Hi there,
> Hi. I have downloaded some MRI images from ADNI database. When I use SPM
> or MRIcro, I can view Axial, Coronal and Sagittal view of these images.
This is probably because they are in 3D-format, i.e. consist of several
slices.
> The dimensions of these images are 192*160*192 which means I have
> acquired for example 192 axial images each of 160*192 dimension.
No, it means you have 192 axial slices in each image, with 160x192
voxels in each slice. They all together make up the 3D volume of the
whole image.
> When I perform a two sample t-test, does SPM use just axial images to
> perform between group comparisons? If so then how can MIPs with coronal
> and sagittal views are produced?
No, you need several images with 3 dimensions each which can then be
compared voxel-wise after they have been transformed into a standard space.
> Excuse me if the questions where stupid. These questions aroused when I
> read “Comparison of standard and optimized voxel-based morphometry for
> analysis of brain changes associated with temporal lobe epilepsy” in
> which 124 coronal T1-weighted images were used and at last MIPs with
> different views were produced.
I need to read this paper again as it obviously is less clear than we
had intended :) We used 124 3D-datasets which were acquired in the
coronal orientation. Being 3D, however, this does not make much of a
difference (except for some artifacts in sensitive regions hopefully
being less prominent).
You may want to read "Voxel based morphometry - the methods" and get
acquainted with the steps involved. After that, slowly approach the
famous/infamous Good et al paper on normal ageing (and then be happy
because all this iterative processing is not necessary anymore in spm5 :)
> Thanks.
Sure.
> Do you Yahoo!?
No :)
Hope this helps,
Marko
--
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Marko Wilke (Dr.med./M.D.)
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Universitäts-Kinderklinik University Children's Hospital
Abt. III (Neuropädiatrie) Dept. III (Pediatric neurology)
Hoppe-Seyler-Str. 1, D - 72076 Tübingen
Tel.: (+49) 07071 29-83416 Fax: (+49) 07071 29-5473
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