DocumentCode :
1388875
Title :
A discrete scintillation camera module using silicon photodiode readout of CsI(TI) crystals for breast cancer imaging
Author :
Gruber, G.J. ; Moses, W.W. ; Derenzo, S.E. ; Wang, N.W. ; Beuville, E. ; Ho, M.H.
Author_Institution :
Lawrence Berkeley Nat. Lab., California Univ., Berkeley, CA, USA
Volume :
45
Issue :
3
fYear :
1998
fDate :
6/1/1998 12:00:00 AM
Firstpage :
1063
Lastpage :
1068
Abstract :
The authors characterize a 3×4 element imaging array consisting of 3×3×5 mm3 CsI(TI) scintillator crystals individually read out by 3×3 mm2 PIN silicon photodiodes. The array is a prototype for larger modules (16×16 element) for use in single photon breast cancer imaging. The photodiode output signals are amplified with a 16 channel custom IC (<3 mm on a side), after which a “Winner Take All” (WTA) custom IC (<3 mm on a side) identifies the crystal of interaction based on relative signal amplitudes. The compact nature of these readout electronics will simplify the construction of larger imaging arrays. The photodiodes were developed for low leakage current (~50 pA) and yield a total electronic noise of 390 e- full width at half maximum (fwhm) at a shaping time of 8 μs, with signal levels of 6600 e- for the 140 keV emissions of 99mTc. Array pixels demonstrate an average room temperature energy resolution of 10.7±0.6% fwhm for these 140 keV gamma rays. The authors observe an intrinsic spatial resolution of 3.3 mm fwhm for a 2.5 mm diameter 57Co beam on the face of the crystal array, and a system resolution of 5.9 mm fwhm for a 2 mm diameter uncollimated 99mTc source viewed through a high resolution hexagonal hole collimator (1.5 mm hole diameter, 32 mm length, 4300 events/mCi/sec) at an imaging distance of 5 cm
Keywords :
biomedical electronics; biomedical equipment; cameras; p-i-n photodiodes; radioisotope imaging; 1.5 to 32 mm; 140 keV; 5 cm; 50 pA; 8 mus; Co; CsI(TI) crystals; CsI:Tl; Tc; breast cancer imaging; discrete scintillation camera module; medical diagnostic imaging; nuclear medicine; photodiodes; shaping time; silicon photodiode readout; Cameras; Energy resolution; Image resolution; Photodiodes; Photonic crystals; Photonic integrated circuits; Prototypes; Signal processing; Silicon; Spatial resolution;
fLanguage :
English
Journal_Title :
Nuclear Science, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9499
Type :
jour
DOI :
10.1109/23.681979
Filename :
681979
Link To Document :
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