Re: [Freesurfer] Partial volume correction for aseg.mgz files

2019-03-29 Thread Bruce Fischl

Hi Da-Yea

you would need to compute the jacobian of the warping and apply it at 
each voxel to scale the volumes (accounting for the warping).


cheers
Bruce
On Fri, 29 Mar 
2019, Song, Da-Yea wrote:




External Email - Use Caution

Hello,

 

I’m trying to extract regions (mri_extract_label) of interest from the aseg.mgz 
files and compare
them to our manual segmentations. I’ve warped these ROI masks onto our native 
space. I’ve noticed on
the forum that there were mentions of discrepancies in the volumes from 
aseg.mgz and aseg.stats due
to partial volume correction. If I were to calculate the volume using the ROI 
extracted masks (that
have been warped on to the native space), how can I calculate for partial 
volume correction? Any
suggestions would be greatly appreciated!

 

Thank you,

Da-Yea


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[Freesurfer] Partial volume correction for aseg.mgz files

2019-03-29 Thread Song, Da-Yea
External Email - Use Caution

Hello,

I'm trying to extract regions (mri_extract_label) of interest from the aseg.mgz 
files and compare them to our manual segmentations. I've warped these ROI masks 
onto our native space. I've noticed on the forum that there were mentions of 
discrepancies in the volumes from aseg.mgz and aseg.stats due to partial volume 
correction. If I were to calculate the volume using the ROI extracted masks 
(that have been warped on to the native space), how can I calculate for partial 
volume correction? Any suggestions would be greatly appreciated!

Thank you,
Da-Yea

--
Disclaimer:


The materials in this e-mail are private and may contain Protected Information. 
Please note that e-mail communication is not encrypted by default. You have the 
right to request further emails be encrypted by notifying the sender. Your 
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recipient, be advised that any unauthorized use, disclosure, copying, 
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information is strictly prohibited. If you have received this e-mail in error, 
please immediately notify the sender via telephone or return e-mail.
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