Abstract
Background: Increased throughput in small animal preclinical studies using positron emission tomography leads to reduced costs and improved efficiency of experimental design, however the presence of multiple off-centre subjects, as opposed to a single centered one, may affect image quality in several ways.Methods: We evaluated the count rate performance using a NEMA scatter phantom. A Monte Carlo simulation of the system was validated against this dataset and used to simulate the count rate performance for dual scatter phantoms. NEMA NU4 image quality phantoms were then scanned in the central and offset positions, as well as in the offset position next to a uniform activity phantom. Uniformity, recovery coefficients and spillover ratios were then compared, as were two time frames for acquisition.Results: Count rate performance assessed with a single NEMA scatter phantom was in line with previous literature, with simulated data in good agreement. Simulation of dual scatter phantoms showed an increase in scatter fraction. For the NEMA Image Quality phantom, uniformity and Recovery coefficients were degraded in the offset, and dual phantom cases, while spillover ratios were increased, notably when the chamber was placed nearest the gantry. Image quality metrics were comparable between the 20- and 10 min timeframes.Conclusion: Dual animal scanning results in some loss of image quality on the Sedecal Argus PET scanner; however, this degradation is within acceptable limits.
Highlights
Preclinical Positron Emission Tomography (PET) allows the longitudinal study of a range of biological processes in disease models, as well as being invaluable in the screening of novel diagnostic/theranostic PET probes
The simulated data, show that 57.9% of scattered events occur within the phantom, and 28.4% of events take place in the Delrin tube, which resides in the scanner bore to protect the detector rings and electronics. 30% of scattered events occur on the gantry shielding and less than 1% on the animal bed
It is not possible to assess the effect of scatter on image quality directly as this will depend on the implemented corrections, FIGURE 5 | Assessment of NEMA NU4 Image Quality for the 10 and 20 min summed frames for single centered and dual phantom cases. (A–C) Uniformity, Spill-Over ratio (SOR) and Recovery Coefficients for the centered and dual phantom positions, 10 min summed frame. (D–F) Uniformity, SOR and Recovery Coefficients for the single or dual phantom positions, 20 min summed frame
Summary
Preclinical Positron Emission Tomography (PET) allows the longitudinal study of a range of biological processes in disease models, as well as being invaluable in the screening of novel diagnostic/theranostic PET probes. It is increasingly common for preclinical PET centers to scan multiple animals simultaneously in order to increase the cost-efficiency and throughput of studies, Multiple Animal Image Quality SuperArgus2R especially with the use of short-lived PET isotopes such as [11C], or where statistical requirements demand large study groups for the correct powering of experiments [1, 2]. Increased throughput in small animal preclinical studies using positron emission tomography leads to reduced costs and improved efficiency of experimental design, the presence of multiple off-centre subjects, as opposed to a single centered one, may affect image quality in several ways
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
