Dear SPM community,
I have several questions regarding my analysis using SPM99, in
particular coregistration.
I am trying to perform a group comparison (20 normal controls +
48 AD patients) in the hope of comparing SPM with some dedicated
software attached to our gamma camera. The images have
all been registered to an inhouse template by the other software.
Subsequently I have loaded the registered images into SPM99 and
performed some Gaussian smoothing. The next thing required was to
give the results some spatial meaning, so I wanted to
perform an identical rigid body transformation to the SPM99 SPECT
template on each image, then perform the group statistics
accordingly.
The method I adopted was as follows:
I created a mean image from both the controls and patients, then
using the Coregistration facility in SPM99 with the Coregister Only
option, coregistered the object (mean) image to the target (SPECT
Template) image and consequently found the transformation
matrix. I then applied this matrix to each and every image volume
in my analysis..................I think?
As I'm not doing any reslicing, are the newly created transformed
image sets simply replacing the original image data sets, or
have I completely misinterpreted the purpose of coregistration?
I just want to ensure that my original image volumes have all
been transformed to the SPECT Template using the same
transformation matrix throughout and to preserve both voxel size
and counts.
Can anybody put me straight with this. Am I doing this correctly,
or am I way off!
Any help is greatly appreciated.
Cheers
Sean Colloby
Research Associate (SPM beginner)
Wolfson Research Centre
Newcastle General Hospital
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