Dear All,
I am part of a team that has been looking at structural changes in the
brain following a clinical trial of typical antipsychotics for patients with
schizophrenia. We have at our disposal contiguous, interleaved dual-echo
fast spin-echo proton-density, T1, T2 and SPGR images of the whole brain for
a total of 45 patients (though for 17 we have only baseline images).
We would like to conduct a VBM analysis using SPM2 or SPM5, and given their
higher resolution, are considering using the 3D T1 images instead of the 2D
images. My question is whether there is any reason not to use 3D images for
this purpose. I have scanned the literature, but have not found much
information on the relative advantages/disadvantages of using 3D images for
VBM. I would also be interested in finding out whether there is any
advantage in using axial versus coronal images in VBM (our 3D images are in
coronal orientation, whereas the 2D images are in axial orientation).
Thank you,
Jonathan Ipser
Department of Psychiatry and Mental Health
University of Cape Town
----------Imaging specifications provided below (all images scanned at
1.5Tesla):
3D T1-images
Slice thickness:1.5mm
TR=1900ms
TE=3.93ms
Flip angle=15 degrees
X:0.43mm; Y:0.43mm; Z:1.5mm
2D images (T1, T2 & PD)
Slice thickness:2.5mm
TR=4000ms
TE=89ms
Flip angle=150 degrees
X: 0.43mm; Y: 0.43mm; Z: 2.75mm
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