title: Quantitative carotid PET/MR imaging: clinical evaluation of MR-Attenuation correction versus CT-Attenuation correction in (18)F-FDG PET/MR emission data and comparison to PET/CT.
abstract: Current PET/MR systems employ segmentation of MR images and subsequent assignment of empirical attenuation coefficients for quantitative PET reconstruction. In this study we examine the differences in the quantification of (18)F-FDG uptake in the carotid arteries between PET/MR and PET/CT scanners. Five comparisons were performed to asses differences in PET quantification: i) PET/MR MR-based AC (MRAC) versus PET/MR CTAC, ii) PET/MR MRAC versus PET/CT, iii) PET/MR MRAC with carotid coil versus PET/MR MRAC without coil, iv) PET/MR MRAC scan 2 versus PET/MR MRAC scan 1, and v) PET/MR CTAC versus PET/CT. Standardized uptakes values (SUV) mean and SUV maximum were calculated for six regions-of-interests: left and right carotid arteries, left and right lungs, spine and muscle. Pearson's Correlation and Bland-Altman plots were used to compare SUV mean and maximum within each ROI of each patient. PET/MR emission data reconstructed with MRAC versus PET/MR emission data reconstructed with CTAC had percent differences of SUV mean ranging from -2.0% (Absolute Difference, -0.02) to 7.4% (absolute difference, 0.06). Percent differences within the carotid arteries proved to correlate well with differences of SUV mean of 5.4% (Absolute Difference, 0.07) in the left carotid and 2.7% (Absolute Difference, 0.03) in the right carotid. Pearson's correlation and Bland-Altman of PET/MR with MRAC versus PET/MR with CTAC showed high correlation between SUV mean (R(2)=0.80, mean difference 0.03 ± 0.18 SUV, p=0.3382), demonstrating excellent correlation within ROIs analyzed. The results of this study support the use of (18)F-FDG PET/MR for quantitative measure of inflammation in the carotid arteries.
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Biomedical Engineering, The City College of New York New York.
authors.forename: Jason
authors.initials: J
authors.lastname: Bini
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Radiology, Icahn School of Medicine at Mount Sinai New York, New York.
authors.forename: Philip M
authors.initials: PM
authors.lastname: Robson
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Radiology, Icahn School of Medicine at Mount Sinai New York, New York.
authors.forename: Claudia
authors.initials: C
authors.lastname: Calcagno
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Biomedical Engineering, The City College of New York New York.
authors.forename: Mootaz
authors.initials: M
authors.lastname: Eldib
authors.affiliation: Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Radiology, Icahn School of Medicine at Mount Sinai New York, New York ; Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josée and Henry R. Kravis Cardiovascular Health Center, Icahn School of Medicine at Mount Sinai New York, New York.
authors.forename: Zahi A
authors.initials: ZA
authors.lastname: Fayad
keywords: PET/CT; PET/MR; attenuation correction; cardiovascular; carotid arteries