Hi all,
For non-human segmenters, yesterday I confirmed that if you segment from
a volume whose voxdims are not cubic 1mm, Caret generates a surface
whose mm coordinates are accurate (assuming the voxdims are accurate).
Example: With a cubic 0.5mm anatomical volume loaded in window 1 and
the resulting fiducial surface in window 2, click in volume window on
voxel along medial surface; then click on voxel 57 slices laterally
(keeping coronal and axial slices constant). Fiducial distance is 28.3
(roughly half of 57):
VOXEL IJK(1, 86, 41) XYZ(0.0, -5.0, 0.0)
View Window 2 Fiducial XYZ: -0.1, -5.3, 0.8
VOXEL IJK(58, 86, 41) XYZ(28.5, -5.0, 0.0)
View Window 2 Fiducial XYZ: 28.2, -5.5, 0.2 Distance: 28.3
Most of you probably took this for granted, but in the old SureFit days,
this wasn't true (unless you explicitly scaled the surface in Caret).
It has probably been true in Caret since segmentation was added, but
Caret used to prevent you from segmenting if voxdims were not cubic
1mm. John made a change a while back to enable non-human segmenters to
avoid lying to Caret.
Donna
