Hi Helen,
ok, I have looked at your data and can confirm there is a problem. I
have tried spm2-style segment, unified segmentation, new segment, and
vbm8, all to no avail. I am pretty sure the problem you see stems from
issues with the initial affine registration step which does not seem to
work well with you data, and the "segmentation results" you see
therefore is based almost entirely on the prior information (that seems
to be why the images are so "pretty", and larger). Sorry for accusing
you to select the wrong images.
Having said that, what does work is the good ole normalization button :)
If you select the EPI template as the target, the normalization of the
input image you sent me works fine as judged by the naked eye.
Conceivably, you could either go with that or try to use the
thus-determined affine mapping to optimize a segmentation approach, but
I would strongly think about whether it may not be an alternative to
using other imaging data for determining the spatial normalization
parameters, if available. May save you time and more trouble :)
Hope this helps,
Marko
Helen Beaumont wrote:
> I'm using SPM* to segment an M0 image with all output in native
> space, tissue probability maps from the tpm directory, and other
> options set to default. The segmented images look OK, but when
> displayed with CheckReg alongside the raw image, they have grown considerably. (See attached).
>> What am I doing wrong?
> Helen Beaumont
> ISBE
> University of Manchester
> Stopford Building, Oxford Rd
> Manchester M13 9PT
> Tel: 0161 275 1259
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____________________________________________________
PD Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
[log in to unmask]
http://www.medizin.uni-tuebingen.de/kinder/epn
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