Clinical Implications of Different Image Reconstruction Parameters for Interpretation of Whole-Body PET Studies in Cancer Patients

The standardized uptake value (SUV) is the most commonly used parameter to quantify the intensity of radiotracer uptake in tumors. Previous studies suggested that measurements of 18F-FDG accumulation in tissue might be affected by the image reconstruction method, but the clinical relevance of these find-ings has not been assessed. Methods: Phantom studies were performed and clinical whole-body 18F-FDG PET images of 85 cancer patients were analyzed. All images were reconstructed using either filtered backprojection (FBP) with measured atten-uation correction (MAC) or iterative reconstruction (IR) with seg-mented attenuation correction (SAC). In a subset of 15 patients, images were reconstructed using all 4 combinations of IRSAC, IRMAC, FBPSAC, and FBPMAC. For phantom studies, a sphere containing 18F-FDG was placed in a water-filled cylinder and the activity concentration of that sphere wa