Abstract
Purpose
The new GE Discovery STE and Discovery VCT respectively combine 16-slice and 64-slice CT with PET. The PET scanner has a new BGO detector block of 8×6 matrix (6.3×4.7×30 mm3). The aim of this study was to test the performance of the new scanner.
Methods
The PET performance evaluation was done using NEMA methodology. Owing to improved front-end electronics, the system was tested with different energy window and coincidence timing settings.
Results
Transaxial resolution FWHM for 2D(3D) mode at 1 cm offset from the centre of the field of view (R1) was 4.87 mm (5.12 mm) and at 10 cm off centre (R10) radially 5.70 mm (5.89 mm) and tangentially 5.84 mm (5.47 mm). The axial resolutions were 4.4 mm (5.18 mm) (R1) and 5.99 mm (5.86 mm) (R10). The sensitivities were 2.3 cps/kBq (8.8 cps/kBq) (R0, centre of field of view) and 2.3 cps/kBq (8.9 cps/kBq) (R10). The system scatter fraction was 21.4% in 2D at an energy of 375 keV (33.9% in 3D mode at a higher energy of 425 keV). Peak noise equivalent count rates (k=1) were 84.9 kcps at 43.9 kBq/ml (2D) and 67.6 kcps at 12.1 kBq/ml (3D). In image quality measurement the hot sphere to background contrast with 10- to 22-mm diameter spheres varied from 14% to 68%, being slightly better in 3D than in 2D mode. Cold sphere contrast was 67% in 2D and 59% in 3D mode.
Conclusion
GE’s new STE and VCT PET/CT systems have improved spatial resolution without loss in sensitivity. When compared with the LYSO crystal-based GE Discovery RX, the resolution and scatter fraction are comparable, the count rate capability is lower but the sensitivity is higher.
Similar content being viewed by others
References
DeGrado TR, Turkington TG, Williams JJ, Stearns CW, Hoffman JM, Coleman RE. Performance characteristics of a whole-body PET scanner. J Nucl Med 1994;35:1398–406.
Brix G, Zaers J, Adam LE, Bellemann ME, Ostertag H, Trojan H, et al. Performance evaluation of a whole-body PET scanner using the NEMA protocol. J Nucl Med 1997;38:1614–23.
Erdi YE, Nehmeh SA, Mulnix T, Humm JL, Watson CC. PET performance measurements for an LSO-based combined PET/CT scanner using National Electrical Manufacturers Association NU 2-2001 standard. J Nucl Med 2004;45:813–21.
Brambilla M, Secco C, Dominietto M, Matheoud R, Sacchetti G, Inglese E. Performance characteristics obtained for a new 3-dimensional lutetium oxyorthosilicate-based whole-body PET/CT scanner with the National Electrical Manufacturers Association NU 2-2001 standard. J Nucl Med 2005;46:2083–91.
Kemp BJ, Kim C, Williams JJ, Ganin A, Lowe VJ. NEMA NU 2-2001 performance measurements of an LYSO-based PET/CT system in 2D and 3D acquisition modes. J Nucl Med 2006;47:1960–7.
Humm JL, Rosenfeld A, Del Guerra A. From PET detectors to PET scanners. Eur J Nucl Med Mol Imaging 2003;30:1574–97.
Karp JS. Is LSO the future of PET? Against. Eur J Nucl Med Mol Imaging 2002;29:1525–8.
Surti S, Kuhn A, Werner MW, Perkins AE, Kolthammer J, Karp JS. Performance of Philips Gemini TF PET/CT scanner with special consideration for its time-of-flight imaging capabilities. J Nuc Med 2007;48:471–80.
National Electrical Manufacturers Association. NEMA NU-2 Standards Publication NU-2-2001: performance measurements of positron emission tomography. Rosslyn, VA: National Electrical Manufacturers Association, 2001.
Daube-Witherspoon ME, Karp JS, Casey ME, DiFilippo FP, Hines H, Muehllehner G, et al. PET performance measurements using the NEMA NU 2-2001 standard. J Nucl Med 2002;43:1398–409.
National Electrical Manufacturers Association. NEMA NU-2 Standards Publication NU-2-1994: Performance measurements of positron emission tomography. Washington DC: National Electrical Manufacturers Association, 1994.
Karp JS, Daube-Witherspoon ME, Hoffman EJ, Lewellen TK, Links JM, Wong WH, et al. Performance standards in positron emission tomography. J Nucl Med 1991;32:2342–50.
Bettinardi V, Danna M, Savi A, Lecchi M, Castiglioni I, Gilardi MC, et al. Performance evaluation of the new whole-body PET/CT scanner: Discovery ST. Eur J Nucl Med Mol Imaging 2004;31:867–81.
Mawlawi O, Podoloff DA, Kohlmeyer S, Williams JJ, Stearns WS, Culp RF, et al. Performance characteristics of a newly developed PET/CT scanner using NEMA standards in 2D and 3D modes. J Nucl Med 2004;45:1734–42.
Bailey DL, Jones T, Spinks TJ. A method for measuring the absolute sensitivity of positron emission tomographic scanners. Eur J Nucl Med 1991;18:374–9.
Iatrou M, Ross SG, Manjeshwar RM, Stearns CW. A fully 3D iterative image reconstruction algorithm incorporating data corrections. Nuclear Science Symposium Conference Record, IEEEVolume 4, Issue 16–22 Oct 2004, pp 2493–7. DOI 10.1109/NSSMIC.2004.1462761.
Seppänen MP, Komar G, Kotoneva E, Teräs M, Minn H. Comparison of 2D and 3D VUE Point reconstruction of PET images with different acquisition times in oncological patients [abstract]. Eur J Nucl Med Mol Imaging 2006;33 Suppl 2:137.
Acknowledgements
We wish to thank all TPC GE staff involved in this project. We especially thank Helmut Bammer and Eira Kotoneva for helping to perform the phantom studies.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Teräs, M., Tolvanen, T., Johansson, J.J. et al. Performance of the new generation of whole-body PET/CT scanners: Discovery STE and Discovery VCT. Eur J Nucl Med Mol Imaging 34, 1683–1692 (2007). https://doi.org/10.1007/s00259-007-0493-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00259-007-0493-3