 |
 |
Thanks a lot, Saad! 2009/12/1 Saad Jbabdi <[log in to unmask]> > Yes, the results are always stored in seed space - which in your case is > standard space. > > Saad. > > > On 1 Dec 2009, at 12:33, hudong x wrote: > > Dear all, > > Maybe this is a very easy or stupid question for some people. But I was > really confused. > > I was doing fiber tracking using ProbtrackX of Fdt. I used a single mask as > the seed, and specified one waypoint mask and one termination mask. All the > three masks were in standard space. I then chose 'seed space is not > diffusion' and specified the transformation matrix (standard2diff) and > reference imge (MNI_T!_152_brain). > > My question is: in this way of fiber tracking, which space are the resulted > fibers in? Several guys in my group told me that the fibers I got should > still be in the diffusion space. FSLVIEW all told me the fibers were in > "aligned-anatomical space" when I open them. > However, I found that the fibers matched the standard FA image white matter > better than the native FA image when I contrast these two. And the most > weird thing is, after I used the FLIRT to transform these fibers into the > standard space, the fibers jumped to the right hemisphere and part of them > were out the brain! > > I then tried the FLIRT on other images which were already in the standard > space. I got almost the same weird results. > > Thus I guess these fibers I got were already in the standard space even > FSLVIEW told me they were not? > > Any Help will be highly appreciated. > > > Best regards, > Huadong > > -- > ------------------------------------------------------------ > H Xiang PhD Candidate > Neurocognition of language & MR-Methods Group > Donders Institute for Brain, Cognition and Behaviour, > Centre for Cognitive Neuroimaging > Radboud University Nijmegen > PO Box 9101 > 6500 HB NIJMEGEN > The Netherlands > http://www.ru.nl/neuroimaging > &------- > Founding Webmaster > I Love Brain Science > http://52brain.com > > > -- > Saad Jbabdi > University of Oxford, FMRIB Centre > > JR Hospital, Headington, OX3 9DU, UK > +44 (0) 1865 222466 (fax 717) > www.fmrib.ox.ac.uk/~saad >