@misc{oai:repo.qst.go.jp:00077145,
 author = {Kang, Hangyu and Nishikido, Fumihiko and Tashima, Hideaki and Sakai, Toshiaki and Yamaya, Taiga and Kang, Hangyu and Nishikido, Fumihiko and Tashima, Hideaki and Yamaya, Taiga},
 month = {Oct},
 note = {A small animal depth-of-interaction (DOI) positron emission tomography (PET) detector based on a trapezoid shaped crystal was originally proposed by Simon Cherry’s group at UC Davis as a way to minimize the gaps between detector blocks. However, manufacturing the trapezoid shaped crystal is costly due to the complex geometry. As a more practical idea, here we developed a small animal DOI PET detector using a sub-surface laser engraving (SSLE) based trapezoid geometry. The imaging performance of the proposed PET scanner was presented in the most recent GATE User’s workshop. In the developed detector, we pixelized a 20 mm long monolithic trapezoid LYSO plate (top =  15.3 mm, bottom = 25.6 mm, thickness = 0.9 mm) into a 15 × 1 array by using SSLE to yield a top crystal pitch of 1.02 mm and a bottom crystal pitch of 1.71 mm. The 11 SSLE processed LYSO crystal plates were assembled together to make a 15 × 11 array. The LYSO plates were optically isolated by using as enhanced specular reflector (ESR). A 7×6 array SiPM (S13360-2050VE, Hamamatsu Photonics, Japan) with a pixel pitch of 2.4 mm and an 8×4 array SiPM (S13361-3050NE-04 Hamamatsu Photonics) with a pixel pitch of 3.2 mm were coupled to the top and bottom surfaces of the trapezoid LYSO array, respectively. For an optical coupling, room temperature vulcanized (RTV) light guides with a thickness of 1 mm were inserted between the LYSO and SiPM array. The SiPM output signals were multiplexed by using a resistive network, and then digitized by CAMAC DAQ. We could identify all the crystals in the 2D flood map. The measured DOI resolution and energy resolution were 2.3±0.6 mm and 11.6±0.7%, respectively. In the future, we want to develop a prototype trapezoid geometry small animal DOI PET scanner for high-resolution and high-sensitivity mouse brain imaging., 2019 IEEE Nuclear Science Symposium and Medical Imaging Conference},
 title = {Initial Results for a Small Animal DOI PET Detector with Sub-Surface Laser Engraving Based Trapezoid Geometry},
 year = {2019}
}