Hi,
I recently acquired and analyzed coronal DTI data using a 72 direction DTI pulse sequence on a
Siemens scanner. After analyzing the data I saw that the color coded FA maps looked fine; mid-
sagittal corpus callosum section were depicted in red, corticospinal tract in blue, longitudinal
fasciculus in green, etc. When I looked at the principle eigenvectors I saw that they were not correct
and appeared quite different in comparison to DTI data obtain axially. To check if the eigenvectors
did not simply appear different because of very small differences in voxel dimensions between axial
and coronal DTI dataset, I performed probabilistic mapping of the corpus callosum and got wierd
results. To analyze my coronal data I didn't reslice or reorient the volumes and I used the bvec and
bval files extracted from the coronal DTI dataset and not the axial dataset. Is there an explanation of
why the color coded FA maps would look fine and at the same time V1 maps are incorrect. I can
send images if needed.
Thanks,
Jaymin
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