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Dear,
I would like to know how the eTIV is estimated in SynthSeg and SynthSeg+ . Is it a combination of CSF+ventricles+WM+GM masks? Or do you estimate is using the registration to MNI space approach?
Best, Marco
The former!
-- Juan Eugenio Iglesias http://www.jeiglesias.com
From: Marco Ganzetti marco.ganzetti@biogen.com Date: Monday, June 30, 2025 at 05:57 To: freesurfer@nmr.mgh.harvard.edu freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] eTIV in SynthSeg
External Email - Use Caution Dear,
I would like to know how the eTIV is estimated in SynthSeg and SynthSeg+ . Is it a combination of CSF+ventricles+WM+GM masks? Or do you estimate is using the registration to MNI space approach?
Best, Marco
External Email - Use Caution
Thanks. In SynthSeg, if I set a threshold at 0.5 on the segmentation output, should I get exactly the TIV? Label 0 is the background, therefore all the labels above 0 should constitute the TIV. Is this the case?
Best, Marco
From: Iglesias Gonzalez, Juan E. JIGLESIASGONZALEZ@mgh.harvard.edu Date: Tuesday, 1 July 2025 at 05:51 To: Freesurfer support list freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] Re: eTIV in SynthSeg EXTERNAL SENDER The former!
-- Juan Eugenio Iglesias http://secure-web.cisco.com/1UogwMeus6BE-_6ObueYjbFjrZdTcPcVKFrL-tZvlS-tEYy2...
From: Marco Ganzetti marco.ganzetti@biogen.com Date: Monday, June 30, 2025 at 05:57 To: freesurfer@nmr.mgh.harvard.edu freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] eTIV in SynthSeg
External Email - Use Caution Dear,
I would like to know how the eTIV is estimated in SynthSeg and SynthSeg+ . Is it a combination of CSF+ventricles+WM+GM masks? Or do you estimate is using the registration to MNI space approach?
Best, Marco
Not exactly because volumes are computed from soft segmentations rather than discrete labels, but yeah, it should be very close.
-- Juan Eugenio Iglesias http://www.jeiglesias.com
From: Marco Ganzetti marco.ganzetti@biogen.com Date: Tuesday, July 1, 2025 at 3:55 AM To: Freesurfer support list freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] Re: eTIV in SynthSeg
External Email - Use Caution Thanks. In SynthSeg, if I set a threshold at 0.5 on the segmentation output, should I get exactly the TIV? Label 0 is the background, therefore all the labels above 0 should constitute the TIV. Is this the case?
Best, Marco
From: Iglesias Gonzalez, Juan E. JIGLESIASGONZALEZ@mgh.harvard.edu Date: Tuesday, 1 July 2025 at 05:51 To: Freesurfer support list freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] Re: eTIV in SynthSeg EXTERNAL SENDER The former!
-- Juan Eugenio Iglesias http://www.jeiglesias.com
From: Marco Ganzetti marco.ganzetti@biogen.com Date: Monday, June 30, 2025 at 05:57 To: freesurfer@nmr.mgh.harvard.edu freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] eTIV in SynthSeg
External Email - Use Caution Dear,
I would like to know how the eTIV is estimated in SynthSeg and SynthSeg+ . Is it a combination of CSF+ventricles+WM+GM masks? Or do you estimate is using the registration to MNI space approach?
Best, Marco
freesurfer@nmr.mgh.harvard.edu