Dear SPM users,
I am trying to normalize my Tc-ECD SPECT data from PD patients and elderly
control subjects to the SPECT template using SPM2. Using the defaults
(except of the bounding box which I have changed to template) resulted in
poor normalization between the subjects images to the SPECT template.
Assuming that the patients and control subjects brains are smaller than the
template (due to atrophy caused by the disease and age), I have looked for
something which will correct the size differences. When I set the defaults to:
weight template with default brain mask and weight source with affine
transformation without cutoff (at the parameter estimation defaults) it worked
well. I wanted to know if it makes sense because I couldn't find any reference
for it, although it is mentioned in the help section that weighting may be used
for lesioned brains and then the normalization is done according to the brain
shape rather than the head shape.
Any advice will be appreciated,
Thank you,
Yafit
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