powerpoint presentationamos3.aapm.org/abstracts/pdf/99-27414-365478-110161.pdf · 7/14/2015 2 4...

7/14/2015

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Advances in CBCT for Breast Imaging

John M. Boone, Ph.D., FAAPM, FSBI, FACR

Professor of Radiology and Biomedical Engineering University of California Davis Medical Center

Sacramento, California 95817 Anaheim ● July 14, 2015 1

UC Davis Medical Center

2

Disclosures (required by UC Davis): CONSULTANT

Canadian Association of Radiologists

National Institutes of Health

RESEARCH FUNDING

Siemens Medical Systems

Telesecurity Systems

National Institutes of Health

ROYALTIES

Samsung Corporation

Lippincott Williams and Wilkins

TRAVEL FUNDING

Smarter Imaging Program, Canada

American Association of Physicists in Medicine (AAPM)

Nordic Association of Clinical Physicists

Japanese Society of Radiographers

International Commission on Radiation Units

California BCRP 7EB-0075 California BCRP 11I-0114 R01 CA•89260 R01 EB•002138-10 (BRP) R01 CA•129561 (RDB) P30 CA•093373 (CCSG) Susan G. Komen Foundation University of Pittsburgh UC Davis Bridge Funding California BCRP 20IB-0125 (Merced) R01 CA●181081

Acknowledgements:

2015 Annual AAPM Meeting / Anaheim / July 14, 2015 3

1. Introduction

2. Hardware & Software

3. Technical Performance

4. Patient Imaging

5. Clinical Performance

6. Summary


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Mammography:

Breast CT

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1. Introduction



4. Patient Imaging


6. Summary


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UC Davis Breast CT scanner development

ALBION 2004

BODEGA 2007

CAMBRIA 2012 DOHENY 2015

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Albion

Cambria

Bodega

Doheny

UC Davis

Anaheim

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Design Fabrication Integration

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Hardware component evolution

Albion 2003

Bodega 2007

Cambria 2012

Doheny 2015

x-ray tube

bearing

detector

640

W

1000

W

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Doheny: Other Components

Projection Images

Pre-processing Reconstructed CT volume

Fourier Filtering

Back Projection

Felkamp Reconstruction Module

Detector Gain Calibration

Geometric Calibration

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Calibration Software

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Detector calibration: Flat field correction

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Raw Image

ADU(x,y) = A(x,y) + B(x,y) × mA

Gain variation between dexels ≈ 48%

calibration data files

( , ) ( , )( , )

( , ) ( , )

raw raw

corr

I x y A x yI x y g

B x y A x y

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calibration data files

Detector calibration: Flat field correction

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Y

X

detector plane

Geometric calibration

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16

Physical scanner geometry Reconstruction algorithm

(xc, yc) Dx

Dy

SIC

Geometric calibration

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Feldkamp Reconstruction

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True 3D Display !

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1. Introduction



4. Patient Imaging


6. Summary


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1 1 2 2 3 3( ) (1 exp( / )) (1 exp( / )) (1 exp( / ))g t f A a t T a t T a t T

Yang et al., Computer modeling of the spatial resolution properties of a dedicated breast CT system, Med Phys 2008

detector lag

gantry rotation

detector MTF focal spot size

spatial resolution modeling

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Engineering impacts resolution

Center of FOV

Edge of FOV

Bodega

Bodega

center edge

Continuous x-ray (33 ms)

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Engineering impacts resolution

Center of FOV

Edge of FOV

Cambria

Cambria

pulsed acquisition (4 ms)

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Center of FOV

Edge of FOV

Doheny

Doheny

smaller dexels

pulsed acquisition (4 ms) + higher resolution detector Engineering impacts resolution

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total noise anatomical noise

NPS(f) = NPSa(f) + NPSq(f)

quantum noise

Detector Performance (noise)

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cone angle

coronal sagittal

2( , )

( , ) X Y

X Y

F u vNPS u v

N N D D

axial

Detector Performance (NPS evaluations)

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Slice Thickness

x-ray tube mA

RECON algorithm

Shepp-Logan

RECON algorithm

Ramp

Near-Neigh

Bilinear

Yang et al., Noise power properties of a cone beam CT system for breast cancer detection, Med Phys. 2008

Noise Power Spectrum (NPS) measurements (Bodega)


1. Introduction



4. Patient Imaging


6. Summary


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Phantom Imaging

Clinical Imaging

1. Over 600 women on UC Davis scanners

2. Suspicion of BC (BIRADS 4 or 5)

3. 16 second scan (breath hold)

4. 500 projection images acquired (1024 x 768)

5. About 200 have had contrast injection

6. Radiation dose same as 2V mammography

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Funded for 400 more

~10 sec on new scanner

400 – 800 views on new scanner (2048 x 1536)

Developing AEC for Doheny

400 more to go, with DCE-MRI comparison also

Contralateral (normal) breasts imaged as well

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296

January 2005

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bCT (no injected contrast)

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34 Pt 160

Contrasted Enhanced breast CT pre

pre post

post

Malignant

benign

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Dedicated breast PET-CT imaging system

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1. Introduction



4. Patient Imaging


6. Summary


2010

DHU AUC = 0.87

Shadi Aminololama-Shakeri, M.D.

Prospective Clinical Trial 105 patients /103 lesions (BIRADS 4 or 5) imaged on VCO mammo / tomo / CE-bCT all biopsied

2 Radiologists Rated Lesions using a 0 to 10 Conspicuity Score 0 = not seen 10 = excellent

malignant

benign

microcalcifications masses

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18 27

31

one-way ANOVA with correction for multiple comparisons

total 45 58

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mammo tomo CE-bCT mammo tomo CE-bCT

Increased sensitivity

Increased specificity

mammo tomo CE-bCT mammo tomo CE-bCT

with radiologist analysis, Az = 0.96

b slope

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NPS(f) = NPSa(f) + NPSq(f)

bCT, Tomo, and Mammo Comparisons

breast CT mammography tomosynthesis

N = 23 pts 1000 ROIs per

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PWMF Observer Performance Analysis

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FT{S(x,y)}

PS(x,y) PWMF = FT-1

Pre-whitened Matched Filter

mammography

breast CT

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Breast CT

“Mammo”

PWMF Observer

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(a) (b)

Human Observer Study: 2-Alternative Forced Choice Design

CT images projection images

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3 radiologists / 6 physicists

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Breast CT

“Mammo”

PWMF Observer

Radiologist Observers average of 3


1. Introduction



4. Patient Imaging


6. Summary


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• Breast CT shows promise by all comparative metrics for mass lesions (beta, AUC, %correct)

• Observer performance results show enhanced mass lesion detection

• Computer observer (PWMF)

• Radiologist observers

• Breast CT (Koenig) FDA approved for diagnostic breast imaging Feb 2015

• microcalcification detection performance needs to be equivalent to mammography for bCT screening

• CE-breast CT is virtually identical as DCE-breast MRI



John M. Boone, Ph.D., FAAPM, FSBI, FACR

Professor of Radiology and Biomedical Engineering University of California Davis Medical Center

Sacramento, California 95817

University of California Davis

Breast Tomography Project


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1. Introduction



4. Patient Imaging


6. Summary


bCT, Tomo, and Mammo Comparisons

breast CT mammography tomosynthesis

N = 23 pts 1000 ROIs per

breast CT mammo

b b

Breast CT images

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axial view (~cc)

slice thickness (mm)

~10 mm

Tomo

dis

k d

iam

eter

(m

m)

tomographic angle

measured data on the breast CT system

Breast CT Images

Mammo

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Tomosynthesis Images

0 mm

55 mm

Hardware component evolution

Albion 2003

Bodega 2007

Cambria 2012

Doheny 2015

x-ray tube

bearing

detector

comet comet Varian M1500 Varian M1503

Kollmorgen Kollmorgen Yaskawa Yaskawa

Varian 4030CB TFT

Varian 4030CB TFT

Varian 4030CB TFT

Dexela 2923 CMOS

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