Where is Fieldmap related information in .json file?

1 
{
    "Manufacturer": "Philips",
    "PatientPosition": "HFS",
    "SeriesDescription": "ImageMRSERIES",
    "ProtocolName": "AxialfMRI_rest",
    "SeriesNumber": 3,
    "AcquisitionNumber": 3,
    "ImageComments": "RESEARCHMRI",
    "PhilipsRescaleSlope": 0.79707,
    "PhilipsRescaleIntercept": 0,
    "PhilipsScaleSlope": 0.0392726,
    "UsePhilipsFloatNotDisplayScaling": 1,
    "EchoTime": 0.035,
    "RepetitionTime": 3,
    "SliceTiming":[2.914285714285714,
 2.742857142857143,
 2.5714285714285716,
 2.4,
 2.2285714285714286,
 2.057142857142857,
 1.8857142857142857,
 1.7142857142857144,
 1.542857142857143,
 1.3714285714285714,
 1.2,
 1.0285714285714285,
 0.8571428571428572,
 0.6857142857142857,
 0.5142857142857142,
 0.34285714285714286,
 0.17142857142857143,
 0.0,
 2.8285714285714287,
 2.657142857142857,
 2.4857142857142858,
 2.3142857142857145,
 2.142857142857143,
 1.9714285714285715,
 1.8,
 1.6285714285714286,
 1.457142857142857,
 1.2857142857142858,
 1.1142857142857143,
 0.9428571428571428,
 0.7714285714285715,
 0.6,
 0.4285714285714286,
 0.2571428571428571,
 0.08571428571428572],
    "ImageOrientationPatientDICOM": [
        0.99894,
        0.0242216,
        0.0391317,
        -0.0261582,
        0.998419,
        0.0497599
    ],
    "ConversionSoftware": "dcm2niix",
    "ConversionSoftwareVersion": "v1.0.20220505",
    "TaskName": "rest"
}

Above is my .json file.

I’m trying to run fMRIprep but I’m not sure whether if I have field map information or not.

As far as I know, if I don’t have field map info, --use-syn-sdc will automatically use t1w images as reference image to preform SDC for epi image.(Please tell me if I’m wrong)

It seems like many people in NeuroStars have PhaseEncodingDirection in their .json file.

But sadly, I don’t.

If I want to perform SDC, should I just add --use-syn-sdc in my command? or Am I missing field map information?

Any suggestions would be appreciated.

Best,
dhwnsdyd21.

2

Hi @dhwnsdyd21,

Based on the presence of TaskName in your JSON, it looks like you posted your BOLD json. In either case, phase encoding direction would be needed if working with pepolar fieldmaps (two reverse phase encoded images), but not necessarily for magnitude-phasediff images. But, total readout time is required. Unfortunately Phillips does not export a lot of this information by default so you can default the scanner protocol or your MRI technician for help on this.

Best,
Steven