Fig 1.
The corpus callosum used to calculate the FWHM.
Fig 2.
The relationship between the SNR and the b-value.
(a) The SNR of corpus callosum. (b) The SNR of centrum semiovale.
Fig 3.
The FWHM of the diffusion ODF from S1 at five b-values.
(a) Distribution of the diffusion ODF measured by SPFI for S1 at five b-values. The x-axis shows the colatitudes, where 0° indicates that the orientation is parallel to that of the principal direction. (b) The FWHM of the ODF profile measured in (a). (*) indicates statistically significant differences between groups (p < 0.001).
Fig 4.
The group FWHM of the diffusion ODF from all eight subjects at five b-values.
(*) indicates statistically significant differences between groups (p < 0.001).
Fig 5.
The FWHM of the fiber ODF from S1 at five b-values.
(a) Distribution of the fiber ODF measured by CSD for S1 at five b-values. The x-axis shows the colatitudes, where 0° indicates that the orientation is parallel to that of the principal direction. (b) The FWHM of the ODF profile measured in (a). (*) indicates statistically significant differences between groups (p < 0.001).
Fig 6.
The group FWHM of the fiber ODF from all eight subjects at five b-values.
Fig 7.
The angular difference in the diffusion ODF obtained with SPFI between each pair of neighboring b-values.
(a) The angular difference for one-directional situations. (b) The angular difference for two-directional situations.
Fig 8.
The angular difference in the diffusion ODF obtained with SPFI between each pair of b-values.
(a) The angular difference for one-directional situations.(b) the angular difference for two-directional situations. The color in the grid indicates the angular difference in the ODF between the two b-values in the x-axis and the y-axis.
Fig 9.
The angular difference in the fiber ODF obtained with CSD between each pair of neighboring b-values.
(a) The angular difference for one-directional situations. (b) The angular difference for two-directional situations.
Fig 10.
The angular difference in the fiber ODF obtained with CSD between each pair of b-values.
(a) The angular difference for one-directional situations. (b) The angular difference for two-directional situations. The color in the grid indicates the angular difference in the ODF between the two b-values in the x-axis and the y-axis.
Fig 11.
The diffusion ODFs of the DWI data from different b-values in the centrum semiovale.
The b-values for (A)-(E) were 650, 1000, 1500, 2000, 2500 s/mm2, respectively. The top-left figure indicates the centrum semiovale by a red rectangle. The three specially marked voxels in (a)-(c) are given a closer look in Fig. 12.
Fig 12.
The diffusion ODFs of three voxels (those marked in Fig. 11A-C) at different b-values.
The three voxels contain different numbers of fiber directions. Each row illustrates the ODFs of the same voxel at different b-values. The yellow sticks represent the principal peak(s) of the ODFs.
Fig 13.
The fiber ODFs of the DWI data from different b-values in the centrum semiovale.
The b-values of (A)-(E) = 650, 1000, 1500, 2000, 2500 s/mm2, respectively. The top-left figure indicates the centrum semiovale by a red rectangle. The three specially marked voxels in (a)-(c) are given a closer look in Fig. 14.
Fig 14.
The fiber ODFs of three voxels (also marked in Fig. 13A-C) at different b-values.
The three voxels contain different numbers of fiber directions. Each row illustrates the ODFs of the same voxel at different b-values. The yellow sticks represent the principal peak(s) of the ODFs.