Dear SPM users
After segmentation one can see the means of the GM, WM, CSF segments
in the graphic window of SPM2. I think that this value is the mean voxel
intensity of the corresponding segment.
I have logitudinal data from 4 different years and intend to do VBM.
But I have seen that the mean voxel intensities of my segments differ
extremely.
e.g. GM / WM / CSF segments from 2004: 253 / 348 / 107
e.g. GM / WM / CSF segments from 2003: 30 / 41 / 13
Is it possible and scientifically valid to compare segments with such
different
voxel intensities using VBM?
Thanks a lot in advance
Best regards
Juergen
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Juergen Haenggi, Ph.D. student
Psychiatric University Hospital
Division of Psychiatry Research
University of Zurich, Switzerland
P.O. Box 1931
Lenggstrasse 31, 8032 Zurich
0041 44 384 26 10 (office phone)
0041 76 445 86 84 (mobile phone)
0041 44 384 26 86 (fax)
H 115 (office room number)
[log in to unmask] (division email)
http://www.dpr.unizh.ch/ (division website)
http://www.juergenhaenggi.ch (private website)
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