Possible compatibility bug with fsleyes?

[mbl...@gmail.com]

Dear Gary and DTI-TK community,

For our last work, I've been using DTI-TK to create a neonatal template (see here for the details). The obtained registrations and templates were excellent!

However, I've encountered a serious issue when converting the DTI-TK template to FSL (for viewing purposes). I converted the template to FSL using the following command: 

TVEigenSystem -in tensor.nii.gz -type FSL  

When I open the result image in fslview (V1 overlaid to L1) everything looks great:

https://ibb.co/4T2htvV

https://ibb.co/sqSWz89

(This has been resized for visualization purposes)

Recently we uploaded the  FSL version and the problem comes when I open he same images in fsleyes:

https://ibb.co/sszZcZx

https://ibb.co/CHJBrYT

As you can see, there is a flipping in the vectors. Is this a known bug? Is it just a visualization issue?

Thanks in advance.

Best regards,

Manuel

[mbl...@gmail.com]

Hi,

Just as a follow up to this, I found the solution here: https://users.fmrib.ox.ac.uk/~paulmc/fsleyes/userdoc/latest/troubleshooting.html#line-vectors-tensors-fibre-orientation-distributions-are-left-right-flipped

Sorry for the inconvenience.

Best regards,

Manuel

[Chris Parker]

Thanks Manuel. I was just looking into it this morning and came to the same conclusion.

It looks like fsleyes turns on the L/R flip for the DTI-TK tensor images converted to FSL format, even though it's not needed. 

We can just turn off the L/R flip in this case.

Best,

Chris