On 2/27/15 3:41 PM, aqure...@nmr.mgh.harvard.edu wrote: > Hi Freesurfer group, > > I wanted to use mris_preproc to calculate regional differences in surface > area between two groups. > > Ideally I would like to use something that is vertex-wise and preserves > regional area, but I've had trouble with spherical demons (using the > Winkler methodology). So I am going to first try using mris_preproc (and > compare the two methods). I found this old thread suggesting that I should > use the --area flag. > But I had some questions: > > 1) Which surfname should I use with the --area flag? area.mid vs area.pial > vs any other file We usually use area (area of the white surface) since mid and pial will have confounding thickness effects.
> 2) Should I use --meas flag in addition and if so which one? (similar to > how --meas thickness is used for calculating cortical thickness) I would use --meas area without using --area. > 3) Which --surfreg file should I use? sphere.reg vs sphere. Or do I not > need the --surfreg? sphere.reg (which is the default) doug > > > Thanks, > Abid > > > ---------- Forwarded message ---------- > From: Anderson M. Winkler <wink...@fmrib.ox.ac.uk> > Date: Tue, May 14, 2013 at 1:19 AM > Subject: Re: [Freesurfer] Usage of --area option in estimating the > vertex-wise maps of surface area > To: free <freesurfer@nmr.mgh.harvard.edu> > > > Hi Xi-Nian, > > As Doug said, they don't do the same thing. The method in the paper > uses a different kind of interpolation to allows the preservation of > the amount of area, whereas mris_preproc achieves the same globally > using a Jacobian correction. The results aren't expected to be > identical at the vertex level or for small regions. > > An implementation of the method we proposed in the paper is available > for Octave and/or Matlab at http://brainder.org/download/areal > It works fine, but beware that it's quite slow. > > All the best, > > Anderson > > > > 2013/5/13 Douglas Greve <gr...@nmr.mgh.harvard.edu> >> >> Hi Xi-Nian, it does not do the same thing, but it does something > similar. Anderson found that it gave similar results in a lot of cases, > but he has found some differences. If he's still following the FS list, > maybe he can comment. >> doug >> >> >> >> >> >> On 5/11/13 9:53 PM, Xinian Zuo wrote: >> >> Hello Doug, >> >> I am doing some association studies between functional measures and > surface area. In using mris_preproc, there is an option --area. Does > this do sth similar to that as Winkler et al. (2012)? >> Winkler et al., 2012. Measureing and comparing brain cortical > surfacearea and other areal quantities. >> Thank you very much. > _______________________________________________ > 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.
