Re: FA measured from Regions -stat and Tracts -Stat

[Khan Hekmatyar]

Hi Frank

Good morning, One quick question, The FA measured from two different statistics were different, why it is so?

Why the FA from region (ROI) stat is lower than FA from tract statistics?

FA of the roi is from ROI only ? or FA of the tracts from entire tracts (even outside the seed region). Just confused

Thanks

Khan

 

[Frank Yeh]

ROI only average voxel-wise FA value.

Tract-based FA first estimates FA at subvoxel resolution using interpolation.

The results will be different but should be mostly consistent because
the differences are due to interpolation.

Best regards,
Frank

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[Khan Hekmatyar]

Thanks, 

where do I get information about the diffusion metrics? 

the link is broken

https://sites.google.com/a/labsolver.org/dsi-studio/Manual/diffusion-mri-indices

Ned

[Frank Yeh]

https://dsi-studio.labsolver.org/doc/how_to_interpret_dmri.html

[Khan Hekmatyar]

I mean the shape metrics in this page

https://dsi-studio.labsolver.org/doc/gui_t3_atk.html

On Saturday, January 24, 2026 at 2:29:19 PM UTC-5 Frank Yeh wrote:

[Frank Yeh]

https://www.sciencedirect.com/science/article/pii/S1053811920308156

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[Khan Hekmatyar]

Thank you very much, Which dii_fa should we use to report? interpolated or voxel wise dti_fa? For example my voxel wise FA is quite different, (0.11 for ROI voxelwise, 0.22 for track FA)
Ned

[Frank Yeh]

It depends on the study and there is no absolutely correct answer.

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[Khan Hekmatyar]

ok. what we do is mice brain analysis, before and after the treatment,

[Frank Yeh]

I would suggest checking out other mice studies and see how they
reported the results.

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[Khan Hekmatyar]

Thank you , I will take a look. 

Kahn