Dear SPM users,
I have a question regarding the 4x4 transformation matrices in the header of the MRI data. I use the dicom import function to convert to .nii format and be able to use SPM. My resulting data (ANATOMY.nii) contains a 4x4 transformation matrix (let's say origANAT.mat). When I perform normalization, my wANATOMY.nii also contains a 4x4 matrix (let's say normANAT.mat) and furthermore, a deformation .nii file is generated which contains a comparable matrix (deffield.mat).
I would like to use a 4x4 transformation matrix to normalize my data in a neuronavigation system so I need to know how these matrices relate to each other in order to perform the correct transformation (= normalization) in the neuronav.
I assumed: scannerfiles * origANAT.mat = ANATOMY.nii
ANATOMY.nii * deffield.mat = wANATOMY.nii
origANAT.mat * deffield.mat = normANAT.mat
However, this does not seem to be right if I check this in matlab. Can somebody please help me with this issue?
Thank you very much in advance.
Debby
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