Pablo,

Registration to F99 should not be impacted by issues of scaling.  (For example, 
it doesn't affect our monkey-to-human registration despite large scale 
differences.)  But if you want to rescale just for the sake of veridical 
representation, you can use 
caret_command -surface-apply-transformation-matrix or Surface: Tranform: Scale 
within Caret.

David

On Jul 20, 2012, at 6:27 PM, Pablo Polosecki wrote:

> Hi Donna,
> 
> Your excerpts were really inspiring. Many many thanks. I got them
> finally well-alligned.
> One more question: My volumes and surfaces have a nominal resolution
> of 1mm but they are actually .5mm (This means we scan at .5 mm
> resolution but we have to trick FreeSurfer into thinking we scan at
> 1mm because it doesn't display things correctly with other resolution
> values). Does this matter for working in Caret and registering to F99?
> Or do I have to rescale all my files back to .5mm?
> 
> Thanks!
> Pablo
> 
> On Fri, Jul 20, 2012 at 5:12 PM, Donna Dierker <[email protected]> 
> wrote:
>> Sorry I'm not as familiar with that script, but I am familiar with scripts 
>> we use for importing human freesurfer files into Caret.  Hopefully these 
>> excerpts might help:
>> 
>> #Find c_ras offset between FreeSurfer surface and volume and generate matrix 
>> to transform surfaces
>> MatrixX=`$FreeSurferInstallationDirectory/bin/mri_info --cras 
>> $InputFreesurferSubjectDirectory/mri/orig.mgz | cut -f1 -d' '`
>> MatrixY=`$FreeSurferInstallationDirectory/bin/mri_info --cras 
>> $InputFreesurferSubjectDirectory/mri/orig.mgz | cut -f2 -d' '`
>> MatrixZ=`$FreeSurferInstallationDirectory/bin/mri_info --cras 
>> $InputFreesurferSubjectDirectory/mri/orig.mgz | cut -f3 -d' '`
>> Matrix1=`echo "1 0 0 ""$MatrixX"`
>> Matrix2=`echo "0 1 0 ""$MatrixY"`
>> Matrix3=`echo "0 0 1 ""$MatrixZ"`
>> Matrix4=`echo "0 0 0 1"`
>> MatrixCRAS=`echo "$Matrix1"" ""$Matrix2"" ""$Matrix3"" ""$Matrix4"`
>> 
>>  for Surface in white pial ; do
>>    caret_command -surface-apply-transformation-matrix 
>> $OutputRootDir/$Subject/$InitialMeshDirectory/$Subject.$Hemisphere."$Surface"_orig.initial_mesh.coord.gii
>> $OutputRootDir/$Subject/$InitialMeshDirectory/$Subject.$Hemisphere.initial_mesh.topo.gii
>>  
>> $OutputRootDir/$Subject/$InitialMeshDirectory/$Subject.$Hemisphere."$Surface"_orig.initial_mesh.coord.gii
>>  -matrix $MatrixCRAS
>>  done
>> 
>> Also, it might matter which volume you use (e.g., orig.mgz vs others).
>> 
>> 
>> On Jul 20, 2012, at 3:55 PM, Pablo Polosecki wrote:
>> 
>>> Hi Donna,
>>> 
>>> I tried converting to RAS (this converst the heder information, which
>>> apparently Caret does use) and the data matrix. The problem is the
>>> same: the axes are correct (i.e., R points to the right side, D is
>>> dorsal, etc). However, the surface and the volume still don't match in
>>> Caret just like before. The issue seems to be some sort of offset in
>>> the center of coordinates (when I click on the surface, the
>>> highlighted points seem to be on a sensible medio-lateral and
>>> dorso-ventral position. The problem is that the highlighted voxel is
>>> too posterior in the volume view). Does this make sense or hint to a
>>> possible solution to you perhaps? Worst case scenario, I could eyeball
>>> how big this translation offset is, open the volume in matlab and have
>>> it translate the data matrix. That way, it would roughly look okay,
>>> but perhaps there is a more graceful way of handling this.
>>> Thank you again,
>>> Pablo
>>> 
>>> On Fri, Jul 20, 2012 at 3:14 PM, Donna Dierker <[email protected]> 
>>> wrote:
>>>> Be aware that what AFNI/Caret calls LPI, Freesurfer calls RAS. ;-)
>>>> 
>>>> Can you try having mri_convert write the volume out as RAS, instead of
>>>> LPI?  Freesurfer will read the header and do the right flipping/rotating
>>>> so that the surface aligns with it.  Freesurfer did the right thing, as it
>>>> understands that label.  But that understanding is not what other software
>>>> desires, in this case.  (At least that's my read of your problem.)
>>>> 
>>>> I think the axes don't need rotating anymore, but all three need flipping.
>>>> 
>>>>> Dear List,
>>>>> 
>>>>> I successfully completed the FS-to-F99 tutorial and now I am trying to
>>>>> reproduce the steps with my own FreeSurfer dataset. According to the
>>>>> FS-to-F99 tutorial, I need to have my mri volume "into LPI
>>>>> orientation" and "the surfaces and volume need to be in register". My
>>>>> original volume is in LIA orientation and is in register with my
>>>>> surface, in the sense that when I open both on FreeSurfer's tkmedit
>>>>> they are well-aligned to each other (I don't know how to check that
>>>>> they are in register otherwise). If I use this surface and volume on
>>>>> FS-to-F99's Stage-1 script and open the resulting spec file with
>>>>> Caret, the volume's axes are wrong and the points on the surface and
>>>>> in the volume don't match (I see this by clicking on the surface and
>>>>> looking what is then highlighted on the volume window). If I transform
>>>>> the volume into LPI orientation (using FreeSurfer's mri_convert
>>>>> command), the new volume has the desired orientation and,
>>>>> interestingly, it is still well-aligned to the surface in FreeSurfer's
>>>>> tkmedit. However, when I use this surface and volume on the FS-toF99's
>>>>> Stage-1 script, the volume and the surface are still not well-aligned,
>>>>> even though the axes labels are now correct. How could I fix things so
>>>>> that my volume and surface are in register when shown in Caret?
>>>>> 
>>>>> Thank you very much,
>>>>> Pablo
>>>>> _______________________________________________
>>>>> caret-users mailing list
>>>>> [email protected]
>>>>> http://brainvis.wustl.edu/mailman/listinfo/caret-users
>>>>> 
>>>> 
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