Thanks for the response, Steve. Really what I'd like to do is directly identify a particular tract on the FA maps as opposed to relying on tractography to identify it. Right now I'm getting results by identifying two seeds in anatomical space and connecting them, and I'm getting good results on some subjects but sometimes no track on others. I thought the atlas was something like the freesurfer atlas but for DTI data where I could create a label and use that as a mask to get an average FA. I will look more carefully at the atlas and see if it maybe would inform me of how to identify my seed points in my FA maps for tractography. Thanks!
Kristen
-----Original Message-----
From: FSL - FMRIB's Software Library on behalf of Steve Smith
Sent: Thu 2/21/2008 2:45 AM
To: [log in to unmask]
Subject: Re: [FSL] DTI-based White Matter Atlas
Hi - the atlases are there as a guide for what structures are where -
but they may not exactly related to a given new individual's scan.
Using the masks directly in the context of TBSS results makes some
sense, but for tractography, if you have already got your tracts, this
implied that you chose your seed/target voxels/masks carefully and so
presumably already have a strong idea of what tracts you are looking
for? So I'm not quite sure how you are wanting to then use the atlases?
Cheers.
On 19 Feb 2008, at 21:18, Lindgren, Kristen, Ann wrote:
> Hello. I am interested in using the JHU DTI-based white-matter
> atlases
> to obtain the average FA values of various tracts. I've created masks
> and gotten average FAs from our DTI using tractography, but I'm
> wondering if there is documentation on how to use the available
> atlases
> to do this. Thanks and hopefully I explained that clearly!
>
> Kristen
>
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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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