Hi everyone,

I’m having some issues converting my DICOMs (DWI) into NIFTI using mri_convert. I looked for other topics with people having the same kind of problem but couldn’t find an answer.

Each time I run mri_convert on my DICOMs I get the following error :
WARNING: file MR.1.3.12.2.1107.5.2.19.45306.2014091812330393354083931 does not contain a Siemens ASCII header
has this file been anonymized?
ERROR: cannot unpack mosiacs without ASCII header

Here are the following DICOMs informations :
Identification
NumarisVer        syngo MR D13
ScannerModel      Skyra 
PatientName       xxxxx
Date and time
StudyDate         20140918
StudyTime         121037.203000 
SeriesTime        123450.600000 
AcqTime           123257.367500 
Acquisition parameters
PulseSeq          ep_b0 
Protocol          AX DTI no angle MS NEX 4 2
PhEncDir          COL
EchoNo            1
FlipAngle         90
EchoTime          96
InversionTime     -1
RepetitionTime    4700
PhEncFOV          0
ReadoutFOV        0
Image information
RunNo             4
SeriesNo          5
ImageNo           1
NImageRows        990
NImageCols        990
NFrames           64
SliceArraylSize   0
IsMosaic          1
ImgPos            1075.1575 1069.8385 -48.6769 
VolRes              2.1818   2.1818   2.0000 
VolDim              0        0        0 
Vc                 -1.0000  -0.0000   0.0000 
Vr                 -0.0000  -1.0000   0.0000 
Vs                  0.0000   0.0000   0.0000 
VolCenter           0.0000   0.0000   0.0000 
TransferSyntaxUID 1.2.840.10008.1.2.1


Then I try using mri_convert -it dicom, it converts the files but not as it is expected, you could notice the difference when I run mri_info on my output :
Volume information for output.nii.gz
          type: nii
    dimensions: 990 x 990 x 1 x 64
   voxel sizes: 2.1818, 2.1818, 2.0000
          type: SHORT (4)
           fov: 2160.000
           dof: 0
        xstart: -1080.0, xend: 1080.0
        ystart: -1080.0, yend: 1080.0
        zstart: -1.0, zend: 1.0
            TR: 4700.00 msec, TE: 0.00 msec, TI: 0.00 msec, flip angle: 0.00 degrees
       nframes: 64
       PhEncDir: UNKNOWN
ras xform present
    xform info: x_r =  -1.0000, y_r =  -0.0000, z_r =  -0.0000, c_r =    -4.8425
              : x_a =  -0.0000, y_a =  -1.0000, z_a =  -0.0000, c_a =   -10.1615
              : x_s =   0.0000, y_s =   0.0000, z_s =   1.0000, c_s =   -47.6769
Orientation   : LPS
Primary Slice Direction: axial

voxel to ras transform:
               -2.1818  -0.0000  -0.0000  1075.1575
               -0.0000  -2.1818  -0.0000  1069.8385
                0.0000   0.0000   2.0000   -48.6769
                0.0000   0.0000   0.0000     1.0000

voxel-to-ras determinant 9.52066

ras to voxel transform:
               -0.4583   0.0000   0.0000   492.7805
                0.0000  -0.4583   0.0000   490.3426
               -0.0000  -0.0000   0.5000    24.3384
                0.0000   0.0000   0.0000     1.0000

I would really appreciate your help, thank you.

Best,

Ismail