I need the clarification of analyze 7.5 format in sagittal flipped case. I just found that it is different from the one I used for freesurfer. I used Graham version from his web site:

wideman-one.com/gw/brain/analyze/formatdoc.htm has

*hist.orient* *Mayo name* *Voxel[Index0, Index1, Index2] * *Index0* *Index1* *Index2* 0 (default) transverse unflipped R-L P-A I-S 1 coronal unflipped R-L I-S P-A 2 sagittal unflipped P-A I-S R-L 3 transverse flipped R-L A-P I-S 4 coronal flipped R-L S-I P-A 5 sagittal flipped P-A S-I R-L Note: Index0 is fastest-varying (innermost-nested) index, Index2 the outermost. Index0..Index2 are often called X, Y, Z, but I am trying to avoid confusion with spatial coordinates.

I found that http://nifti.nimh.nih.gov/dfwg/nifti_revised.html has

* /vs./ qform_code*: The ANALYZE-7.5 format indicated 3D orientation with the 1 byte code orient, which was to be interpreted as

0 = transverse-unflipped R?L P?A I?S 1 = coronal-unflipped R?L I?S P?A 2 = sagittal-unflipped P?A I?S R?L 3 = transverse-flipped R?L A?P I?S 4 = coronal-flipped R?L S?I P?A 5 = sagittal-flipped P?A I?S L?R

Note that the second and third axis of "sagittal flipped" are flipped ;-)

Tosa