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arXiv · 1801.03225

Study of a Prototype VP-PET Imaging System Based on highly Pixelated CdZnTe Detectors

Zheng-Qian Ye·Ying-Guo Li·Tian-Quan Wang·Ya-Ming Fan·Yong-Zhi Yin·Xi-Meng Chen
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Abstract

We are investigating a prototype virtual pinhole positron emission tomography (VP-PET) system for small animal imaging applications. The PET detector modules were made up of 1.3 mm lutetium-yttrium oxyorthosilicate (LYSO) arrays, and the insert detectors consists of 0.6 mm pixelated Cadmium Zinc Telluride (CdZnTe). To validate the imaging experiment, we conducted a Monte Carlo simulation for the VP-PET system in Geant4 Application for Emission Tomography (GATE). For a point source of Na-22 with 0.5 mm diameter, the filtered back-projection (FBP) algorithm reconstructed PET image shows a resolution of 0.7 mm full-width-at-half-maximum (FWHM). The system sensitivity is 0.46 cps/kBq at the center of field view (CFOV) of the PET system with a source activity of 0.925 MBq and an energy resolution of 350-650 keV. A rod source phantom and a Derenzo phantom with F-18 were also simulated to investigate the PET imaging capability. GATE simulation indicated that two point sources with 0.5 mm diameter 2 mm apart could be clearly separated using 0.6 mm pixelated CdZnTe detectors as insert devices in a VP-PET system.

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Zheng-Qian Ye, Ying-Guo Li, Tian-Quan Wang, Ya-Ming Fan, Yong-Zhi Yin, Xi-Meng Chen. 2018-01-10. Study of a Prototype VP-PET Imaging System Based on highly Pixelated CdZnTe Detectors. https://arxiv.org/abs/1801.03225

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