That looks good regarding setting up a standard field map.  I would recommend 
setting the SBRef if it is available.  I would recommend not smoothing the data 
more than the voxel resolution (can always do more later if you have to).  I 
would recommend using MSMSulc instead of FS as MSMSulc produces better 
functional alignment and less distortion relative to FreeSurfer.  You can get 
the MSM binary here: https://github.com/ecr05/MSM_HOCR/releases

In general we prefer the spin echo field maps because you can use them for bias 
correction too and some of the internal registrations are better conditioned, 
but regular field maps produce acceptable distortion correction.

Peace,

Matt.

From: 
<[email protected]<mailto:[email protected]>>
 on behalf of zhou y <[email protected]<mailto:[email protected]>>
Date: Tuesday, June 5, 2018 at 11:48 AM
To: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
Subject: [HCP-Users] Applying field map from a double-echo gradient echo 
sequence to the GeneralfMRI Processing Pipeline

Dear Sir/Madam,

I am applying our lab's local 3T MRI data to the hcp minimal preprocessing 
pipelines. Since we used a field map from a double-echo gradient echo sequence 
different from HCP data which used the opposite phase encoded EPIs, I would 
like to check whether I have set the following parameters approriately with 
gradient distortion correction and later processing.

    UnwarpDir=`echo $PhaseEncodinglist | cut -d " " -f $i`
    
fMRITimeSeries="${StudyFolder}/${Subject}/unprocessed/3T/${fMRIName}/${Subject}_3T_${fMRIName}.nii.gz"
   fMRISBRef="NONE"
    DwellTime="0.00049"   #    EchoSpacing="0.00049"
    DistortionCorrection="SiemensFieldMap" # we used Siemens for scanning
    BiasCorrection="NONE"
    SpinEchoPhaseEncodeNegative="NONE" # using regular FIELDMAP
    SpinEchoPhaseEncodePositive="NONE" #using regular FIELDMAP
    
MagnitudeInputName="${StudyFolder}/${Subject}/unprocessed/3T/${fMRIName}/${Subject}_3T_FieldMap_merg.nii.gz"
 # 4D Magnitude volume with two 3D timepoints, we merged the fieldmap_long and 
fieldmap_short into one 4D file
    
PhaseInputName="${StudyFolder}/${Subject}/unprocessed/3T/${fMRIName}/${Subject}_3T_FieldMap_phase.nii.gz"
   # using fieldmap_phase file

    GEB0InputName="NONE"
    DeltaTE="2.46"
    FinalFMRIResolution="2"
      # GradientDistortionCoeffs="${HCPPIPEDIR_Config}/coeff_SC72C_Skyra.grad"
    
GradientDistortionCoeffs="/home/Projects/HCP_MINPre/Pipelines/global/config/coeff.grad"
 #from the scanning center with Siemens
    TopUpConfig="NONE" #using regular FIELDMAP
    TopUpConfig="NONE" #using regular FIELDMAP

    MCType="MCFLIRT"

-----------------------------------------------------

    LowResMesh="32"
    FinalfMRIResolution="2"
    SmoothingFWHM="4"
    GrayordinatesResolution="2"
    # RegName="MSMSulc" #MSMSulc is recommended, if binary is not available use 
FS (FreeSurfer)
    RegName="FS"

-----------------------------------------------------

Actually I have tested some subjects to run these pipelines without any error 
reported. Yet I am still not sure whether I have set every parameter right or 
not. And how do I check the results?

Best,
   Zoey



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