***************
TalXFM = [1.040797, 0.011370, -0.069615, -0.863770;0.031794, 0.939578, 0.254677 ,-32.126083; 0.048458, -0.236663 ,1.101207, -20.946930];
Norig = [-1.00000 , -0.00000 , -0.00000 , 130.38606 ;-0.00000 , 0.00000 , 1.00000, -109.95447 ;-0.00000, -1.00000 , 0.00000 , 150.14441 ; 0.00000, 0.00000 , 0.00000 , 1.00000];
Torig = [-1.00000 , 0.00000 , 0.00000 , 128.00000; 0.00000 , 0.00000 , 1.00000, -128.00000; 0.00000 , -1.00000 , 0.00000 , 128.00000; 0.00000 , 0.00000 , 0.00000 , 1.00000];
W = TalXFM * Norig * inv(Torig);
Volume_RAS = [1, -30, 1, 1];
MNI_Talairach = W * Volume_RAS' % Coincides with Tkmedit
% MNI_Talairach = (0.9133; -37.3562; 7.5331)
Volume_RAS = pinv(W)*MNI_Talairach % DOES NOT COINCIDE
% Volume_RAS = (0.4324; -2.9014; 8.7350; 3.8992) >> shouldn't be [1, -30, 1, 1]; ?
********************
Is the transformation two-way? Should it be?
Many thanks again for your help,
Gari
Hi Gary, you would use the MNI305 space as the common space. Eg, Case 2 shows you how to go from RAS of a subject to MNI305 space. You would reverse that to go from MNI305 space to another subject's RAS space thus allowing a RAS-RAS transform. If you have a surface overlay for a subject, you can use mri_surf2surf to transfer it to another subject.
doug
On 3/12/13 11:54 PM, Garikoitz Lerma-Usabiaga wrote:
Thanks Doug,I've seen the page, but I understand that everything is within the same subject. I want to find the equivalencies between subjects. I mean, the plane y = 30 in fsaverage, will correspond to a plane with a bigger Y for a larger head (could be defined anatomically, the most outer point of the hippocampus, for example.
When finding equivalencies for surface ROIs from one subject to another we used label2label for example. If I have an overlay in volume space, how should I "move" it to another subject?
Thanks again,Gari
Hi Gary, check out this wiki page and let me know if you still have questions
http://surfer.nmr.mgh.harvard.edu/fswiki/CoordinateSystems
doug
On 3/12/13 8:04 PM, Garikoitz Lerma-Usabiaga wrote:
Hi!how can I translate a coordinate in talairach space of one subject (Colin27), to every subject in a study? For example, I would like to know where is the coordinate Y = +30 Talairach of Colin27 in Subject_00, Subject_01, etc.
Should I use vol2vol to create a volume for every subject? Is there any direct method with register matrices or something like that?
Thank you very much,Gari
_______________________________________________ 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.