TITLE
2D Imaging Simulations of a Small Animal PET Scanner with DOI Measurement: jPET-RD
AUTHORS
Taiga Yamaya, Keishi Kitamura, Naoki Hagiwara, Takashi Obi, Tomoyuki Hasegawa, Eiji Yoshida, Tomoaki Tsuda , Naoko Inadama, Yasuhiro Wada, and Hideo Murayama
SOURCE
JAPANESE JOURNAL OF MEDICAL PHYSICS 25 (1): 13-23, MAR 2005
(PMID: 15961924 )

JJMP

ABSTRACT
We present a preliminary study on the design of a high sensitivity small animal DOT-PET scanner: jPET-RD (for Rodents with DOI detectors), which will contribute to molecular imaging. The 4-layer DOT block detector for the jPET-RD that consists of scintillation crystals (1.4mm x 1.4mm x 4.5mm) and a flat panel position-sensitive photomultiplier tube (52mm x 52mm) was previously proposed. In this paper, we investigate imaging performance of the jPET-RD through numerical simulations. The scanner has a hexagonal geometry with a small diameter and a large axial aperture. Therefore DOI information is expected to improve resolution uniformity in the whole field of view (FOV). We simulate the scanner for various parameters of the number of DOI channels and the crystal length. Simulated data are reconstructed using the maximum likelihood expectation maximization with accurate system modeling. The trade-off results between background noise and spatial resolution show that only shortening the length of crystal does not improve the trade-off at all, and that 4-layer DOT information improves uniformity of spatial resolution in the whole FOV. Excellent performance of the jPET-RD can be expected based on the numerical simulation results.

Fig.11

Fig. 11. Reconstructed images for the demonstration phantom at the same background noise level (NSD=0.09). Upper images are the enlarged one of the bottom images respectively.
KEYWORDS
positron emission tomography (PET); nuclear medicine; small animal PET; depth-of interaction (DOI); image reconstruction,