@article{oai:repo.qst.go.jp:00047399,
 author = {Tashima, Hideaki and Yoshida, Eiji and Inadama, Naoko and Nishikido, Fumihiko and Nakajima, Yasunori and Wakizaka, Hidekatsu and Shinaji, Tetsuya and Nitta, Munetaka and Kinouchi, Shoko and Suga, Mikio and Haneishi, Hideaki and Inaniwa, Taku and Yamaya, Taiga and 田島 英朗 and 吉田 英治 and 稲玉 直子 and 錦戸 文彦 and 中島 靖紀 and 脇坂 秀克 and 品地 哲弥 and 新田 宗孝 and 木内 尚子 and 菅 幹生 and 羽石 秀昭 and 稲庭 拓 and 山谷 泰賀},
 issue = {4},
 journal = {Physics in Medicine and Biology},
 month = {Feb},
 note = {The single-ring OpenPET (SROP), for which the detector arrangement has a cylinder shape cut by two parallel planes at a slant angle to form an open space, is our original proposal for in-beam PET. In this study, we developed a small prototype of an axial-shift type SROP (AS-SROP) with a novel transformable architecture for a proof-of-concept. In the AS-SROP, detectors originally forming a cylindrical PET are axially shifted little by little. We designed the small AS-SROP prototype for 4-layer depth-of-interaction detectors arranged in a ring diameter of 250 mm. The prototype had two modes: open and closed. The open mode formed the SROP with the open space of 139 mm and the closed mode formed a conventional cylindrical PET. The detectors were simultaneously moved by a rotation handle allowing them to be transformed between the two modes. We evaluated the basic performance of the developed prototype and carried out in-beam imaging tests in the HIMAC using 11C radioactive beam irradiation. As a result, we found the open mode enabled in-beam PET imaging at a slight cost of imaging performance; the spatial resolution and sensitivity were 2.6 mm and 5.1% for the open mode and 2.1 mm and 7.3% for the closed mode. We concluded that the AS-SROP can minimize the decrease of resolution and sensitivity, for example, by transforming into the closed mode immediately after the irradiation while maintaining the open space only for the in-beam PET measurement.},
 pages = {1795--1809},
 title = {Development of a small single-ring OpenPET prototype with a novel transformable architecture},
 volume = {61},
 year = {2016}
}