Hi,
Regarding FIRST, the models used to label the image model the structural
variation residual to the alignment. Given that in the preprocessing, all
the children's data was aligned to the MNI space template, they should
model the after alignment using this process. If a children's template had
been used, the variance in the models should be reduced. But it is
difficult to say whether a dedicated model would do better.
Cheers,
Brian
> Hi all,
>
> I would have two questions:
>
> 1.: Is it valid to use FIRST in children to measure subcortical structure
> volumes? Although the software uses labels that were constructed from both
> children and adults, the first_flirt step applies a registration to MNI
> 152 sub-
> cortical mask, which (I think) should not be used for children. Is ther
> anything
> that I can do to bypass this problem? Can somebody tell me what should be
> done in a different way for children during the method?
>
> 2.: FSL-VBM: I have a group of patients scanned on a 1.5 T Siemens machine
> with TR:21, TE:7 ms, voxel size 0.5-0.5-2 mm and a control group from the
> same scanner but slightly different parameters(TR:20, TE:5.58ms, Voxel
> size:
> 1-1-2 mm). Is it valid to compare them with vbm, does it worth to run the
> process? If not, is there any sollution?
>
> Thanks,
>
> Balint
>
>
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