Hi all,
I am trying to use the PDD algorithm described by D. C. Alexander et
al, IEEE Trans on medical Imaging, 2001 . It is an algorithm that is used
to preserve orientational information that DTI images contain, when they
are registered to another space than the original one of the scanner. It
actually rotates the eigenvectors of the Diffusion tensor in the new
coordinate system.
I am a bit confused by the description of the algorithm in the above
paper. Has anybody used this algorithm? I am assuming that for each voxel
of a DT image, the original eigenvectors e1,e2,e3 are transformed to
v1,v2,v3 eigenvectors through a Rotation Matrix R. What is the
relationship between ei and vi? vi=Rei?
It is not very clear in the paper and it gets even more confusing in a
more recent paper (Coulon, Alexander, Arridge, Medical Image Analysis,
2004), where there is a short description of the algorithm.
Thank you in advance,
Stamatis
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