Preprint / Version 2

Performance evaluation of S-PET, a compact, high sensitivity and high resolution small animal PET prototype

This article is a preprint and has not been certified by peer review.

Authors

    Hang Yang,  
    Hang Yang
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    • School of Astronautics, Harbin Institute of Technology, Harbin, China
    Wen He,  
    Wen He
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    • Department of Radiology, Stanford University, Stanford, CA, USA
    Xin Zhao,  
    Xin Zhao
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    • Institute of Medical Technology, Peking University Health Science Center, Peking University, Beijing, China
    Guangming Li,  
    Guangming Li
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    • School of Sciences, Beijing University of Posts and Telecommunications, Beijing, China
    Yangyang Zhao,  
    Yangyang Zhao
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    • University of Science and Technology Beijing, Beijing Engineering Research Center of Industrial Spectrum Imaging, School of Automation and Electrical Engineering, Beijing, China
    Wenjie Huang,   Yong Huang,   Ming Niu,  
    Ming Niu
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
    Ying Liang,   Zheng Gu
    Zheng Gu
    • Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
Categories
Bioengineering & Biotechnology
Keywords
small animal imaging; PET; performance evaluation; instrumentation; molecular imaging; depth-of-interaction

Abstract

S-PET is a compact, high sensitivity and high resolution small animal PET prototype developed at Shenzhen Bay Laboratory (SZBL). The S-PET system employs a phoswich depth of interaction (DOI) detector design, which also allows identification of the large majority of the cross layer crystal scatter (CLCS) events. This work evaluates its performance characteristics following the National Electrical Manufacturers Association (NEMA) NU4-2008 protocol. The S-PET consists of twenty flat panel type detectors arranged in two rings. The inner diameter is 80 mm and the axial field of view (FOV) is 104.5 mm. Each detector is comprised of two layers of phoswich scintillator crystal arrays, an oblique edge cut glass lightguide and two multipixel photon counter (MPPC) arrays. The front (annihilation photon entrance) layer is a 30 × 60 pixelated cerium doped lutetium yttrium orthosilicate (LYSO) scintillator array with individual crystals measuring 0.79 × 0.79 × 5 mm3. The back (towards the MPPCs) layer is a 20 × 40 pixelated bismuth germanate (BGO) scintillator array with individual crystals measuring 1.22 × 1.22 × 7.5 mm3. For energy windows 350-650 keV, the peak absolute sensitivity at the center of the FOV was 14.9% including CLCSevents, and 11.9% excluding CLCS events. The average system energy resolution derived by averaging the individual crystal spectra was 11.2% ± 3.1% for LYSO and 28.3% ± 5.8% for BGO. The 3D ordered-subsets expectation maximization (OSEM) reconstructed image with spatially variant point spread function (PSF) modeling of a point source in air, ranged from 0.66 mm to 1.09 mm, with an average value of 0.78 ± 0.10 mm at all measured locations. The peak noise equivalent count rate (NECR) and scatter fractions were 237.4 kcps at 11.9 MBq and 13.0% for the mouse-sized phantom, and 110.3 kcps at 11.9 MBq and 23.3% for the rat-sized phantom. For the NEMA image quality phantom, the uniformity was 6.3%, and the spillover ratios measured in the water- and air-filled cold region chambers were 11.1% and 7.9%, respectively. The recovery coefficients (RC) ranged from 0.36 to 0.89. The comprehensive results demonstrate that S-PET developed at SZBL possesses high spatial resolution and high sensitivity, which meets the requirements of preclinical research, such as mouse and rat imaging.

Metrics

Favorites: 1
Views: 198
Downloads: 24

DOI:

https://doi.org/10.65215/LTSpreprints.2026.01.26.000101

Submission ID:

101

Downloads

Posted

2026-01-26

Versions

How to Cite

Yang, H., He, W., Zhao, X., Li, G., Zhao, Y., Huang, W., Huang, Y., Niu, M., Liang, Y., & Gu, Z. (2026). Performance evaluation of S-PET, a compact, high sensitivity and high resolution small animal PET prototype. LangTaoSha Preprint Server. https://doi.org/10.65215/LTSpreprints.2026.01.26.000101

Declaration of Competing Interests

The authors declare no competing interests to disclose.

Copyright

The copyright holder for this preprint is the author/funder.

All rights reserved. This work is protected by copyright. No part of this work may be reproduced, distributed, or transmitted in any form or by any means without the prior written permission of the copyright holder.