Echo fieldmaps for EPI field map distortions -Rookie question

I am using a pipeline for a resting state analysis and I want to perform a fieldmap correction. I am supposed to provide the pipeline with two magnitude images and a phase difference image, however our Siemens scanner only recorded two magnitude images in two phase directions (fieldmap_AP and fieldmap_PA). How do I get my phasediff image? Is there a way to get that?

Hi @Reubebe,

It sounds like you acquired a different kind of fieldmap. The fact that your images have different directions suggest you acquired a set of reverse phase encoded images (I.e., blip up blip down). You can use these for distortion correction as it.

Best,
Steven

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