A. Kishimoto, J. Kataoka, T. Kato, T. Miura, T. Nakamori, K. Kamada, S. Nakamura, Kenichi Sato, Y. Ishikawa, K. Yamamura, S. Yamamoto
{"title":"Development of a MPPC-based DOI-PET module with submillimeter 3-D resolution","authors":"A. Kishimoto, J. Kataoka, T. Kato, T. Miura, T. Nakamori, K. Kamada, S. Nakamura, Kenichi Sato, Y. Ishikawa, K. Yamamura, S. Yamamoto","doi":"10.1109/NSSMIC.2012.6551714","DOIUrl":null,"url":null,"abstract":"We are proposing a novel design for a module with depth of interaction (DOI) capability for gamma rays by measuring the pulse-height ratio of double-sided Multi-Pixel Photon Counters (MPPCs) coupled at both ends of a scintillation crystal block. Thanks to newly developed monolithic MPPC arrays consisting of 4 × 4 channels with a three-side buttable package, the module is very thin and compact, thereby enabling less dead space between each module when arranged into a fully designed gantry. To demonstrate our concept of a DOI measuring technique, we first made a 1-D crystal array consisting of five Ce-doped Gd<sub>3</sub>Al<sub>2</sub>Ga<sub>3</sub>O<sub>12</sub> (Ce:GAGG) cubic crystals measuring 3 × 3 × 3 mm<sup>3</sup> in size, separated by a layer of air. When the light signals output from both ends are read with the MPPCs, the position of each crystal is clearly distinguished with a spatial uncertainty of 0.48 ± 0.03 mm. For 3-D measurements, we then fabricated three different type arrays: [A] 4 × 4 × 4 matrix of 3 × 3 × 3 mm<sup>3</sup> pixels, [B] 5 × 5 × 5 matrix of 2 × 2 × 2 mm<sup>3</sup> pixels, and [C] 10 × 10 × 10 matrix of 1 × 1 × 1 mm<sup>3</sup> pixels, with each pixel divided by a BaSO<sub>4</sub> reflector in the 2-D direction and by a layer of air in the DOI direction. We demonstrated that the 3-D position of each Ce:GAGG pixel was clearly distinguished when illuminated by 662 keV gamma rays uniformly. Average energy resolutions of 9.8 ± 0.8 %,9.8 ± 0.9 %, and 13.2 ± 1.7 % were obtained for types A, B and C, respectively. These results suggest that our proposed method is simple and offers promise in achieving 1 mm 3-D spatial resolution for future medical imaging, partic","PeriodicalId":187728,"journal":{"name":"2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/NSSMIC.2012.6551714","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 3
Abstract
We are proposing a novel design for a module with depth of interaction (DOI) capability for gamma rays by measuring the pulse-height ratio of double-sided Multi-Pixel Photon Counters (MPPCs) coupled at both ends of a scintillation crystal block. Thanks to newly developed monolithic MPPC arrays consisting of 4 × 4 channels with a three-side buttable package, the module is very thin and compact, thereby enabling less dead space between each module when arranged into a fully designed gantry. To demonstrate our concept of a DOI measuring technique, we first made a 1-D crystal array consisting of five Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) cubic crystals measuring 3 × 3 × 3 mm3 in size, separated by a layer of air. When the light signals output from both ends are read with the MPPCs, the position of each crystal is clearly distinguished with a spatial uncertainty of 0.48 ± 0.03 mm. For 3-D measurements, we then fabricated three different type arrays: [A] 4 × 4 × 4 matrix of 3 × 3 × 3 mm3 pixels, [B] 5 × 5 × 5 matrix of 2 × 2 × 2 mm3 pixels, and [C] 10 × 10 × 10 matrix of 1 × 1 × 1 mm3 pixels, with each pixel divided by a BaSO4 reflector in the 2-D direction and by a layer of air in the DOI direction. We demonstrated that the 3-D position of each Ce:GAGG pixel was clearly distinguished when illuminated by 662 keV gamma rays uniformly. Average energy resolutions of 9.8 ± 0.8 %,9.8 ± 0.9 %, and 13.2 ± 1.7 % were obtained for types A, B and C, respectively. These results suggest that our proposed method is simple and offers promise in achieving 1 mm 3-D spatial resolution for future medical imaging, partic