Dear FreeSurfer experts,
We have a question regarding the aparc output from the stats files, and
hopefulle you can help us.
We have 4 independent groups, of about 30 subjects per group, all scanned using
the same protocal on the same MRI scanner. We ran the cross sectional
FreeSurfer (5.2.0, Linux centos4_x86_64) pipeline, and extracted the volume
information per person from the .stat files using Matlab. We transfered the
volume information into SPSS, to calculate the Means and Standard Deviations
per group.
We are interested in a couple of regions of interest (anterior + posterior
cingulate, OFC, parahippocamus and insula).
What strange is though, it that the means and standard deviations of 3 groups
are comparable across all regions, but the SDs of 1 group are very (very!)
large. This is not a group in which we expect brain atrophy or anything like
that. Below you see the SD values of all groups, with SD values up to four
times bigger in group 1!
1 2 3 4
caudal ACC 618 516 643 589
rostral ACC 1583 578 692 623
PCC 1942 721 616 749
OFC 2632 1345 1844 1652
parahip 1198 346 271 394
insula 1410 1033 1096 1017
The outliers are different subject in every region, and I checked the
parcellation output of them, that looks fine. We are wondering what could be
the cause of this, do you have any ideas?
Thank you in advance,
Kind regards,
Laura
________________________________
AMC Disclaimer : http://www.amc.nl/disclaimer
________________________________
_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.
