hello all,
after reading the notes at http://www.fmrib.ox.ac.uk/fslfaq/LRfaq.html, i have a question about
the statement:
> The FSL utility fslview displays the images in radiological convention.
how does fslview determine Left/Right in order to display the volume in radiological convention?
i ask this question because i am unable to register a volume to the supplied standard volume via
FEAT/FLIRT Registration. i know the problem is because my data is not in the same orientation as
the standard volume. but i cannot figure out why my data is interpreted as being in the wrong
orientation when other volumes i have are interpreted correctly. i checked the .hdr fields one-by-
one and i can see no obvious reason for the interpretation differences.
details:
VolumeA registers successfully.
VolumeB does not register.
i open VolumeA, VolumeB, and standard/avg152T1_brain in MEDx with a file format of "Raw
Generic". i did this as a way to bypass any information that might be supplied by the .hdr file, ie,
there is no indication of Right/Left. i then define the volumes' characteristics in the [Options...]
dialog box. VolumeA and VolumeB, loaded as "Raw Generic", have the same orientation;
standard/avg152T1_brain is in a different orientation (a 180 degree rotation around the z-axis).
yet VolumeA registers successfully with standard/avg152T1_brain via FLIRT but VolumeB does
not.
VolumeA and VolumeB are created from two different programs. i am trying to reconcile the
differences. i've changed fields in the .hdr file one at a time to see if i can get the FLIRT
registration with VolumeB to be successful. so far i have not found the magic .hdr field -- if there
is one.
is my conclusion that FLIRT somehow determines Left/Right (from the .hdr file?) correct? if so,
how? what field does it use if it uses a .hdr field at all?
thanks,
- bettyann
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