@article{oai:repo.qst.go.jp:00044562,
 author = {Yamaya, Taiga and Hagiwara, Naoki and Obi, Takashi and Tsuda, Tomoaki and Kitamura, Keishi and Hasegawa, Tomoyuki and Haneishi, Hideaki and Inadama, Naoko and Yoshida, Eiji and Murayama, Hideo and 山谷 泰賀 and 萩原 直樹 and 小尾 高史 and 津田 倫明 and 北村 圭司 and 長谷川 智之 and 羽石 秀昭 and 稲玉 直子 and 吉田 英治 and 村山 秀雄},
 issue = {3},
 journal = {IEEE Transactions on Nuclear Science},
 month = {Jun},
 note = {We are developing a high-performance brain PET scanner, jPET-D4, which provides 4-layer depth-of-interaction(DOI) information. The scanner is designed to achieve not only high spatial resolution but also high scanner sensitivity with the DOI information obtained from multi-layered thin crystals. The scanner has 5 rings of 24 detector blocks each, and each block consists of 1024 GSO crystals of 2.9mm×2.9mm×7.5mm, which are arranged in 4 layers of 16×16 arrays. At this stage, a pair of detector blocks and a coincidence circuit have been assembled into an experimental prototype gantry. In this paper, as a preliminary experiment, we investigated the performance of the jPET-D4'spatial resolution using the prototype system. First, spatial resolution was measures from a filtered backprojection reconstructed image.To avoid systematic error and reduce computational cost in image reconstruction, we applied the DOI compression (DOIC) method followed by maximum likelihood expectation maximization that we had previously proposed. Trade-off characteristics between background noise and resolution were investigated because improved spatial resolution is possible only when enhanced noise is avoided. Experimental results showed that the jPET-D4 achieves better than 3mm spatial resolution over the field-of-view.},
 pages = {1123--1128},
 title = {Preliminary Resolution Performance of the Prototype System for a 4-Layer DOI-PET Scanner: jPET-D4},
 volume = {53},
 year = {2006}
}