Andrew Tyler1,2, Justin Y C Lau1, Jane Ellis1, Jack J Miller1,2,3, Paul A. Bottomley4, Christopher T Rodgers1,5, Damian J Tyler1,2, and Ladislav Valkovic1,6
1Oxford Centre for Clinical Cardiac Magnetic Resonance Research, University of Oxford, Oxford, United Kingdom, 2Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom, 3Department of Physics, University of Oxford, Oxford, United Kingdom, 4The Division of MR Research, Johns Hopkins Medicine, Baltimore, MD, United States, 5Wolfson Brain Imaging Centre, University of Cambidge, Cambridge, United Kingdom, 6Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
1Oxford Centre for Clinical Cardiac Magnetic Resonance Research, University of Oxford, Oxford, United Kingdom, 2Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom, 3Department of Physics, University of Oxford, Oxford, United Kingdom, 4The Division of MR Research, Johns Hopkins Medicine, Baltimore, MD, United States, 5Wolfson Brain Imaging Centre, University of Cambidge, Cambridge, United Kingdom, 6Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
31P compartmentalized
spectroscopy techniques at 7T can achieve a significantly higher SNR
than a CSI acquisition, for
the same acquisition time, while improving inter-scan
reproducibility and providing similar cardiac
PCr/ATP ratio.
Figure 2: (A)
A sample segmentation map of one slice of the heart, showing (blue)
chest wall, (orange) heart and (green) other compartments, and (black) the midseptal voxel (64% threshold of voxel PSF) used in the short AW CSI reconstruction. (B) Sample spectra for
each compartment in (A) reconstructed using the SLAM
algorithm and AW acquisition. (C) Fit, using the OXSA toolbox of the
heart compartment spectra in (B). (D) SLIM and SLAM reconstruction of
heart compartment in (A) with AW data and the mid-septal voxel of the
short AW CSI reconstruction. Spectra in B and D are normalized by
noise.
Figure 4: Box-plot showing PCr SNR values for each acquisition, median and IQR
indicated by box. * indicates significant difference to midseptal
CSI reconstruction (Wilcoxon
signed-rank paired, α=0.05/6, P-values above box-plot). SLAM/SLIM reconstructions which use the same data
acquisition as the midseptal
reconstruction are highlighted.
