Hi Antonin,

in most cases it should be sufficient to only edit wm.mgz in the base, instead of editing all time points. This is a big time saving especially if you have many time points.

I don’t think merging edits from cross will work well, as there could be atrophy and lots of non-linear deformations in some of the fast progressing brains.

Best, Martin

On 23 Jan 2017, at 23:11, Antonin Skoch ansk@ikem.cz wrote:

Dear experts,

I am currently starting longitudinal analysis of data I previously corrected in cross-sectional stream (FreeSurfer v5.3). The analysis comprises quite large number of subjects - approx 150 subjects, each scanned twice. All subjects are already inspected and errors corrected in cross-sectional analysis. Some of them needed quite large edits, mainly to the wm.mgz and the whole process took large time.

As I read the documentation, the wm.mgz edits in cross are not currently transferred to base. However, wm.mgz has to be correct in base in order to estimate surfaces correctly. From this it implies to me that I would need to edit all wm.mgz errors in base again. Do you think that it could be possible/reasonable to transfer some wm.mgz edits from cross to base, for example to make intersection of edits of all cross timepoints and to transfer it to the base? This could significantly reduce time spent on edits. Does it make sense?

Regards,

Antonin Skoch

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