Abstract
Background: Recently developed dynamic whole-body PET/CT (D-WB PET/CT) protocols allow for measurements of potentially more precise metabolic parameters than the commonly used semiquantitative SUV. Most notable is the metabolic rate of FDG uptake (MRFDG), which reflects quantitative glucose uptake into tissues and organs. However, data on the reproducibility of MRFDG measurements are scarce, particularly in patients with perturbed glucose homeostasis such as type 2 diabetes. We therefore aimed to evaluate the test-retest repeatability of both MRFDG and SUV in these patients. Results: Fifteen participants (mean age 71 ± 7 years; 2 females) with type 2 diabetes underwent a short 20-minute [18F]FDG D-WB PET/CT after 6 h fasting on two consecutive days. Both SUV and MRFDG images were reconstructed from D-WB PET/CT data obtained 60–80 min post-injection of [18F]FDG. MRFDG and SUV data were measured in organs and tissues, and repeatability was assessed with Bland-Altman analysis, intraclass correlation coefficients (ICC), repeatability coefficients (RPC) and coefficients of variation (wCV). There was high repeatability of both SUVmean and MRFDG−mean in all measured organs (ICC range: 0.65–0.95 for SUVmean and 0.66–0.94 for MRFDG−mean). SUVmean generally demonstrated higher reliability (ICC) and lower variability (%RPC and %wCV) when compared to MRFDG−mean. However, MRFDG test-retest variation was < 19% in most analysed tissues, demonstrating that MRFDG may be used as a precise marker of treatment response. Conclusion: This study demonstrates that MRFDG calculated from D-WB PET/CT exhibit high repeatability, comparable to SUVs across most organs in patients with type 2 diabetes.
| Original language | English |
|---|---|
| Article number | 56 |
| Journal | EJNMMI research |
| Volume | 15 |
| Issue | 1 |
| ISSN | 2191-219X |
| DOIs | |
| Publication status | Published - Dec 2025 |
Keywords
- Diabetes
- Dynamic whole-body PET
- FDG
- PET/CT
- Parametric imaging
- Test-retest