Hi,
this would be SIENA.
Note that SIENA works on the single-subject level but can be extended to
multiple subjects by
http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/SIENA/UserGuide#Voxelwise_SIENA_Stati
stics
However, the standard edge space mask is more a representation of the
outer brain "envelope" than of the sulci. Yet, atrophy initially widens
the sulci - with global shrinking lacking behind.
In other words, SIENAs voxelwise extension does not adequately cover the
sulci. This may be the reason why the results (De Stefano et al., 2003;
Battaglini et al., 2009; Smith et al., 2007; Majid et al., 2011; Kempton
et al., 2009; Streitbürger et al., 2012 and finally Bartsch et al., 2007)
look very similar for different (pseudo-)atrophy etiologies. There seems
to be a clear bias for the ventricular borders and outer brain "envelope".
Thus, you may want to try Freesurfers longitudinal stream along with LME
modeling if you want to look at cortical thinning at the group level.
At the single subject level, SIENAS local estimates (the edge flow images)
work quite well and, most importantly, are NOT subject to the above bias.
HTH,
Andreas
Am 29.10.13 12:19 schrieb "Bernardo Jose Alves Ferreira Martins" unter
<[log in to unmask]>:
>Hi FSL experts,
>
>Is there a tool to evaluate local atrophy progression within-subject?
>
>Any feedback would be appreciated,
>
>Thanks,
>Bernardo.
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