Dear FSL list,
I am trying to understand how the SENSE factor (on philips scanners)
impacts the way you should unwarp your images. I understand the story
behind unwarping when you actually measure the whole k-plane, but am
confused when you do SENSE encoding.
Should I change soms steps in the unwarping procedure, and if so, which ones?
My guess is that using SENSE will create less distortions in the EPI.
A fewer number of k-lines is read, and therefore one slice takes less
time to measure... and so inhomogeneities in the field will have less
time to create distortions in the phase encode direction. The dwell
time is not altered however... just the number of k-lines you actually
read. The echo spacing is also not altered. But I don't see where or
how this would change the prelude-fugue procedure.
Regards,
Johan
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