Hi there,
Long time:). Well I wrote to the list several times regarding high FA values I got when performing DTI analysis. Today we know that the problem was an additional direction (we had 17 directions instead of 16 - we used a Philips scanner,1.5T). So we deleted the additional slices and the high values indeed disappeared, but then another problem came up (tried several subjects so the problem is not specific to a subject) -
I noticed an artifact that I can't explain - please see the attached pictures.
This artifact existed even before I deleted the additional slices, also - I see the artifact also when loading the masked volume...It is cyclic - run over all slices...
any ideas ?
I'm using version 5.2 and I know the command lines are correct (send it to u in the past).
Thanks for your help
Rotem
Sorry, can't open the image.
On Sun, 23 Jun 2013, Rotem Saar wrote:
Hi there,
Long time:). Well I wrote to the list several times regarding high FA values I got when performing DTI analysis. Today we know that the problem was an additional direction (we had 17 directions instead of 16 - we used a Philips scanner,1.5T). So we deleted the additional slices and the high values indeed disappeared, but then another problem came up (tried several subjects so the problem is not specific to a subject) -
I noticed an artifact that I can't explain - please see the attached pictures.
This artifact existed even before I deleted the additional slices, also - I see the artifact also when loading the masked volume...It is cyclic - run over all slices...
any ideas ? I'm using version 5.2 and I know the command lines are correct (send it to u in the past).
Thanks for your help
Rotem
freesurfer@nmr.mgh.harvard.edu