title: A compact high resolution flat panel PET detector based on the new 4-side buttable MPPC for biomedical applications.
abstract: Compact high-resolution panel detectors using virtual pinhole (VP) PET geometry can be inserted into existing clinical or pre-clinical PET systems to improve regional spatial resolution and sensitivity. Here we describe a compact panel PET detector built using the new Though Silicon Via (TSV) multi-pixel photon counters (MPPC) detector. This insert provides high spatial resolution and good timing performance for multiple bio-medical applications. Because the TSV MPPC design eliminates wire bonding and has a package dimension which is very close to the MPPC's active area, it is 4-side buttable. The custom designed MPPC array (based on Hamamatsu S12641-PA-50(x)) used in the prototype is composed of 4 × 4 TSV-MPPC cells with a 4.46 mm pitch in both directions. The detector module has 16 × 16 lutetium yttrium oxyorthosilicate (LYSO) crystal array, with each crystal measuring 0.92 × 0.92 × 3 mm3with 1.0 mm pitch. The outer diameter of the detector block is 16.8 × 16.8 mm2. Thirty-two such blocks will be arranged in a 4 × 8 array with 1 mm gaps to form a panel detector with detection area around 7 cm × 14 cm in the full-size detector. The flood histogram acquired with Ge-68 source showed excellent crystal separation capability with all 256 crystals clearly resolved. The detector module's mean, standard deviation, minimum (best) and maximum (worst) energy resolution were 10.19%, +/-0.68%, 8.36% and 13.45% FWHM, respectively. The measured coincidence time resolution between the block detector and a fast reference detector (around 200 ps single photon timing resolution) was 0.95 ns. When tested with Siemens Cardinal electronics the performance of the detector blocks remain consistent. These results demonstrate that the TSV-MPPC is a promising photon sensor for use in a flat panel PET insert composed of many high resolution compact detector modules.
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Wen
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Bosky
authors.initials: B
authors.lastname: Ravindranath
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: O'Sullivan
authors.affiliation: Saint Louis University, St. Louis, MO 63103, USA.
authors.forename: David
authors.initials: D
authors.lastname: Catherall
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Shouyi
authors.initials: S
authors.lastname: Wei
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Sergey
authors.initials: S
authors.lastname: Komarov
authors.affiliation: Washington University in St Louis, MO 63110, USA.
authors.forename: Yuan-Chuan
authors.initials: YC
authors.lastname: Tai
keywords: 4-side buttable MPPC; PET detector; flat panel; high resolution