[18F]FDG administered activity reduction capabilities of a 32-cm axial field-of-view solid-state digital bismuth germanium oxide PET/CT system while maintaining EARL compliance

Abstract

Purpose: To assess the lower [18F]FDG limit in administered activity and/or scan time reduction capabilities of a digital-BGO 32-cm axial field-of-view PET system while being compliant with current and updated EANM Research Ltd Fluorine-18 accreditation specifications (EARL1 and EARL2). Methods: EARL1 and EARL2 compliance of the digital-BGO system (Omni Legend 32 cm) was tested for several reconstructions, including those that apply precision deep learning-based image enhancement (PDL) as postprocessing,

using the calibration QC and NEMA IEC phantom measurements. The image quality QC scan was

repeated every hour for 7 h, with each subsequent hour representing a lower administered activity, and

reconstructed for various times per bed position, i.e. 30, 60, 120, 180, and 300 s. For each of the image quality QC images, coefficient of variation (COV) of the background compartment, and mean, maximum and peak activity concentration recovery coefficients (RCmean, RCmax and RCpeak) of differently-sized spheres were calculated and compared to current and updated EARL accreditation specifications. Results: When we apply 1 min per bed position for PET acquisition, [18F]FDG administration can be reduced by a factor of ~ 4 for EARL1, by a factor of ~ 8 for EARL2 (2 mm voxels) and by a factor of ~ 4 for EARL2 (4 mm voxels) using both standard reconstructions and PDL post-processing compared to current EANM recommendations for [18F]FDG administration (7 MBq•min•bed-1•kg-1). Conclusions: Reduction in [18F]FDG administered activity is possible by at least a factor 4 for 1 min/bed with the Omni Legend 32 cm PET/CT while maintaining EARL1 and EARL2 compliance.