title: Development of a small single-ring OpenPET prototype with a novel transformable architecture.
abstract: 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 (11)C 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.
authors: Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
authors: Hideaki
authors: H
authors: Tashima
authors: Eiji
authors: E
authors: Yoshida
authors: Naoko
authors: N
authors: Inadama
authors: Fumihiko
authors: F
authors: Nishikido
authors: Yasunori
authors: Y
authors: Nakajima
authors: Hidekatsu
authors: H
authors: Wakizaka
authors: Tetsuya
authors: T
authors: Shinaji
authors: Munetaka
authors: M
authors: Nitta
authors: Shoko
authors: S
authors: Kinouchi
authors: Mikio
authors: M
authors: Suga
authors: Hideaki
authors: H
authors: Haneishi
authors: Taku
authors: T
authors: Inaniwa
authors: Taiga
authors: T
authors: Yamaya
mesh_terms: D002250:Carbon Radioisotopes; D004867:Equipment Design; D049268:Positron-Emission Tomography / Q000295:instrumentation*
chemical_list: D002250:Carbon Radioisotopes