Is the standard uptake value (SUV) appropriate for quantification in clinical PET imaging? - Variability induced by different SUV measurements and varying reconstruction methods

- Point spread function reconstruction increases SUV systematically.
- PET quantification in lesions <5 ml is very prone to deviations.
- SUVpeak is the average uptake value in a fixed ROI around the maximum pixel.
- SUVpeak is more reproducible than SUVmax and SUVmean.

IntroductionPET quantification using the standard uptake value (SUV) is very prone to variations by technical factors of the scanner system and patient specific characteristics. Aim of the study was to investigate the reproducibility of SUV values between different measures and different reconstruction algorithms in a PET/CT scanner of the newest generation.MethodsThe time-of-flight PET datasets of 27 consecutive oncological patients were reconstructed with OSEM3D in two different matrix sizes (200 × 200 and 400 × 400) as well as in a matrix size of 400 × 400 and additional point-spread-reconstruction. The standardized uptake values SUVmax, SUVmean and SUVpeak in 60 lesions were compared concerning their variability in the three reconstructions.ResultsThe addition of point-spread-reconstruction causes a significant increase of SUV values in comparison to OSEM 3D. SUVpeak showed the highest reproducibility between the different reconstruction algorithms. The variability of SUVmax and SUVmean increases in small lesions <5 ml, while SUVpeak remains more stable.ConclusionSUVmax, SUVmean and SUVpeak can be used for PET quantification in principle. However, quantification of small lesions is difficult. SUVpeak is the most robust method when using varying reconstruction methods, especially in small lesions.