vtkDICOMImageReader information

Hello,

I wondering where are differences between vtkDICOMImageReader data information and dicom information metadata directly? I see that vtkDICOMImageReader shows different values unless I am mistaken. For example for the tag (0018,0050) I have slice 1mm but DataSpacing: (0.595703, 0.595703, 0.700012) shows me 0.7. The rest seems to be ok. Can somebody explain me or send me the link how I should read information from vtkDICOMImageReader? Thanks in advance.

The slice thickness (0018,0050) and the slice spacing are two different things, they aren’t always equal to each other. See what the DICOM standard has to say about this.

The vtkDICOMImageReader computes the slice spacing as the center-to-center distance between adjacent slices. It’s possible, for example, to have thin slices that are spaced far apart. You aren’t going to find detailed documentation for vtkDICOMImageReader anywhere because this class was written a long time ago and it isn’t maintained anymore. I wrote a newer class called vtkDICOMReader that is part of my vtk-dicom package (on github), which is documented here.

Thank you David for your answer.