On Wed, 2 Feb 2005, Brian T. Quinn wrote: > i would not advise averaging data from two separate visits. > use one or the other.
The auto-align feature aims to offer a fair degree of consistency between session scans, but if this was not the case (and it often isn't, because you cannot control for the position of the coil, etc.), then definitely be prepared to ditch the worse scan. Unfortunately! > On Wed, 2 Feb 2005, Evelina Busa wrote: > > > Hi again, > > > > If the shadowing/rimming effect appears to be because of an artifact in > > one of the scans, then you might be better off to exclude that > > acquisition. But if each of the individual scans looks okay, then it does > > sound like improving your lousy average is dependent upon getting a better > > talairach transform. You can do this by trying various talairach scripts > > or even registering it manually. > > > > > > > > On Wed, 2 Feb 2005, Margaret Duff wrote: > > > >> The one using the orig is really horrible looking, very distorted and > >> rotated. I tried using the brain volume, and it looks better, but also > >> has a rimming/shadowing effect. > >> > >> On Wed, 2 Feb 2005, Evelina Busa wrote: > >> > >>> > >>> Hi Margaret, > >>> > >>> How does the talairach transform look? > >>> > >>> On Wed, 2 Feb 2005, Margaret Duff wrote: > >>> > >>>> Hello, I am trying to reconstruct brains of patients who had one > >>>> structural scan during each of 2 visits, a month apart. I averaged the > >>>> two images together, but since they are from different visits, they look > >>>> very badly lined up. It looks like there is one image and another image > >>>> overlaid and shifted by a cm or so. These are clearly wrong and will not > >>>> work but I was wondering if it was OK to run freesurfer with only one of > >>>> the images, or if there was a way to line these two images up better so > >>>> they can be combined? Thanks, Margaret > >>>> > >>>> _______________________________________________ > >>>> 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 > > > > -- _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
