Darryl McClymont1, Irvin Teh1, Hannah Whittington1, Vicente Grau2, and Jurgen Schneider1
1Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, 2Department of Engineering Science, University of Oxford, Oxford, United Kingdom
Non-Gaussian diffusion MRI allows the quantification of diffusion
signals that deviate from mono-exponential decay. In cardiac MRI, very little
has been reported on non-Gaussian models. In this work, the diffusion tensor,
stretched exponential, bi-exponential, and diffusion kurtosis models were fit
to data from fixed rat hearts. Performance was measured using the Akaike
Information Criterion (AIC). All models demonstrated the presence of
non-Gaussian diffusion, particularly in the right ventricle. The bi-exponential
model fit the data best and had the lowest AIC. Non-Gaussian diffusion was greater
perpendicular, rather than parallel, to cardiac fibers, corresponding to greater
restrictions to diffusion.
