Irvin Teh1, Samo Lasič2,3, Henrik Lundell3, Beata Wereszczyńska1, Matthew Budde4, Erica Dall'Armellina1, Nadira Yuldasheva1, Filip Szczepankiewicz5,6,7, and Jürgen E. Schneider1
1Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom, 2Random Walk Imaging, Lund, Sweden, 3Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark, 4Department of Neurosurgery, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States, 5Clinical Sciences, Lund University, Lund, Sweden, 6Harvard Medical School, Boston, MA, United States, 7Brigham and Women's Hospital, Boston, MA, United States
1Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom, 2Random Walk Imaging, Lund, Sweden, 3Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark, 4Department of Neurosurgery, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States, 5Clinical Sciences, Lund University, Lund, Sweden, 6Harvard Medical School, Boston, MA, United States, 7Brigham and Women's Hospital, Boston, MA, United States
Multidimensional diffusion MRI has the
potential to improve specificity in cardiac diffusion MRI beyond that
achievable with DTI. We present initial data in ex vivo mouse hearts at 7T,
that demonstrate the feasibility and potential of the technique.
Figure 3. Parameter maps
in control and isoproterenol hearts generated by fitting the (top-bottom) DTI,
covariance and gamma models scaled to [0 1]. DTI and covariance methods yield
mean diffusivity (MD in µm2/ms) and fractional anisotropy (FA).
Additional maps of microscopic fractional anisotropy (µFA), mean anisotropic
kurtosis (MKa), mean isotropic kurtosis (MKi), mean total kurtosis (MKt), microscopic
orientation coherence (Cc) and normalised size variance (CMD) are shown, along
with ROI masks (bottom right).
Figure
2. (Left) Normalised signal attenuation curves for spherical and linear tensor
encoding in myocardium (myo) of the control heart and gel. Non-monoexponential
behaviour of gel at high b was governed by noise. (Right) Zoomed section
showing signal kurtosis attributable to isotropic and anisotropic components
(MKi; MKa). (Top) Example LTE images averaged across diffusion directions.
