Matlab software version r2018a

A 2D multimodel direct inversion algorithm was used to reconstruct 2D MRE data processed by vendor-supplied built-in software.^{22 (link)} Magnitude, phase, confidence, colorized wave propagation, and elastogram stiffness images representing shear modulus were generated. A stiffness map with 95% confidence was also generated to exclude unreliable regions (Figure 1A). Magnitude images were used to trace the allograft parenchyma, which were later overlaid on the 95% confidence interval (CI) stiffness maps to extract regions of interest (ROIs). The mean stiffness from ROIs spanning a minimum of 3 coronal slices (excluding edge slices) was defined as the mean stiffness of the whole organ. All ROI tracings and calculations were done using ImageJ (v1.53, National Institutes of Health, Bethesda, MD) and MATLAB software version R2018a (The Mathworks, Inc., Natick, MA) by a research analyst (A.S.S.) blinded to the patient’s clinical and histopathologic results.