Hi Jeff,
why do you say that one is bad? We don't resample, so neither one will be aligned with the atlas unless you apply the transform.
We are aware that the eTIV measures have more variability than we would like, and we're looking into it, but don't have a good solution from only T1 images.
cheers, Bruce On Thu, 4 Sep 2008, Jeff Sadino wrote:
Hello all,
According to aseg.stats, our ICV values fluctuate on the same subject across scans, sometimes by up to 10% I have been validating the talairach_with_skull.lta accuracy by comparing the nu_neck.mgz to the RB_all_withskull_2006-02-15.gca template. I read on the boards that it is not all that necessary that the brains match, that it is more important for the skulls to match. The RB is blurred (I don't fully understand where the RB comes from, I think from 22 subjects that the freesurfers combined into one?), so am I matching up the whitest areas of the RB to the skull on the nu_neck image? I noticed also that the bottom of the brains rarely match at all to the RB image...is this normal? Are there any other parts of the image that need to be checked for validity?
I attached two nu_noneck.mgz files, one was good and the other bad. Are these images typical?
Thank you for your help, Jeff
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