Mark,
Yes, I say fieldmaps because this happened to quite a few different
acquisitions.
So yeah, the problem is that the PE direction is not consistent between the
phase maps. I figured there was nothing that could be done to correct this,
but just wanted to make sure.
Thanks for the help,
Carlos
On Fri, 1 Aug 2008 18:06:58 +0100, Mark Jenkinson <[log in to unmask]> wrote:
>Maybe what you are saying is that the two different
>echoes within what I would call one single fieldmap
>are different. Is that right? I have assumed that you
>have been talking about two completely separate
>fieldmap acquisitions (given that you talk about
>fieldmap*s* and not just one fieldmap), and that the
>individual echo images that go into each fieldmap were
>internally consistent. If you have the case where they are
>not internally consistent with respect to PE direction,
>then I'm afraid there is nothing you can do as the phase
>subtraction will leave you with residual phase that
>is artefactual.
>
>Please let me know what the exact situation is.
>
>All the best,
> Mark
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