qsiprep.workflows.fieldmap.phdiff module

Phase-difference B0 estimation

The field inhomogeneity inside the scanner (fieldmap) is proportional to the phase drift between two subsequent GRE sequence.

Fieldmap preprocessing workflow for fieldmap data structure 8.9.1 in BIDS 1.0.0: one phase diff and at least one magnitude image 8.9.2 in BIDS 1.0.0: two phases and at least one magnitude image

qsiprep.workflows.fieldmap.phdiff.init_phdiff_wf(phasetype='phasediff', name='phdiff_wf')

Estimates the fieldmap using a phase-difference image and one or more magnitude images corresponding to two or more GRE acquisitions. The original code was taken from nipype.

(Source code)

Outputs:

outputnode.fmap_ref - The average magnitude image, skull-stripped
outputnode.fmap_mask - The brain mask applied to the fieldmap
outputnode.fmap - The estimated fieldmap in Hz