Performance evaluation of a staggered three-layer DOI PET detector using a 1 mm LYSO pitch with PETsys TOFPET2 ASIC: comparison of HAMAMATSU and KETEK SiPMs

Binder, Tim; Kang, Han Gyu; Nitta, Munetaka; Schneider, Florian; Yamaya, Taiga; Parodi, Katia; Wiest, Florian und Thirolf, Peter G. (2021): Performance evaluation of a staggered three-layer DOI PET detector using a 1 mm LYSO pitch with PETsys TOFPET2 ASIC: comparison of HAMAMATSU and KETEK SiPMs. In: Physics in Medicine and Biology, Bd. 66, Nr. 12, 125016

Abstract

In this study, we propose a staggered three-layer depth-of-interaction (DOI) detector with a 1 mm crystal pitch and 19.8 mm total crystal thickness for a high-resolution and high-sensitivity small animal in-beam PET scanner. A three-layered stacked LYSO scintillation array (0.9 x 0.9 x 6.6 mm(3) crystals, 23 x 22 mm(2) surface area) read out by a SiPM array (8 x 8 channels, 3 x 3 mm(2) active area/channel and 50 mu m microcell size) with data acquisition, signal processing and digitization performed using the PETsys Electronics Evaluations kit (based on the TOFPET v2c ASIC) builds a DOI LYSO detector block. The performance of the DOI detector was evaluated in terms of crystal resolvability, energy resolution, and coincidence resolving time (CRT). A comparative performance evaluation of the staggered three-layer LYSO block was conducted with two different SiPM arrays from KETEK and HAMAMATSU. 100% (KETEK) and 99.8% (HAMAMATSU) of the crystals were identified, by using a flood irradiation the front- and back-side. The average energy resolutions for the 1st, 2nd, and 3rd layers were 16.5 (+/- 2.3)%, 20.9(+/- 4.0)%, and 32.7 (+/- 21.0)% (KETEK) and 19.3 (+/- 3.5)%, 21.2 (+/- 4.1)%, and 26.6 (+/- 10.3)% (HAMAMATSU) for the used SiPM arrays. The measured CRTs (FWHM) for the 1st, 2nd, and 3rd layers were 532 (+/- 111) ps, 463 (+/- 108) ps, and 447 (+/- 111) ps (KETEK) and 402 (+/- 46) ps, 392 (+/- 54) ps, and 408 (+/- 196) ps (HAMAMATSU). In conclusion, the performance of the staggered three-layer DOI detector with 1 mm LYSO pitch and 19.8 mm total crystal thickness was fully characterized. The feasibility of a highly performing readout of a high resolution DOI PET detector via SiPM arrays from KETEK and HAMAMATSU employing the PETsys TOFPET v2c ASIC could be demonstrated.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 0031-9155
• Sprache: Englisch