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FIG 3. Posterior aspects of the same image section as in Figure 2 show white matter tracts superimposed on the images in A–F magnified from the rectangular region-of-interest (solid rectangles). Although the FLAIR DTI tractogram shows more tracts in the splenium of the corpus callosum (B and dashed oval in F, with more consistent fiber directions) than the conventional DTI tractogram (A and dashed oval in E, with less consistent fiber direction near the lateral ventricle), false tracts are found in the occipital lobes (B).
A and B, Images obtained with b = 0 s/mm2 by using the EZ-tracing algorithm.
C and D, FA maps in gray scale displayed in identical window level obtained by using conventional (C) and FLAIR DTI (D). D is noisier than C, suggesting uncertainty in FA values.
E and F, Vector-encoded FA maps show that the false tracts in B are due to incidentally consistent orientations of the eigenvectors (rectangle in F), which is absent in E (rectangle in E). Red indicates left-right; green, anteroposterior; and blue, superoinferior.
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