Noel Naughton^{1}, Nicholas Gallo^{2}, Marcella Viacik^{2}, Aaron Anderson^{1}, Bradley Sutton^{1}, and John Georgiadis^{1,2}

We present a method to estimate microstructural parameters of a decellularized pig myocardium using a two-compartment exchange model. We also show that the estimated parameters are in good agreement with other values found in the literature.

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FIGURE 1: Cross-sectional T2 weighted image with directions
of primary eigenvector overlaid. The structural organization of the decellularized
myocardium is clearly visible.

TABLE 1: Mean eigenvalues and standard deviations from
experimental data as well as eigenvalues from the numerical model using the
mean of each fitted parameter. The experimental and numerical eigenvalues are
in good agreement.

TABLE 2: Fitted mean parameters for both heart sections as
well as standard deviations. Bold relates to parameter sets which were normally
distributed according a Shapiro-Wilk test. Diffusion coefficients are in units
of mm2/ms,
exchange time is in units of seconds and inclusions fraction is dimensionless.

TABLE 3: Selected correlation values (|R| > 0.4) between parameters. The correlation between the Din and Dex suggests the influence of the underlying aqueous solutions while correlations between Din,a and Din,t as well as Dex,1 and Dex,2 show that they are reflections of the same free diffusion coefficient which is restricted in certain directions. Dex,3 and inclusions fraction can be interpreted as the diffusion though the ECM effected by the membrane so a change in the amount of myocytes will effect this diffusion coefficient and also a change in the cell size will effect both exchange time and packing fraction.