Extracting PA and AP from dicom

The sequences are labelled fieldmap (see further info below).

If these aren’t suitable for relatively easy plugging into mrtrix, is there an easier way to get things to work from the nii.gz and .bvals that I have instead?

Thank you again!

mrinfo for first fieldmap:

mrinfo: [100%] reading DICOM series "gre_field_mapping"
************************************************
Image name:          "[MR] gre_field_mapping"
************************************************
  Dimensions:        64 x 64 x 55 x 2
  Voxel size:        3 x 3 x 3 x ?
  Data strides:      [ -1 -2 3 4 ]
  Format:            DICOM
  Data type:         unsigned 16 bit integer (little endian)
  Intensity scaling: offset = 0, multiplier = 1
  Transform:                    1   2.051e-10  -7.272e-18         -93
                       -2.023e-10      0.9866     -0.1633      -82.62
                        -3.35e-11      0.1633      0.9866      -86.23
  EchoTime:          0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492,0.00738,0.00492
  FlipAngle:         60
  MultibandAccelerationFactor: 1
  PhaseEncodingDirection: i-
  PixelBandwidth:    260
  RepetitionTime:    0.688
  SliceEncodingDirection: k
  SliceTiming:       0,1.04250002,0.704999983,0.362500012,0.717499971,0.375,0.0375000015,1.08000004,0.0500000007,1.09500003,0.0625,0.412499994,0.075000003,1.12,0.779999971,0.4375,0.100000001,1.14499998,0.805000007,0.462500006,0.817499995,1.16999996,0.137500003,0.487500012,0.842499971,1.19500005,0.855000019,0.512499988,0.867500007,0.524999976,0.1875,1.23249996,0.892499983,0.550000012,0.212500006,0.5625,0.917500019,0.577499986,0.237499997,1.28250003,0.942499995,0.602500021,0.954999983,0.61500001,0.967499971,0.627499998,0.287499994,1.33249998,0.992500007,1.34500003,1.005,1.35749996,1.01750004,0.67750001,1.02999997

mrinfo for second fieldmap:

mrinfo: [100%] reading DICOM series "gre_field_mapping"
************************************************
Image name:          "[MR] gre_field_mapping"
************************************************
  Dimensions:        64 x 64 x 55
  Voxel size:        3 x 3 x 3
  Data strides:      [ -1 -2 3 ]
  Format:            DICOM
  Data type:         unsigned 16 bit integer (little endian)
  Intensity scaling: offset = -4096, multiplier = 2
  Transform:                    1   2.051e-10  -7.272e-18         -93
                       -2.023e-10      0.9866     -0.1633      -82.62
                        -3.35e-11      0.1633      0.9866      -86.23
  EchoTime:          0.00738
  FlipAngle:         60
  MultibandAccelerationFactor: 1
  PhaseEncodingDirection: i-
  PixelBandwidth:    260
  RepetitionTime:    0.688
  SliceEncodingDirection: k
  SliceTiming:       0,0.349999994,0.0125000002,0.362500012,0.0250000004,0.375,0.0375000015,0.387499988,0.0500000007,0.402500004,0.0625,0.414999992,0.075000003,0.42750001,0.0874999985,0.439999998,0.100000001,0.452499986,0.112499997,0.465000004,0.125,0.477499992,0.137500003,0.49000001,0.150000006,0.502499998,0.162499994,0.514999986,0.174999997,0.527499974,0.1875,0.540000021,0.200000003,0.55250001,0.212500006,0.564999998,0.224999994,0.577499986,0.237499997,0.589999974,0.25,0.602500021,0.262499988,0.61500001,0.275000006,0.627499998,0.287499994,0.639999986,0.300000012,0.652499974,0.3125,0.665000021,0.324999988,0.67750001,0.337500006