Reading correct orientations of Analyze 7.5 data into 3D Slicer

Problem report for Slicer 5.0.2 win-amd64: [please describe expected and actual behavior]

When loading an axial Analyze 7.5 dataset (*.img, *.hdr), anterior/posterior directions are incorrectly flipped. I know documentation says “Image orientation is specified ambiguously in this format, therefore its use is strongly discouraged,” however this is a fairly easy fix for what is likely the most common orientation. Can a patch be drafted or is there some global import setting I am overlooking?


I highly suspect anyone would spend any time to create a patch for such old format.

If you are certain the flip is in A/P axis, you can create a transform matrix in which the third diagonal element is -1, assign your volume to it, harden the transform (right click in the data) and save it as nrrd.

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