Hi Vincent - I'll take on the tracula-related parts:

2. For tracula, the part of the recon-all output that matters is the
aparc+aseg. The surfaces will play a role only the DWI-to-T1 registration 
(assuming you opt to use bbregister).

3. It's important to check your DWI data for obvious motion artifacts, 
(slices that are much darker than their neighbors). Right now this has to 
be done visually, but it's on my list to produce some motion metrics as 
part of the preprocessing.

4. The ball-and-stick model (that bedpostx fits to your data) is used by 
the tractography algorithm in tracula, but there are no stats produced on 
the parameters of that model currently. That's something that can be added 
in the future as well. Note though that it wouldn't make sense to just 
average f1 or f2 over the pathway, because compartment 1 in one voxel may 
correspond to compartment 2 in some other voxel.

Hope this helps,
a.y

On Fri, 11 Oct 2013, vbrun...@nmr.mgh.harvard.edu wrote:

> Dear Freesurfer experts,
>
> I want to do a quality check on our imaging data. I used the longitudinal
> stream for SBA and as the first step for the longitudinal white matter
> analysis with TRACULA.
> We had two time points in our study and thus, in the freesurfer output
> directory there are 5 folders per subject (2 cross-sectional runs, 2 long
> runs and the base).
>
> 1. Would you recommend to use (all of) the QA_TOOLS on all of these 5
> folders per subject for the SBA?
> 2. Independent of the previous question, for the longitudinal version of
> TRACULA would you recommend to use (all of) the QA_TOOLS on the freesurfer
> base folder only / additional folders?
> 3. In addition to the late visual check for well reconstructed pathways
> with freeview, is there another automated possibility to check the quality
> of the diffusion weighted images beforehand/do you think this is
> necessary?
>
> 4. On another note: If I understand correctly, in TRACULA bedpostX is used
> to reconstruct the pathways but then the mean over the voxels that were
> hit (by the MCMC sampling of the paths) of measures from the tensor model
> are taken as outputs. I wonder, is there also the possibility of using the
> partial volumes f1, f2,.. as output measures?
>
> Best,
> Vincent
> _______________________________________________
> Freesurfer mailing list
> Freesurfer@nmr.mgh.harvard.edu
> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
>
>
>
_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer


The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.

Reply via email to