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. Author manuscript; available in PMC: 2016 Jan 31.
Published in final edited form as: Neuroimage. 2014 Nov 15;106:391–403. doi: 10.1016/j.neuroimage.2014.11.015

Figure 2.

Figure 2

Standard DKI images and KANDO maps for a single axial slice. The first row shows the T2-weighted (b = 0) image together with the mean diffusivity (MD = D̄), FA, and MK maps. The second row shows the total neurite water fraction for Examples 1, 2, and 3. The results obtained using both Kmax (Ex1a) and K⊥,max (Ex1b) to estimate f1 are given with Example 1. For these same four cases, the third row shows the intrinsic intra-neurite diffusivity, and the fourth row shows the extra-neurite mean diffusivity (MDe = D̄e). In Example 1, voxels included in ROI 1 are displayed in color; in Example 2, voxels included in ROI 2 are displayed in color; in Example 3, voxels included in ROI 3 are displayed in color. The maps for Ex1a and Ex1b are nearly identical, demonstrating that choice of whether to use Kmax or K⊥,max to estimate f1 is of minor practical significance. The intrinsic intra-neurite diffusivity in Example 3 is set a priori to a value of D* = 1.0 μm2/ms. The other KANDO maps are calculated by minimizing the cost function of Eq. (9). The calibration bars for the diffusivities are in units of μm2/ms, while the remaining quantities are dimensionless.