Dear all,

I have a question about convert Dicom data to NIfTI format. I tried xmedcon, MRIConvert, and dcm2nii, but the results are not identical. The data matrices are the same, but the MNI coordinates are different from each other. For instance, in data matrices X=40, Y=34, Z=20, the values are all 927 for three methods. But the MNI coordinates are 24x3x16 for xmedcon, 25x0x18 for MRIConvert, and 25x3x19 for dcm2nii. I also checked the affine parameters of reorient of these three methods, and they are different.
 
For xmedcon:
[3.4375 0 0 -110;
0 3.4375 0 -110;
0 0 4 -60]
 
for MRIConvert:
[3.4375 0 0 -109.48277;
0 3.215655 -1.4136 -79.2246;
0 1.214895 3.7416 -93.2032]

and for dcm2nii:
[3.4375 0 0 -109.48278;
0 3.215589 -1.413899 -76.013977;
0 1.215070 3.741776 -91.996414];

Does anyone have an idea of these differences? I thought the programs should get same information for the Dicom data. But since they are different, which one should I use?

Any suggestion would be greatly appreciated!

Thanks,
Sheng