1. HIGH RESOLUTION, HIGH MOLECULAR IMAGING CODED APERTURE THE DETECTOR
F. Cusanno, E. Cisbani, S. Colilli, R. Fratoni,
F. Santavenere, R. Accorsi, R. C. Lanza,
THE DETECTOR
W mask
Hamamatsu
H8500 PS-PMT
NaI(Tl) scintillator
1 mm2 x 6 mm

2. SENSITIVITY DETECTORS FOR WITH RADIONUCLIDES: OPTION
F. Garibaldi, F. Giuliani, M. Gricia, S. Lo Meo, M. Lucentini
S. Majewski, M. N. Cinti, R. Pani, R. Pellegrini
MURA 14 masks
High FoV,
1.1 mm pitch
High Resolution,
0.7 mm pitch

3. The detector is mounted for a mask-scintillator distance of b=44 mm, different support are used to perform measurements with different source-mask distance a. The minimum source-mask distance depends on a

5. Modified Uniformly Redundant Array (MURA).
The name comes from the property that all separations between holes in the pattern occur a constant number of times. The arrays are generated with the same algorithm (A) used for the URAs.
(Uniformly Redundant Array) but with the different that, G (decoding array), can not be equal to A because the autocorrelation is not a delta function. Mask (A, G) and Anti-Mask (1-A, -G), have the same ideal correlation properties. First and second order artifacts are seen to depend only on G, so adding the two images, coming from Mask and Anti-Mask the Near-Field artifacts are deleted.

6. Important Parameters for 3D Reconstruction with CA
CA Spatial Resolution
Detector pixel size determines the DoF
Mask pixel size
Pixel Dimension
n # of apertures
DoF
m Magnification factor

7. Simulations with 2D phantoms
( a = 40.1 mm )
Source-Background Uptake ratio 6:1
12 x 12 mm² Tumor
SNR =119  4
Source-Background Uptake ratio 12:1
12 x 12 mm² Tumor
SNR =135  4
Source-Background Uptake ratio 6:1
8 x 8 mm² Tumor
SNR = 90  3
Source-Background Uptake ratio 12:1
8 x 8 mm² Tumor
SNR =105  3
Source-Background Uptake ratio 6:1
5 x 5 mm² Tumor
SNR = 74  3
Source-Background Uptake ratio 12:1
5 x 5 mm² Tumor
SNR = 89  3
Source-Background Uptake ratio 12:1
3 x 3 mm² Tumor
SNR = 63  2
Source-Background Uptake ratio 6:1
3 x 3 mm² Tumor
SNR = 47  2

8. ( a = 40.1 mm )
Source-Background Uptake ratio 6:1
12 x 12 mm² Tumor
Source-Background Uptake ratio 12:1
12 x 12 mm² Tumor
SNR =135  4
Source-Background Uptake ratio 6:1
8 x 8 mm² Tumor
Source-Background Uptake ratio 12:1
8 x 8 mm² Tumor
SNR =105  3
Source-Background Uptake ratio 6:1
5 x 5 mm² Tumor
Source-Background Uptake ratio 12:1
5 x 5 mm² Tumor
SNR = 89  3
Source-Background Uptake ratio 12:1
3 x 3 mm² Tumor
SNR = 63  2
Source-Background Uptake ratio 6:1
3 x 3 mm² Tumor

9. Source-Background Uptake ratio 6:1
12 x 12 mm² Tumor
8 x 8 mm² Tumor
5 x 5 mm² Tumor

10. Measurement with point source
( a = 40.1 mm )
57Co point source
FWHM = 0.93 mm
Sensitivity=850 cps /MBq
40 cps/MBq with pinhole

11. Simulations with 3D phantoms
12 x 12 mm² Tunor, 12:1 Uptake ratio (a = 54.7 mm)
Background thickness = expected DoF (36.4 mm)
a = 54.7 mm
SNR = 100  4
a = 76.5 mm
SNR = 51  3
a = 40.1 mm
SNR = 65  3
ARTEFACTS DUE TO 3D SOURCE

13. High-FoV Mask, 8 mm source at 38 mm distance
FoV=25 mm
FoV=30 mm
FoV=35 mm
FoV=40 mm

14. High-Resolution Mask, 8 mm source at 20 mm distance
FoV=14 mm
FoV=16 mm
FoV=18 mm
FoV=20 mm

15. CONCLUSION Coded Apertures allows 3D object imaging like hot spot
Bigger detector, 100 x 100 mm2 ,2 x 2 array of H8500 or
up to 1024 channels

16. AND OUTLOOK
in a 3D background with lower uptake, 12:1 in our studies
H9500 PS-PMTs, ASICS electronics by IDEAS reading-out
The new detector could be equipped with Hamamatsu H8500 PS-PMT as well as with H9500 PS-PMTs, so a new electronics will be used, based on Front-End-Card 5053 by IDEAS