HBN Site-SI MRI data:: BIDS validation:: Error code 15 - ECHO_TIME1-2_NOT_DEFINED

Dear humans!
I am running BIDS validation on Healthy Brain Network (HBN) MRI data.

Data from site ‘SI’ structured as:

fmap/
sub-[_ses-][_acq-][_run-]_phasediff.nii[.gz]
sub-[_ses-][_acq-][_run-]_phasediff.json
sub-[_ses-][_acq-][_run-]_magnitude1.nii[.gz]
sub-[_ses-][_acq-][_run-]_magnitude2.nii[.gz]
sub-[_ses-][_acq-][_run-]_magnitude1.json
sub-[_ses-][_acq-][_run-]_magnitude2json

throws an error for _phasediff.json files:

[ERR] You have to define ‘EchoTime1’ and ‘EchoTime2’ for this file. (code: 15 - ECHO_TIME1-2_NOT_DEFINED)

Here’s _phasediff.json example content:

{
    "InPlanePhaseEncodingDirectionDICOM": "COL", 
    "ProcedureStepDescription": "CMI_HBN", 
    "DeviceSerialNumber": "26121", 
    "AcquisitionMatrixPE": 64, 
    "ImageOrientationPatientDICOM": [
        1, 
        0, 
        0, 
        0, 
        1, 
        0
    ], 
    "ManufacturersModelName": "Avanto", 
    "ProtocolName": "Field_Map", 
    "RepetitionTime": 0.492, 
    "MagneticFieldStrength": 1.5, 
    "PhaseEncodingSteps": 64, 
    "MRAcquisitionType": "2D", 
    "SliceThickness": 3, 
    "DwellTime": 3e-05, 
    "TxRefAmp": 236.302, 
    "PixelBandwidth": 260, 
    "SAR": 0.360405, 
    "ConversionSoftware": "dcm2niix", 
    "ScanningSequence": "GR", 
    "Manufacturer": "Siemens", 
    "PercentPhaseFOV": 100, 
    "ReconMatrixPE": 64, 
    "FlipAngle": 90, 
    "SeriesDescription": "Field_Map", 
    "PartialFourier": 1, 
    "ConversionSoftwareVersion": "v1.0.20171204 (OpenJPEG build) GCC4.8.4", 
    "ShimSetting": [
        124, 
        -198, 
        437, 
        1256, 
        257, 
        550, 
        668, 
        346
    ], 
    "PulseSequenceDetails": "%SiemensSeq%_gre_field_mapping", 
    "PatientPosition": "HFS", 
    "SequenceName": "_fm2d2r", 
    "ReceiveCoilName": "32Ch_Head", 
    "SpacingBetweenSlices": 3, 
    "ImageType": [
        "ORIGINAL", 
        "PRIMARY", 
        "P", 
        "ND"
    ], 
    "EchoTime": 0.00804, 
    "SequenceVariant": "SP", 
    "PhaseResolution": 1, 
    "BaseResolution": 64, 
    "PhaseEncodingDirection": "j-", 
    "SoftwareVersions": "syngo_MR_B17", 
    "StationName": "MRC26121", 
    "Modality": "MR", 
    "EchoNumber": 2
}

EchoTime in _magnitude1.json =0.00328 ,and in _magnitude2.json = 0.00804

According to the BIDS website:

Does this mean that for _phasediff.json EchoTime1=0.00328 and EchoTime2= 0.00804?

Hi @neuroLena,

Yes

Best,
Steven

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