On May 27, 2015, at 3:16 AM, Stuart Oldham <[email protected]> wrote:

> Hi Donna,
> 
> That is correct that we want the source parcellation mapped on the subjects 
> surfaces. I believe we are wanting it in MNINonlinear stereotaxic space.
> 
> Should I be using the fs_LR standard mesh then? 

I'm not sure what resolution your volumes will be, but try it both ways 
(project from native, project from fs_LR surfaces), and subtract one result 
from the other to see how big the diffs are.  I would expect small.

The fs_LR way is easier, because it is a standard mesh, which means you 
resample from fsaverage (hem-specific) mesh to fs_LR (hems in register) mesh 
once.  Then you can use the same fs_LR parcellation to project from each 
subject's anatomical surface (i.e., parcellation remains constant, while 
surface projection substrate varies across subjects).  With native, you must 
resample the parcellation onto each subject/hem's mesh.

It isn't clear to me, based on your goals, whether you should use the white, 
midthickness, or pial as your substrate.

The FS -> fs_LR resampling is tricky to understand.  See this script:

https://github.com/Washington-University/Pipelines/blob/master/PostFreeSurfer/scripts/FreeSurfer2CaretConvertAndRegisterNonlinear.sh
scroll down to this line and below:

${CARET7DIR}/wb_command -surface-sphere-project-unproject 
"$AtlasSpaceFolder"/"$NativeFolder"/"$Subject"."$Hemisphere".sphere.reg.native.surf.gii
 
"$AtlasSpaceFolder"/fsaverage/"$Subject"."$Hemisphere".sphere."$HighResMesh"k_fs_"$Hemisphere".surf.gii
 
"$AtlasSpaceFolder"/fsaverage/"$Subject"."$Hemisphere".def_sphere."$HighResMesh"k_fs_"$Hemisphere".surf.gii
 
"$AtlasSpaceFolder"/"$NativeFolder"/"$Subject"."$Hemisphere".sphere.reg.reg_LR.native.surf.gii

What you are doing is different, though, because your parcellation is already 
on the fsaverage hem-specific/intermediate mesh.

> With the mri_label2vol command I should be only producing a single output 
> volume. I now input the annotation file into this command, bypassing the need 
> for labels (the computer I am using also has trouble loading in all of the 
> labels).

You might need to mris_convert GIFTI to freesurfer and name per expected 
conventions to get this to work.

> I have a pre-existing script that was written in my lab to create random 
> parcellations and I am attempting to adapt that. So I do the above and I will 
> get a label volume for each hemisphere. Then these two label volumes are 
> combined into a single image. Subcortical parcellations are then added to 
> make a whole brain parcellation image which we then use to make connectomes.
> 
> Sorry if anything is unclear or not elaborated on enough, I am very new to 
> all of this.
> 
> Regards,
> 
> Stuart
> 
> On 27 May 2015 at 07:01, Donna Dierker <[email protected]> wrote:
> Hi Stuart,
> 
> I have fewer answers than questions, but it seems like at the end of this, 
> you want your source (fsaverage) parcellation mapped onto the HCP subjects' 
> surfaces, and then projected from surface to volume (subject's orig/magnet 
> space or MNINonlinear stereotaxic space?).
> 
> The HCP pipeline uses the Freesurfer ?h.sphere.reg to get surface data onto 
> fs_LR mesh:
> 
> lh: freesurfer_native_mesh -> fsaverage.left -> fs_LR (32k or 164k) mesh
> rh: freesurfer_native_mesh -> fsaverage.right -> fs_LR (32k or 164k) mesh
> 
> Note that fsaverage left and right hem meshes are not in register with one 
> another (across hemispheres -- vertex i on the left is probably nowhere near 
> vertex i on the right hem).  In the fs_LR standard mesh, left and right hems 
> are in register with one another.
> 
> It sounds like you have an annotation on the fsaverage mesh.  It seems in 
> principle possible to get your annotation, which is a single, atlas-like 
> parcellation that will be used across HCP subjects, onto the fs_LR mesh, and 
> then you could use the subjects' fs_LR white, midthickness, or pial surface 
> to project the annotation/label to volume somehow, but I don't know how those 
> freesurfer commands work or what they need.  You can mris_convert from GIFTI 
> to Freesurfer format, if needed.
> 
> It might help to zoom out a bit more, though:  What do you plan to do with 
> the resulting individual label volumes?
> 
> Donna
> 
> 
> On May 24, 2015, at 8:45 PM, Stuart Oldham <[email protected]> wrote:
> 
> > Hi all,
> >
> > I am trying to create a random parcellation for the HCP data. I have 
> > created the parcellations first using the fsaverage subject and am trying 
> > to map these onto the HCP subjects.
> >
> > First I have map the annotation from the source (fsaverage) to the subject 
> > using mri_surf2surf (for each hemisphere individually). Usually this just 
> > uses a sphere.reg file but the HCP data doesn't have the file in this 
> > format. Is the {subject}.{hemisphere}.sphere.reg.native.surf.gii (located 
> > under MNINonLinear/Native) the file I should be using here?
> >
> > Next I turn the annotations into labels using mri_annotation2label. Which 
> > surface file do I need to specify it to run (is it the same as above)?
> >
> > Then I run mri_label2vols. Again which surface file should I be inputting? 
> > Should it now be the  {subject}.{hemisphere}.white.native.surf.gii? Also is 
> > there a way with this command I can specify it to find a thickness file 
> > (i.e. {subject}.{hemisphere}.thickness.native.surf.gii) as by default it is 
> > looking for an lh or rh .thickness file.
> >
> > Thanks in advance!
> >
> > _______________________________________________
> > HCP-Users mailing list
> > [email protected]
> > http://lists.humanconnectome.org/mailman/listinfo/hcp-users
> >
> 
> 


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