Hi,
the minimum that we would advice are ~ 30 diffusion gradients. See previous posts on this.
Hope this helps.
Best regards-
Andreas
Dr. A. Bartsch
Dep. of Neuroradiology
Univ. of Wuerzburg
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Von: FSL - FMRIB's Software Library im Auftrag von Igor O. Korolev
Gesendet: Do 08.03.2007 00:07
An: [log in to unmask]
Betreff: [FSL] Fiber Tracking in FDT using DTI data with 6 directions
Dear Dr. Behrens,
Thank you for your rapid response regarding the FDT tutorial data. Now, I would like to ask about the FDT analysis of our team's data.
Specifically, our DTI data was acquired in only 6 directions (diffusion-weighted acquisitions) plus 1 B_zero, non-diffusion-weighted acquisition.
Given that it takes a minimum of 6 DTI acquisitions / gradient directions to compute a tensor, is it still statistically valid to use FDT / Probabilistic Tractography
to conduct fiber-tracking analysis of our data? That is, will we have enough acquired DTI data to reliably estimate the probability density function used for determining the
connectivity distributions? (it seems that NO). Or is it only valid to use FDT for conducting tractography in DTI data acquired in more than 6 directions?
Thank you for your help.
-Igor Korolev
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Igor O. Korolev
D.O./Ph.D. Program
College of Osteopathic Medicine
Neuroscience Program
Michigan State University
Email: [log in to unmask]
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