Bert-Ram Sah1,2,3,4, Soleen Ghafoor3,4, Irene A Burger5,4,6, Edwin E G W Ter Voert5,4, Tetsuro Sekine5, Gaspar Delso5,7, Martin Huellner5,4, Konstantin J Dedes6,8, Andreas Boss3,4, Patrick Veit-Haibach5,3,4,9,10. 1. Department of Nuclear Medicine, University Hospital of Zurich, Zurich, Switzerland bert-ram.sah@usz.ch. 2. Department of Cancer Imaging, King`s College London, London, United Kingdom. 3. Department of Diagnostic and Interventional Radiology, University Hospital of Zurich, Zurich, Switzerland. 4. University of Zurich, Zurich, Switzerland. 5. Department of Nuclear Medicine, University Hospital of Zurich, Zurich, Switzerland. 6. Cancer Center Zurich, Zurich, Switzerland. 7. GE Healthcare, Waukesha, Wisconsin. 8. Department of Gynaecology, University Hospital of Zurich, Zurich, Switzerland. 9. Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada; and. 10. University of Toronto, Toronto, Ontario, Canada.
Abstract
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.
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.
Authors: Thomas A Hope; Zahi A Fayad; Kathryn J Fowler; Dawn Holley; Andrei Iagaru; Alan B McMillan; Patrick Veit-Haiback; Robert J Witte; Greg Zaharchuk; Ciprian Catana Journal: J Nucl Med Date: 2019-05-23 Impact factor: 10.057
Authors: Amy M Fowler; Manoj Kumar; Leah Henze Bancroft; Kelley Salem; Jacob M Johnson; Jillian Karow; Scott B Perlman; Tyler J Bradshaw; Samuel A Hurley; Alan B McMillan; Roberta M Strigel Journal: Radiol Imaging Cancer Date: 2021-01-15
Authors: Ian Alberts; Christos Sachpekidis; George Prenosil; Marco Viscione; Karl Peter Bohn; Clemens Mingels; Kuangyu Shi; Ali Ashar-Oromieh; Axel Rominger Journal: Ann Nucl Med Date: 2021-02-07 Impact factor: 2.668