Re: [Freesurfer] Voxel resolution impact / skull stripping and biascorrection replacement

2008-10-05 Thread Pedro Paulo de Magalhães Oliveira Junior
João, As Bruce said different cohort produce different results. You should expect a thinning in superior temporal, in enthorrinal cortex. Sometimes in AD I haven't found thinning in parietal cortex. But I think you should compare your cohort with the published data with AD and cortical surface ana

RE: [Freesurfer] Voxel resolution impact / skull stripping and biascorrection replacement

2008-10-05 Thread Bruce Fischl
Hi Joao, previous bias correction should be fine, and previous skull stripping (if it's accurate) should as well, assuming you understand the recon-all stream well enough to get into it at the right place. As for the false negatives, can you tell us something about your data? What stage of A

RE: [Freesurfer] Voxel resolution impact / skull stripping and biascorrection replacement

2008-10-05 Thread Joao Pereira
Pedro, Thanks for your reply. By false negatives I mean a lack of detection of atrophic areas which I know are present in this AD cohort, namely the parietal convexities. I'm unable to visualise them with FS. Finally, you've recommended me not to seed anything to recon-all which had been skull s