Fig. 3.

The effect of decreasing image resolution at the apex of heart #2. a An apical long-axis view of the 3D data acquired at isotropic 100 μm resolution. Voxels are coloured by helix angle. As helix angles are poorly defined at the apex, the projection of the primary eigenvector onto the image plane is also displayed. b The same slice as in a), re-sampled at isotropic 400 μm resolution. c The same data as in a-b), resampled to 400×400×1200 μm. The range of the helix angle and heterogeneity of vector orientations in the high-resolution image is progressively lost with decreasing resolution