You can count the number of vertices in an ROI metric file with wb_command
-metric-stats using SUM (the ROI should be the input, you don't need -roi).

Tim


On Tue, Apr 17, 2018 at 7:31 AM, Xinyang Liu <[email protected]> wrote:

> Dear Matt, dear Tim,
>
> Lots of thanks! I have a better understanding now owing to your detailed
> explanation. :)
> By the way, is there any command in the workbench to count the vertex
> number on single surface ROI?
>
> Best regards,
> Xinyang
>
>
> At 2018-04-17 08:11:23, "Glasser, Matthew" <[email protected]> wrote:
>
> It is better to have the termination surface outside the counting surface
> (e.g. count on white, terminate on pial).  I do not remember if they can be
> the same surface or not, so you would need to ask this on the FSL list.
>
> Peace,
>
> Matt.
>
> From: Timothy Coalson <[email protected]>
> Date: Monday, April 16, 2018 at 4:10 PM
> To: Xinyang Liu <[email protected]>
> Cc: HCP 讨论组 <[email protected]>, Matt Glasser <
> [email protected]>
> Subject: Re: [HCP-Users] using surfaces as termination masks
>
> Inline replies.
>
> Tim
>
> On Sun, Apr 15, 2018 at 9:42 AM, Xinyang Liu <[email protected]>
> wrote:
>
>> Dear Matt, dear Tim,
>>
>> Very grateful for both of your kind replies. :)
>>
>> Here are some further questions based on your feedbacks.
>>
>> 1. For the ROI of neocortex (atlasroi.shape.gii), does it mean this
>> shape file includes pial, midthickness and white surfaces? I previously
>> thought the .shape.gii file provides cortical shape information, like
>> curvature.  But then I found the value of each atlasroi vertex is 1. Is
>> it just an atlas map? Why was it chosen to set the value of L/R white.asc
>> in surf2surf for brain surfaces? How do we usually give the --values in
>> surf2surf?
>>
>
> .shape.gii is a file extension, it does not tell you what is in the file.
> It is actually the same file format as .func.gii, and we are not entirely
> consistent about when we choose to use each one.  "atlasroi.shape.gii" is
> just a binary roi, as "atlasroi" is intended to imply - it has values of 1
> on vertices that get used in our standard cifti space, and 0 on vertices
> that don't get used.  There are no coordinates or topology in it, no white,
> no pial, no midthickness - it is not a .surf.gii file, and we don't use the
> "combined data and coordinates" type files that other software does
> (unfortunately, probtrackx requires such "combined" files, adding to your
> confusion).  In workbench, surfaces are always loaded from a different file
> than the data to display on them.
>
>
>> 2. For the CIFTI and GIFTI matrices, I didn't intend to get the value of
>> each element, but preferred to know what kind of data is stored, which
>> might be shown by the name of each column, or data can be recognized as
>> coordinates. I am wondering how to check this.
>>
>
> They can store any type of measure.  You can get the names of the maps, if
> they have been named at all, by using "wb_command -file-information
> -only-map-names <file>".  Cifti files only store data values, and do not
> additionally contain surface coordinates or topology.  You have to load
> surfaces separately from the cifti file.
>
>
>> 3. I could not understand well that the cortex ROI would allow
>> connections to pass through the medial wall. Because when looking at the
>> surface outlines of "L/R.white.32k_fs_LR.surf.gii", it seems that the
>> left and white surfaces are closed regions (please see the figure
>> attached). Then how do connections pass through the middle surfaces?
>>
>
> The atlasroi.shape.gii has values of 0 on the vertices that cut through
> the corpus callosum - if you generate the files correctly, the tractography
> software will see these values of 0 and know not to terminate a streamline
> that hits the surface where the value is 0, and continue until it hits a
> vertex with a value of 1.  You will need to specify the files for both
> hemispheres to the tractography command, I assume.
>
>
>> 4. If we acquire seed ROIs from the midthickness surface, does it mean
>> that the termination surface masks can only come from the pial surface
>> then? Because the white surface is in the inner layer and therefore would
>> stop the streamlines coming from the mid-surface to go inside the brain. Is
>> my understanding correct?
>>
>
> I don't understand this question.  I don't know if it is even possible to
> specify multiple stopping surfaces for one hemisphere in probtrackx.  If it
> were, and you used the white surface as one of them, then it should stop
> all streamlines before they reach midthickness or pial (unless you did
> something wrong).  I think the general guidance is to use the white matter
> surface, as fiber directions become less reliable in gray matter.
>
>
>> Look forward to your further guidance. Many thanks!
>>
>> Best regards,
>> Xinyang
>>
>>
>>
>> At 2018-04-14 05:42:36, "Timothy Coalson" <[email protected]> wrote:
>>
>> Inline comment.
>>
>> Tim
>>
>> On Thu, Apr 12, 2018 at 11:01 PM, Xinyang Liu <[email protected]>
>> wrote:
>>
>>>
>>> 2. How to look at the CIFTI and GIFTI files as matrices? I haven't found
>>> a proper way to look at the information inside as rows and columns.
>>>
>>
>> Gifti files, and dense cifti files, have too many elements to be properly
>> viewed as a matrix, and the vertices that are adjacent in the file data
>> don't make much sense spatially.  If you want a matrix display, you should
>> use a parcellated cifti file (which can be made from a dense cifti file
>> with wb_command -cifti-parcellate).
>>
>> Tim
>>
>>
>> 1.  That is the ROI of neocortex (excluding the medial wall).  The medial
>> wall is the non-cortical tissue that connects the two hemispheres (e.g.
>> corpus callosum, diencephalon).  All of the surface meshes are usable if
>> they are the same kind of mesh (i.e. native, 32k, 164k).
>>
>> 2.  You can convert them to dconn files with wb_command
>> -probtrackx-dot-convert.
>>
>> 3.  The cortex ROI will allow connections to pass through the medial
>> wall.  You can include multiple surface and volume ROIs in probtrackx.
>>
>> Peace,
>>
>> Matt.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
>

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