Hi,
>Second, most of my FA intensity-modulated color maps look fine after
>reconstructing the diffusion tensors in DTIFIT,
>but a few have strange red/interhemispheric hyperintensities that are
>apparent in the sagittal view, usually in parietal Brodmann areas 7 and
>19.
this sounds like the vibration artefact, see Gallichan D et al, 2010, Hum
Brain Mapp, 31(2):193-202
Cheers,
Andreas
Am 05.07.12 09:47 schrieb "SUBSCRIBE FSL Anonymous" unter
<[log in to unmask]>:
>Sorry, don´t know why the first thing that shows up is html. Here´s the
>post.
>
>Hello All,
>
>I have a couple newbie questions regarding the brain extraction and FA
>map results.
> First, several of my images are left with holes or gouges around the
>exterior of the brain mask after the BET step and I´ve seen responses to
>previous posts that mention lowering the brain/non-brain %threshold,
>using voxel-wise regressors to account for these lost voxels, manually
>creating the mask, etc; what is the best option for someone relatively
>new to the software to modify these masks? I´m trying to attach an
>example of one of the faulty masks below.
> Second, most of my FA intensity-modulated color maps look fine after
>reconstructing the diffusion tensors in DTIFIT, but a few have strange
>red/interhemispheric hyperintensities that are apparent in the sagittal
>view, usually in parietal Brodmann areas 7 and 19. Any reasons why this
>is coming up? Could the intensity have been poorly regulated in a
>previous step? Again, will try to attach a picture.
> All files are 4D NIFTI files from T2 weighted images (Siemens 3T).
>
>Thanks.
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