Title :
Verification of concepts for DOI determination in a three-layer small animal PET
Author :
Kwon, Sun Il ; Lee, Jae Sung ; Ito, Mikiko ; Sim, Kwang-Souk ; Lee, Geon Song ; Park, Kwang Suk ; Rhee, June Tak ; Hong, Seong Jong
Author_Institution :
Seoul Nat. Univ., Seoul
fDate :
Oct. 26 2007-Nov. 3 2007
Abstract :
Improved spatial resolution without sacrificing sensitivity is one of the most challenging development goals for small animal PET scanners. The 3-layer configuration that we proposed utilizes relative offsets of half a crystal pitch in x- and y-directions, and pulse shape discrimination to obtain depth of interaction (DOI). Three layers of crystals with a dimension 1.5times1.5times7.0 mm3 were composed of a L0.2GSO (Lu0.4Gd1.6SiO4:Ce) crystal layer and a L0.9GSO (Lu1.6Gd0.4SiO4) crystal layer aligned with each other, and a L0.9GSO crystal layer offset of at half a crystal pitch in x- and y-directions. The L0.2GSO crystal layer was attached to a Hamamatsu H9500 flat-panel PMT. The devised small animal PET scanner has a diameter of 84 mm with one detector ring, and can be upgraded to two detector rings. GEANT4 Monte-Carlo simulation was used to estimate sensitivities of ~12 % and ~20%, respectively, at the center of one and two PMT ring system. We present flood images with peak-to-valley ratios of about 5~6 obtained using 22Na and layer identification capability of ~95% with pulse shape analysis using a 100 mega-sample per second (MSPS) analog-to-digital converter (ADC), and verified the basic concepts of the multi-layer small animal PET.
Keywords :
Monte Carlo methods; analogue-digital conversion; cerium; gadolinium compounds; image resolution; image scanners; lutetium compounds; positron emission tomography; ADC; DOI determination; GEANT4 Monte-Carlo simulation; Hamamatsu H9500 flat-panel PMT; Lu0.4Gd1.6SiO4:Ce; analog-to-digital converter; depth-of-interaction; pulse shape analysis; pulse shape discrimination; small animal PET scanners; spatial resolution; three-layer small animal PET; Analog-digital conversion; Animals; Crystals; Detectors; Floods; Image analysis; Positron emission tomography; Pulse shaping methods; Shape; Spatial resolution; Animal PET; Cerium Doped lutetium Gadolinium Oxyorthosilicate (LGSO); Depth of Interaction (DOI); Three-layer Crystal;
Conference_Titel :
Nuclear Science Symposium Conference Record, 2007. NSS '07. IEEE
Conference_Location :
Honolulu, HI
Print_ISBN :
978-1-4244-0922-8
Electronic_ISBN :
1095-7863
DOI :
10.1109/NSSMIC.2007.4436745