Technical Note: Performance evaluation of a small‐animal PET/CT system based on NEMA NU 4–2008 standards
- 12 July 2021
- journal article
- research article
- Published by Wiley in Medical Physics
- Vol. 48 (9), 5272-5282
- https://doi.org/10.1002/mp.15088
Abstract
Purpose The MetisTM PET/CT is a self-developed, silicon photomultiplier (SiPM) detector-based, rodent PET/CT system. The objective of this study was to evaluate the performance of the system using the National Electrical Manufacturers Association (NEMA) NU 4–2008 standard protocol. Methods Energy resolution, spatial resolution, sensitivity, scatter fraction (SF), noise-equivalent count rate (NECR), and image quality (IQ) characteristics were measured. A micro Derenzo phantom experiment was performed to evaluate the spatial resolution using three-dimensional ordered-subsets expectation maximization (3D-OSEM) and maximum likelihood expectation maximization (MLEM) reconstructed images. In addition, the CT imaging agent Ioverol 350 was mixed with fluorine-18 (18F)-fluorodeoxyglucose (FDG) and then injected into the micro Derenzo phantom to evaluate the PET/CT imaging. In vivo PET/CT imaging studies were also conducted in a healthy mouse and rat using 18F-FDG. Results The mean energy resolution of the system was 15.3%. The tangential resolution was 0.82 mm full-width half-maximum (FWHM) at the center of the field of the view (FOV), and the radial and axial resolution were generally lower than 2.0 mm FWHM. The spatial resolution was significantly improved when using 3D-OSEM, especially the axial FWHM could be improved by up to about 57%. The system absolute sensitivity was 7.7% and 6.8% for an energy window of 200–750 and 350–750 keV respectively. The scatter fraction was 8.2% and 12.1% for the mouse- and rat-like phantom respectively. The peak NECR was 1343.72 kcps at 69 MBq and 640.32 kcps at 53 MBq for the mouse- and rat-like phantom respectively. The 1-mm fillable rod in the IQ phantom can be clearly observed. We can identify the 0.6-mm aperture of the micro Derenzo phantom image clearly using 3D-OSEM (10 subsets, 5 iterations). We also performed the fusion of the PET and CT images of the mouse and the brain imaging of the rat. Conclusions The results show that the system has the characteristics of high-resolution, high-sensitivity, and excellent IQ and is suitable for rodent imaging-based research.Keywords
This publication has 36 references indexed in Scilit:
- National Electrical Manufacturers Association NU-4 Performance Evaluation of the PET Component of the NanoPET/CT Preclinical PET/CT ScannerJournal of Nuclear Medicine, 2011
- Performance Evaluation of the FLEX Triumph X-PET Scanner Using the National Electrical Manufacturers Association NU-4 StandardsJournal of Nuclear Medicine, 2010
- Design and performance evaluation of a coplanar multimodality scanner for rodent imagingPhysics in Medicine & Biology, 2009
- A novel, SiPM-array-based, monolithic scintillator detector for PETPhysics in Medicine & Biology, 2009
- Performance Evaluation of the Inveon Dedicated PET Preclinical Tomograph Based on the NEMA NU-4 StandardsJournal of Nuclear Medicine, 2009
- Latest Advances in Molecular Imaging InstrumentationJournal of Nuclear Medicine, 2008
- Recommendations on the Use of 18F-FDG PET in OncologyJournal of Nuclear Medicine, 2008
- Design evaluation of A-PET: A high sensitivity animal PET cameraIEEE Transactions on Nuclear Science, 2003
- Performance evaluation of the microPET P4: a PET system dedicated to animal imagingPhysics in Medicine & Biology, 2001
- Exact and approximate rebinning algorithms for 3-D PET dataIEEE Transactions on Medical Imaging, 1997