Departments of aRadiology bMedical Oncology cNuclear Medicine, Radboud University Medical Center, Nijmegen dDepartment of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
The aim of the study was to compare standardized uptake values (SUVs) in liver tissue obtained using whole-body unenhanced low-dose computed tomography (CT) with those obtained using contrast-enhanced high-dose CT for PET attenuation correction in PET/CT scanning.Ten patients scheduled for F-FDG PET and contrast-enhanced CT of the abdomen were included in this study. PET data were corrected for attenuation using both unenhanced low-dose CT images and contrast-enhanced high-dose CT images. Differences in SUVmean and SUVmax were compared in three liver regions.The average SUVmean and SUVmax of all regions were 2.43 and 2.91 g/cm in the unenhanced data set and 2.53 and 3.17 g/cm in the enhanced data set, respectively.SUVmean and SUVmax were significantly elevated in liver tissue when using PET images corrected for attenuation with contrast-enhanced high-dose CT compared with PET images corrected with unenhanced low-dose CT. Although the differences may not be relevant in daily clinical practice, unenhanced and contrast-enhanced CT should not be selected randomly for attenuation correction if exact quantitative results are required.