Hi Martin,
If I understand you correctly, you have magnitude images with the same distortions. In this case you can use topup on these magnitude images and then apply the correction to the phase images with applytopup.
All the best,
Mark
On 3 Apr 2014, at 13:58, Martin Reiss-Zimmermann <[log in to unmask]> wrote:
> Dear Jesper,
>
> sorry for not explaining in more detail. We are doing research on brain elastography and use a motion-encoding EPI-sequence. The question I had was, whether topup can also be used to remove / reduce the distortions, which can also be found in the phase data. Since the phase data is between -Pi and +Pi, I'm not sure if this works or if influences subsequent phase unwrapping.
> We already tried to optimize our acquisition strategy (low TE, iPAT). For further detail on the technique we are using you can find a similar project from Berlin here: http://www.ncbi.nlm.nih.gov/pubmed/24368262
>
> Best,
> Martin
|