1. Comparison of Scintimammography and Dedicated Emission Mammotomography
Martin P. Tornai, Caryl N. Brzymialkiewicz, Spencer J. Cutler, Priti Madhav
Multi-Modality Imaging Laboratory
Department of Radiology
Department of Biomedical Engineering
Duke University Medical Center, Durham, NC, USA
Supported by NIH Grant RO1-CA96821 and DAMD

2. Overview
Develop a “universal” breast phantom for emission and/or transmission imaging
Needs to be compressible for uncompressed and partial compression imaging comparisons
Needs to accommodate inserted lesions
Needs to have physical attributes similar to human torso
Make direct comparison of uncompressed breast SPECT and compressed scintimammography
Develop and compare various fillable lesion sizes
Compare different activity concentrations

3. Solid State Imaging Detector
Detector CdZnTe
Density 5.78 g/cm3
Effective Z 49
Elements 64 x 80
Crystal Dimensions 2.3 x 2.3 x 5 mm3
Pixel Size 2.5 x 2.5 mm2
FOV 16 x 20 cm2
Sensitivity 38 cts/sec/MBq
Uniformity (post corr) < ±4%
Energy Resolution 140 keV
20.0 cm
16.0 cm
6.6 cm
LumaGEM™ 3200-S
(Gamma Medica Inc.)

4. Prototype Emission Mammotomograph
Anthropomorphic torso and breast phantoms
(Radiology Support Devices, Inc.)
Integrated Gamma Camera
(Gamma Medica, Inc.)
Polar Tilt, 
ROR
Azimuth, 
Radius of Rotation control (Newport Corp., Sanyo-Denki)
Rotation stage and goniometer
(Newport Corp.)

5. Compressible Breast Phantom & Chest Plate
Fill port
3 cm f insertion port
Fillable Volume: ~700 mL
Nipple-Chest: cm
Medial-Lateral: cm
Superior-Inferior: cm
“Skin” thickness: cm
(Radiology Support Devices, Inc.)

6. Compressible Breast Phantom & Lesions
Digital X-ray image
Stems: 1.6 mm OD x 4.5 cm polyethylene 70
500
140
300
Lesions
Volume “Diameter”
(microL) (mm)
40 +/
70 +/
140 +/
300 +/
500 +/ 40
140
140
(Harvard Apparatus)

7. Scintimammography Acquisition Parameters
Lesion Concentration 40 microCi / mL
20X clinical !
Lesion : Background Inf., 12 : 1, 7 : 1, 3 : 1
View Lateral (single view)
Compression 12 cm, 9 cm, 6 cm
Acquisition Time 10 min (equivalent)

8. Breast Compression
4 cm
12 cm
9 cm
6 cm
Cranio-Caudal Lateral

9. Scintimammography (Planar) Projections
Compression Thickness
9cm 7 : 1
9cm 12 : 1
9cm 3 : 1
12 cm
9 cm
6 cm
12 : 1
7 : 1
Leaky Phantom
3 : 1

10. Scintimammography: Effects of Compression
12 : 1 Concentration Ratio

11. Scintimammography: Effects of Activity Concentration
6 cm Compression

12. SPECT Acquisition Parameters
20X clinical !
Lesion Concentration 40 microCi / mL
Lesion : Background Ratios Inf., 12 : 1, 7 : 1, 3 : 1
Mammotomography (q = 0 – 360)
Orbits: Vertical Axis of Rotation (VAOR)
ROR = 6.6 cm, f = 0 deg
Tilted Parallel Beam (TPB)
ROR = 5.2 cm, f = 45 deg
3 Lobed Sinusoid on Hemisphere (ProjSine)
ROR = 2.8 – 5.2 cm, f = 15 – 45 deg
Angular Increment : 2.8 deg
Acquisition Time : 10 min (equivalent)
Details about orbits and sampling on POSTER #
M2-269

13. Mammotomography Orbits
VAOR
TPB45
ProjSine 0o
30o
60o
90o
Camera
Tilt ()
Details about orbits and sampling on POSTER # M2-269

14. Mammotomography Reconstructions
12 : 1 Concentration ProjSine Data
Transverse
Sagittal
Maximum Intensity Projection (MIP)
OSEM reconstruction with 5 iterations, 8 subsets, calculated attenuation correction, 3D Hann filtration with fc = 0.8*Nyquist

15. Mammotomography MIPs 300 uL 500 uL 40 uL 70 uL 140 uL VAOR TPB45
ProjSine
12 : 1
7 : 1
3 : 1

16. SPECT SNR & Contrast 12 : 1 Concentration Data
ROI data from OSEM reconstruction with 3 iterations, 8 subsets, calculated attenuation correction, 3D Hann filtration with fc = 0.8*Nyquist

17. SPECT & Scintimammography SNR & Contrast

18. Conclusions
Developed a compressible breast+chest phantom useful for comparative emission breast imaging with physical limitations more consistent with a human torso
Measured various lesion sizes, locations (esp. near chest wall), and activity concentrations relative to backgrounds
Compared compressed breast, planar scintimammography with uncompressed breast SPECT mammotomography
Scintimammography has limited viewable breast volume towards the anterior chest wall
Under a wide range of “low noise” measurement conditions:
More lesions, lesion sizes, and (3D) lesion locations can be detected (and thus quantitated) with dedicated emission mammotomography than with compressed breast scintimammography

19. Multi-Modality Imaging Lab