Related Experiment Video
Updated: Aug 6, 2026
Radiosynthesis, Quality Control, and Small Animal Positron Emission Tomography Imaging of 68Ga-Labelled Nano Molecules
Published on: October 4, 2024
Toward Trustworthy PET Radiomics: Quantitative Repeatability Analysis of 18F-FDG and 68Ga-PSMA Features under
Shu-Ju Tu1,2, Yi-Chen Wu1, Jing-Ren Tseng2,3,4
1Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan.
Background:
The reliability of PET radiomic features is fundamentally constrained by inherent stochastic noise originating from Poisson-distributed photon-counting statistics and additional fluctuations introduced by electronic signal processing. To assess its impact, we repeated PET scans under identical acquisition and reconstruction conditions to evaluate the consistency of radiomic feature measurements and quantify the noise-induced variability as a repeatability measure.
Materials And Methods:
An American College of Radiology-accredited (ACR) phantom was utilized to evaluate measurement variability in PET radiomic features under two scenarios: uniform (Experiment 1) and non-uniform (Experiment 2) radiotracer distributions, employing 18F-FDG and 68Ga-PSMA tracers. A total of 93 radiomic features across six categories were extracted using PyRadiomics. Each experiment was repeated ten times, and measurement variability was quantified using the coefficient of variation (CV). Features were benchmarked and classified into three quality grades of repeatability: Grade A (CV < 10%), Grade B (10% ≤ CV < 20%), and Grade C (CV ≥ 20%).
Results:
Experiment 1 identified 22 Grade A and 14 Grade C features, whereas Experiment 2 yielded 30 Grade A and 15 Grade C features. Notably, CV values exhibited substantial variability. In Experiment 1, CV ranged from 0.17% to 205% for 18F-FDG and from 0.14% to 140% for 68Ga-PSMA. Similarly, in Experiment 2, CV spanned from 0.16% to 230% for 18F-FDG and from 0.23% to 79% for 68Ga-PSMA.
Conclusion:
By isolating inherent stochastic noise, this study applied the coefficient of variation to evaluate measurement variability across repeated PET scans and benchmarked radiomic features into three repeatability quality categories. While some features demonstrated high noise resilience, others showed poor repeatability across repeated scans. These findings highlight the need to establish repeatability standards to guide the development of noise-robust features that support trustworthy imaging biomarkers for clinical applications.
Supplementary Information:
The online version contains supplementary material available at 10.1007/s13139-026-01008-5.
