[Freesurfer] Coordinates transformation from conformed space to the original FLAIR image

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Hi everyone,

I have used both T1 and (T2) Flair images as inputs to recon-all, and I have generated some coordinates (ROI) that I can transform to the original T1 images. Basically, I use the two matrixes obtained from the mri_info -- vox2ras commands:

Sr = mri_info --vox2ras $SUBJECTS_DIR/$subject/mri/orig/001.mgz Sc = mri_info --vox2ras $SUBJECTS_DIR/$subject/mri/T1.mgz

For a given point Coordinate=(x, y, z, 1) in the conformed space, I get the coordinates in the original T1 space using the formula:

t1_Coordinate = inv(Sr) * Sc * Coordinate.

The above formula works fine. But I also want to get the transformed coordinates in the Flair image space. I have used a similar way:

Srf = mri_info --vox2ras $SUBJECTS_DIR/$subject/mri/orig/FLAIRraw.mgz Sc = mri_info --vox2ras $SUBJECTS_DIR/$subject/mri/T1.mgz flair_Coordinate = inv(Srf) * Sc * Coordinate.

But the above calculation is not correct. Does anyone have an idea of how to get this flair coordinate?

Thank you!!!

Xiaojiang