[Mristudio-users] question about eigenvalues/vectors

[Katherine L. Ragland]

Hello-

I am a fourth year medical student at the University of Mississippi Medical Center working with Dr. Judy James.  We have been using your DTIStudio software for fiber tracking in the fetal brain.  I would like to preface my questions by saying my current knowledge of DTI, eigenvalues, eigenvectors, etc. is quite limited.  If I say something incorrectly, please let me know!

My questions for you deal with eigenvalues and eigenvectors.  

1)  What is the clinical applicability of these measurements?  For example, does a shorter primary eigenvector signify a loss of anisotropy and possibly decreased myelination?  What can one infer from increasing or decreasing trends in eigenvalues?  

2)  Do the eigenvalue 0 and eigenvector 0 correspond to the primary value/vector parallel to axon fibers?

2)  How do you calculate the primary eigenvector from the statistics derived from DTIstudio?  (the 3 eigenvectors are given as x, y, and z coordinates)

I appreciate any insight you can give.

Thank you very much for this software and your time in reading this.

Sincerely,

Katie Ragland

Individuals who have received this information in error or are not authorized to receive it must promptly return or dispose of the information and notify the sender. Those individuals are hereby notified that they are strictly prohibited from reviewing, forwarding, printing, copying, distributing or using this information in any way.