2017 AAPM Annual Meeting
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Session Title: Emerging and New Generation PET: Instrumentation, Technology, Characteristics and Clinical Practice
Question 1: All of the following degrading factors can have routinely-applied correction algorithms. Some can be reduced in the PET design. Which degrading factor cannot be circumvented with PET design?
Reference:Cherry SR, Sorenson JA, Phelps ME. Physics in Nuclear Medicine (4th edition). 2012. Saunders Elsevier
Choice A:Attenuation.
Choice B:Scattered background.
Choice C:Randoms background.
Choice D:Dead Time.
Question 2: Why are there no TOF PET systems with bismuth germanate detectors?
Reference:Cherry SR, Sorenson JA, Phelps ME. Physics in Nuclear Medicine (4th edition). 2012. Saunders Elsevier
Choice A:It would be too expensive.
Choice B:Bismuth germanate is no longer available.
Choice C:The effective atomic number is too high.
Choice D:The scintillation light cannot be measured with sufficient timing resolution.
Question 3: Can TOF images be noisier than non-TOF images?
Reference:Cherry SR, Sorenson JA, Phelps ME. Physics in Nuclear Medicine (4th edition). 2012. Saunders Elsevier
Choice A:No. TOF images are always better than non-TOF images.
Choice B:Yes. TOF images are always noisier than non-TOF images.
Choice C:Yes. TOF only pertains to image resolution, and doesn't affect noise.
Choice D:Yes. It depends on the reconstruction parameters used for the TOF and non-TOF images.
Question 4: Compared to conventional photo-multiplier PET systems, spatial resolution of the SiPM digital photon counting PET system is NOT affected by:
Reference:WW Moses. Fundamental Limits of Spatial Resolution in PET. Nucl Instrum Methods Phys Res A. 2011 Aug 21; 648 Supplement 1: S236–S240 Jun Zhang, Michael V Knopp etc. Effect of next generation SiPM digital photon counting PET technology on effective system spatial resolution. SNMMI 2017 June 13; Denver, USA
Choice A:Crystal size.
Choice B:Positron Range.
Choice C:Noncollinearity / Acollinearity.
Choice D:Localization decoding.
Question 5: For a 48cm diameter object, an estimated sensitivity gain and the SNR improvement of the digital photon counting TOF PET (320ps, 4.8cm uncertainty) compared to nonTOF PET are about :
Reference:Karp JS. Surti S, Daube-Witherspoon ME and Muehllehner G. Advances in Time-Of-Flight PET. Phys Med, 32(1): 12-22. Budinger TF. Time-of-Flight Positron Emission Tomography - Status Relative to Conventional PET. J Nucl Med. 1983;24(1):73–76.
Choice A:5.0 and 5.0
Choice B:10.0 and 10.0
Choice C:10.0 and 3.2
Choice D:10.0 and 5.0
Question 6: The timing resolution on the digital PET/CT scanners from GE is in the range of:
Reference:Grant AM, Deller TW, Khalighi MM, Maramraju SH, Delso G, Levin CS. NEMA NU 2-2012 performance studies for the SiPM-based ToF-PET component of the GE SIGNA PET/MR system. Med Phys. 2016 May;43(5):2334.
Choice A:250-350 ps.
Choice B:350-450 ps.
Choice C:450-550 ps.
Choice D:Depends on the number of block rings.
Question 7: The sensitivity of GE PET/CT scanners with the same number of detector rings:
Reference:Reynés-Llompart G, Gámez-Cenzano C, Romero-Zayas I, Rodríguez-Bel L, Vercher-Conejero JL, Martí-Climent JM. Performance Characteristics of the Whole-Body Discovery IQ PET/CT System. J Nucl Med. 2017 Jul;58(7):1155-1161. Grant AM, Deller TW, Khalighi MM, Maramraju SH, Delso G, Levin CS. NEMA NU 2-2012 performance studies for the SiPM-based ToF-PET component of the GE SIGNA PET/MR system. Med Phys. 2016 May;43(5):2334.
Choice A:Is higher for digital compared to conventional detectors systems.
Choice B:Is lower for digital compared to conventional detector systems.
Choice C:Is about the same for digital compared to conventional detector systems..
Choice D:Is independent of the detector system.
Question 8: Why is LSO or LYSO commonly used as a detector material in PET/CT scanners, rather than NaI(Tl), as commonly used in SPECT?
Reference:Vandenberghe et al. Time-of-flight PET: a review of different benefits and recent developments in time-of-flight PET. Euro J Nucl Med, 3: Dec 2015.
Choice A:The energy resolution is better at 511 keV to improve scatter rejection.
Choice B:The timing resolution is better and enables TOF imaging.
Choice C:The detector can be used for both PET as well as CT, thereby enabling PET/CT scanners.
Choice D:It is less a less expensive scintillation material.
Question 9: Which of the following are advantages of silicon photo-multipliers compared to conventional photo-multipliers?
Reference:Surti S, Karp JS. Advances in Time-Of-Flight PET. Phys Med, 32(1): 12-22, Jan 2016.
Choice A:They can be incorporated into PET/MR scanners.
Choice B:They can be used in TOF PET/CT scanners.
Choice C:They are significantly less expensive.
Choice D:All of the above.
Question 10: Improved time-of-flight resolution leads to which of the following?
Reference:Surti S. Update on Time-of-Flight PET Imaging. J Nucl Med, 56(1): 98-105, Jan 2015.
Choice A:Improved spatial resolution.
Choice B:Increased scan counts.
Choice C:Improved image signal-to-noise.
Choice D:All of the above.
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