
PPV
FFDM
0.49
0.97
0.12
SFM
0.35
0.98
0.07
Pre and perimenopausal
FFDM
0.47
0.97
0.10
Heterogeneously
Dense or Dense
0.49
0.97
0.12
SFM
0.35
0.98
0.07
Pre and perimenopausal
FFDM
0.47
0.97
0.10
SFM
0.38
0.98
0.09
SFM
0.38
0.98
0.09
Heterogeneously
Dense or Dense
FFDM
0.38
0.97
0.10
FFDM
0.38
0.97
0.10
SFM
0.36
0.97
0.10
SFM
0.36
0.97
0.10
Women <50
Women <50
NEJM 2005; 353
NEJM 2005; 353
26
DMIST (455 days)
Modality
Sensitivity
Specificity
OBJECTIVES
PPV
FFDM
0.49
0.97
0.12
SFM
0.35
0.98
0.07
Pre and perimenopausal
FFDM
0.47
0.97
0.10
SFM
0.38
0.98
0.09
Heterogeneously
Dense or Dense
FFDM
0.38
0.97
0.10
SFM
0.36
0.97
0.10
Women <50
• (1) To review clinically relevant functional
components of digital mammography.
• (2) To introduce some of the advanced
applications of digital mammography.
NEJM 2005; 353
OBJECTIVES
OBJECTIVES
• (1) To review clinically relevant functional
components of digital mammography.
• (3) To discuss some barriers to widespread
clinical use of digital mammography.
• (2) To introduce some of the advanced
applications of digital mammography.
• (4) To review data from clinical trials
regarding digital mamography.
mamography.
27
IS FFDM READY FOR
PRIME TIME?
OBJECTIVES
• (3) To discuss some barriers to widespread
clinical use of digital mammography.
• (4) To review data from clinical trials
regarding digital mammography.
•
•
•
•
Getting close..…
close..….
DMIST helped
Workflow issues
Manufacturers stuck - need to see profits
• But…
But….
IT’S COMING!!
Parikh JR. Digital Mammography: Current
Capabilities and Obstacles. JACR 2005
USA - FFDM UNITS AND FACILITIES
x
3
Courtesy Penny Butler, ACR/ FDA website
4
28
FIND X
HERE IT IS!
x
3
x
3
4
4
Thank You!
29
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