The effect of activity outside the field of view on image quality for a 3D LSO-based whole body PET/CT scanner

摘要: The purpose of this study was to quantify the influence outside field view (FOV) activity concentration (A(c)(,out)) on noise equivalent count rate (NECR), scatter fraction (SF) and image quality a 3D LSO whole-body PET/CT scanner. contrast-to-noise ratio (CNR) figure merit used characterize PET scans. A modified International Electrotechnical Commission (IEC) phantom obtain SF counting rates similar those found in average patients. positioned at end IEC simulate an that extends beyond filled with (18)F (11 kBq mL(-1)) spherical targets, internal diameter (ID) ranging from 10 37 mm, had target-to-background 10. images were acquired background concentrations into FOV (A(c)(,bkg)) about 11, 9.2, 6.6, 5.2 3.5 mL(-1). emission scan duration (ESD) set 1, 2, 3 4 min. tube inside activities provide A(c)(,out) whole zero, half, unity, twofold fourfold one phantom. Plots CNR versus various parameters are provided. Multiple linear regression employed effects CNR, adjusted for presence variables (sphere ID, A(c)(,bkg) ESD) related CNR. same as reduces peak NECR 30%. increase is marginal (1.2%). diminishes significantly increasing activity, range explored. ESD have weight accounting variance. Thus, experimental law adjusts can be devised. Recovery loss due elevated seems feasible by modulating individual bed positions according A(c)(,out).