RT Journal Article SR Electronic T1 Feasibility of 18F-FDG Dose Reductions in Breast Cancer PET/MRI JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1817 OP 1822 DO 10.2967/jnumed.118.209007 VO 59 IS 12 A1 Bert-Ram Sah A1 Soleen Ghafoor A1 Irene A. Burger A1 Edwin E.G.W. ter Voert A1 Tetsuro Sekine A1 Gaspar Delso A1 Martin Huellner A1 Konstantin J. Dedes A1 Andreas Boss A1 Patrick Veit-Haibach YR 2018 UL http://jnm.snmjournals.org/content/59/12/1817.abstract AB The goal of this study was to determine the level of clinically acceptable 18F-FDG dose reduction in time-of-flight PET/MRI in patients with breast cancer. Methods: Twenty-six consecutive women with histologically proven breast cancer were analyzed (median age, 51 y; range, 34–83 y). Simulated dose-reduced PET images were generated by unlisting the list-mode data on PET/MRI. The acquired 20-min PET frame was reconstructed in 5 ways: a reconstruction of the first 2 min with 3 iterations and 28 subsets for reference, and reconstructions simulating 100%, 20%, 10%, and 5% of the original dose. General image quality and artifacts, image sharpness, image noise, and lesion detectability were analyzed using a 4-point scale. Qualitative parameters were compared using the nonparametric Friedman test for multiple samples and the Wilcoxon signed-rank test for paired samples. Different groups of independent samples were compared using the Mann–Whitney U test. Results: Overall, 355 lesions (71 lesions with 5 different reconstructions each) were evaluated. The 20-min reconstruction with 100% injected dose showed the best results in all categories. For general image quality and artifacts, image sharpness, and noise, the reconstructions with a simulated dose of 20% and 10% were significantly better than the 2-min reconstructions (P ≤ 0.001). Furthermore, 20%, 10%, and 5% reconstructions did not yield results different from those of the 2-min reconstruction for detectability of the primary lesion. For 10% of the injected dose, a calculated mean dose of 22.6 ± 5.5 MBq (range, 17.9–36.9 MBq) would have been applied, resulting in an estimated whole-body radiation burden of 0.5 ± 0.1 mSv (range, 0.4–0.7 mSv). Conclusion: Ten percent of the standard dose of 18F-FDG (reduction of ≤90%) results in clinically acceptable PET image quality in time-of-flight PET/MRI. The calculated radiation exposure would be comparable to the effective dose of a single digital mammogram. A reduction of radiation burden to this level might justify partial-body examinations with PET/MRI for dedicated indications.