Hi,
I wish to register EPI images to a template. The solution most often used is
this one:
(1) register the EPI image to a high res T1 image (and save the matrix)
(2) register the high res T1 image to the template (and save the matrix)
(3) apply the summed matrices on the EPI image
However, registration-step (1) (EPI -> high res) fails. I am using a Siemens
Vision scanner, with an MPRAGE sequence, and use this to register:
flirt -in EPI -ref MPRAGE -omat epi2mprage.mat
It does produce a matrix without an error message, but the registration is
wrong. The two images are already in the same axial orientation.
Can anyone give a hint why this would fail? Step (2) does work.
Because I wanted to continue, I tried a different solution: SPM comes with an
EPI template. I simply registered the EPI images to this template (this does
work fine, using flirt -in EPI -ref EPI_TEMPLATE -omat epi2template.mat).
Can anyone tell me whether this method is just as valid as the other scheme?
Thanks,
Erik-Jan VLieger
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