Speaker
Mikiko Ito
(Institute of Particle Physics and Astrophysics, ETH Zurich, Zurich, Switzerland)
Description
Two different depth-of-interaction (DOI) encoding detector designs were studied for the SAFIR (Small Animal Fast Insert for mRi) PET system to improve spatial resolution in the axial direction. One is a two-layer DOI detector with two layers of crystals stacked with an offset of half crystal pitch. The other is a single-layer DOI detector using triangular shaped ESR reflectors between crystals. Both detectors utilized the same size of crystal cross-section (2.1 mm × 2.1 mm), total length of the crystal block (12 mm), and are mounted on a 4 × 4 SiPM array with 2 mm × 2 mm pixels. In this study, we report the detector performances of the two DOI-encoding designs as compared with a non-DOI detector composed of the same dimensions of crystals and SiPMs with one-to-one coupling. Energy resolutions were calculated after SiPM non-linearity correction and evaluated to be 10.6% for the non-DOI detector, 12.3% for the two-layer DOI detector, and 10.2% for the single-layer DOI detector. Coincidence resolving time resolutions at FWHM were calculated to be 336.8 ps for the non-DOI detector, 406.5 ps and 382.0 ps for the top and bottom layers of the two-layer DOI detector, and 295.6 ps for the single-layer DOI detector. The two-layer DOI detector exhibits a degradation of timing performance while the single-layer DOI detector shows excellent timing performance. For a DOI performance, the two-layer DOI detector provided a clear discrimination of events occurred in the top or bottom layer from a crystal map with a peak-to-valley of 9:1. The single-layer DOI detector provided a DOI resolution of ~ 3.1 mm FWHM, but a careful calibration is necessary for the DOI estimation.
Primary author
Mikiko Ito
(Institute of Particle Physics and Astrophysics, ETH Zurich, Zurich, Switzerland)
Co-authors
Ms
Afroditi Eleftheriou
(Institute for Pharmacology and Toxicology, University of Zürich, Switzerland)
Ms
Agnieszka Zagozdzinska-Bochenek
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Prof.
Alfred Buck
(Clinic of Nuclear Medicine, University of Zürich, Switzerland)
Prof.
Bruno Weber
(Institute for Pharmacology and Toxicology, University of Zürich, Switzerland)
Dr
Charalampos Tsoumpas
(Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, United Kingdom)
Mr
Christian Ritzer
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Mr
Diogo Di Calafiori
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Dr
Geoffrey Warnock
(Institute for Pharmacology and Toxicology, University of Zürich, Switzerland)
Prof.
Günther Dissertori
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Dr
Ilaria Sacco
(Institute of Computer Engineering, University Heidelberg, Germany)
Dr
Jannis Fischer
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Mr
Jisoo Kim
(Department of Nuclear and Quantum Engineering, KAIST, South Korea)
Dr
Josep F. Oliver
(Instituto de Fisica Corpuscular (CSIC-UV), Universitat de València, Spain)
Mr
Lubomir Djambazov
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Prof.
Markus Rudin
(Institute for Biomedical Engineering, ETH Zürich, Switzerland)
Dr
Matthias Wyss
(Institute for Pharmacology and Toxicology, University of Zürich, Switzerland)
Dr
Michael Ritzert
(Institute of Computer Engineering, University Heidelberg, Germany)
Dr
Paola Solevi
(Institute of Medical Technology, Otto-von-Guericke University Magdeburg, Germany)
Ms
Parisa Khateri
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Prof.
Peter Fischer
(Institute of Computer Engineering, University Heidelberg, Germany)
Mr
Robert Becker
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Mr
Ulf Röser
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Dr
Volker Commichau
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
Dr
Werner Lustermann
(Institute for Particle Physics and Astrophysics, ETH Zürich, Switzerland)
