@article{oai:repo.qst.go.jp:00046287,
 author = {Tashima, Hideaki and Yoshida, Eiji and Kinouchi, Shoko and Nishikido, Fumihiko and Inadama, Naoko and Murayama, Hideo and Suga, Mikio and Haneishi, Hideaki and Yamaya, Taiga and 田島 英朗 and 吉田 英治 and 木内 尚子 and 錦戸 文彦 and 稲玉 直子 and 村山 秀雄 and 菅 幹生 and 羽石 秀昭 and 山谷 泰賀},
 issue = {1},
 journal = {IEEE Transactions on Nuclear Science},
 month = {Feb},
 note = {The OpenPET and its real-time imaging capability have great potential for real-time tumor tracking in medical procedures such as biopsy and radiation therapy. For the real-time imaging system, we intend to use the one-pass list-mode dynamic row-action maximum likelihood algorithm (DRAMA) and implement it using general-purpose computing on graphics processing units (GPGPU) techniques. However, it is difficult to make consistent reconstructions in real-time because the amount of list-mode data acquired in PET scans may be large depending on the level of radioactivity, and the reconstruction speed depends on the amount of the list-mode data. In this study, we developed a system to control the data used in the reconstruction step while retaining quantitative performance. In the proposed system, the data transfer control system limits the event counts to be used in the reconstruction step according to the reconstruction speed, and the reconstructed images are properly intensified by using the ratio of the used counts to the total counts. We implemented the system on a small OpenPET prototype system and evaluated the performance in terms of the real-time tracking ability by displaying reconstructed images in which the intensity was compensated. The intensity of the displayed images correlated properly with the original count rate and a frame rate of 2 frames per second was achieved with average delay time of 2.1 s.},
 pages = {40--46},
 title = {Real-Time Imaging System for the OpenPET},
 volume = {59},
 year = {2012}
}