I've got myself into some laterality difficulties with negative voxel
dimensions. Let me explain what I did:
1) Using flirt I registered a radiological axial volume to the FSL T1
template. avwhd now reports that this has voxel dimensions of -2,2,2 mm
which is correct I think.
2) I took the registered volume generated in the above step and passed it
through Flirt to generate segmentation maps. avwhd now reports that the
voxel dimensions for the segmented images are 2,2,2 which I don't think is
correct as they should be the same as the input image.
Is the above behaviour expected? It causes me some problems because my
software, mri3dX, assumes that if you overlay one volume on another and
their horizontal voxel dimensions have different signs, then it needs to
flip the laterality of the overlay. In the case of the above, this is
clearly not the case.
All the best,
Dr K.D. Singh
Senior Lecturer and Convenor of the Neuroimaging Research Group,
Director, MRI Research Centre,
Neurosciences Research Institute
Aston University, Birmingham B4 7ET, U.K.
Tel/Fax: +44 (0)121 [204 3865/3864]/[333 4220]
[log in to unmask], http://www.aston.ac.uk/lhs/staff/singhkd/