Dear Freesurfers,
I have a dataset processed with a classical recon-all of Freesurfer v.4.3.1 and there are two MRIs that were not segmented correctly due to the register. After several unsuccessful attempts to improve this step using tkregister2, finally I have successfully processed them with FS v5.0. Would it be correct to perform a QDEC analysis to analyse cortical thickness using all my dataset (mixing MRIs processed with FS 4.3.1 and two of them processed with FS 5.0) ?
Thank you for your help, Yolanda
Hi Yolanda,
No. It is better to remove the two subjects. Mixing versions is never a good idea as results are expected to differ. Same is true for different acquisitions (parameters, scanners etc). If anything has to be different it needs to be asserted that it is spread equally among your groups.
Best Martin
On Jun 10, 2011, at 7:16 AM, Yolanda Vives yvives@pic.es wrote:
Dear Freesurfers,
I have a dataset processed with a classical recon-all of Freesurfer v.4.3.1 and there are two MRIs that were not segmented correctly due to the register. After several unsuccessful attempts to improve this step using tkregister2, finally I have successfully processed them with FS v5.0. Would it be correct to perform a QDEC analysis to analyse cortical thickness using all my dataset (mixing MRIs processed with FS 4.3.1 and two of them processed with FS 5.0) ?
Thank you for your help, Yolanda
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
Hi Yoldanda,
which register do you mean? Talairach? You shouldn't mix versions, but you could use the correct Talairach from 5.0 and use it to fix the 4.3.1 run.
cheers Bruce
On Fri, 10 Jun 2011, Yolanda Vives wrote:
Dear Freesurfers,
I have a dataset processed with a classical recon-all of Freesurfer v.4.3.1 and there are two MRIs that were not segmented correctly due to the register. After several unsuccessful attempts to improve this step using tkregister2, finally I have successfully processed them with FS v5.0. Would it be correct to perform a QDEC analysis to analyse cortical thickness using all my dataset (mixing MRIs processed with FS 4.3.1 and two of them processed with FS 5.0) ?
Thank you for your help, Yolanda
freesurfer@nmr.mgh.harvard.edu
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Bruce Fischl -
Martin Reuter -
Yolanda Vives