Dear Fielmap experts,
Sorry if I post naive questions but I could not find the answer in the
archives...
I'm currently working with DTI images and wonder wether I could apply
the field map corrections to DTI images.
More specifically:
1/ we acquire our images with spin-echo EPI: is the Fieldmap method,
firstly designed to handle gradient-echo EPIs, able to handle this kind
of SE-sequence?
2/ Does it sound really bad to apply the unwarping *without* the
estimated movement-by-distorsion implemented in the Realign and Unwrap
toolbox? This is because the estimated motion is strongly correlated to
the diffusion direction we applied for each image, perhaps even after a
Eddy-current distorsions correction (that is correction of the
distorsions due to the diffusion gradients with a method like
http://brainvisa.info/pdf/mangin-MIA02.pdf).
By the way, for those interested, I wrote a simple SPM2 program to apply
a VDM computed with the Fieldmap toolbox to a serie of images *without*
performing any other realignment (as done in realign and unwrap)? In
other word, the program allows to apply the "write unwrapped" button of
the FieldMap Toolbox but for multiple images (avoiding hundreds loads
and clicks!!!).
Thank you very much in advance for your help,
Nicolas.
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