Dear Lilla,
Thank you very much for your answer and your help. I followed all the
recommended steps (I introduced a white matter mask that will ensure that I amÂ
only
considering diffusion values in the white matter and then also I did corrected
for multiple comparison running mri_glmfit-sim with the option grf as Doug
recommend me).
My question is how can I conclude if there is an increase and/or decrease in
the FA values in one group (for example Patients) versus another group (example
controls).
In other words can we conclude on the FA values based on the GLM
results/clusters from the
http://surfer.nmr.mgh.harvard.edu/fswiki/FsTutorial/Diffusion (I don't see
anymore the image with red and blue clusters posted on this website. Is
something going on?)
Thank you very much!
Antonella
________________________________
From: Lilla Zollei <lzol...@nmr.mgh.harvard.edu>
To: Antonella Kis <ator...@yahoo.com>
Cc: "freesurfer@nmr.mgh.harvard.edu" <freesurfer@nmr.mgh.harvard.edu>
Sent: Tuesday, December 13, 2011 12:02 PM
Subject: Re: [Freesurfer] FA interpretation from cvs registration for group
analysis
Hi Antonella,
> I will appreciate a lot if you can help me understand what is the meaning of
> the results after running after running mri_cvs_register and the GLM group
> analysis.
>
> More exactly, I followed all the instructions from the webpage:
>
> http://surfer.nmr.mgh.harvard.edu/fswiki/FsTutorial/Diffusion
>
> and I wonder if based on the cluster's colours I can say something about my
> FA values in one group related to the other one.
>
> More exactly I am looking to understand if I have an increase in the FA value
> for the controls versus patients or the FA in patients is larger than in the
> control group.
>
> My contrast matrix is C = [+1.00000 -1.00000 ] and I have 30 controls and 32
> patients.
I am not sure how to comment on your outcomes as I don't know anything
about your data. However, the diffusion tutorial that we put together is
a very top-level roadmap on how one might go about voxel-based analysis
of their diffusion data. It is not complete in a sense that you would
want to make sure that there is some further processing done on your data
sets before you start interpreting the results. One is that you would
want to introduce a white matter mask that will ensure that you are only
considering diffusion values in the white matter and then also you would
want to correct for multiple comparison running mri_glmfit-sim. We are
planning on updating this tutorial further for our next course to reflect
all these additional steps.
> What is the age range for the cvs_avg35 space? I wonder if is the best space
> to register my subjects if they are children with age between 6-14.
The atlas was constructed from 35 adults, consisting of males and females
ages 18 to 93.
We have been successul registering pediatric images also in that space,
but the outcome will also depend on the quality of your images.
--Lilla
_______________________________________________
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.
_______________________________________________
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.
