Hi Bruce,

Actually I also acquired a 1mm dataset at 3T and 7T, which works fine using
FreeSurfer. But I'm trying to compare the results with a 0.6mm (0.5mm later)
dataset of the same subjects scanned at 7T.

I tried selecting a seed point for the cutting planes following your advice
and using the tutorial in the wiki. Instead of using the seed point I
specify mri_fill is looking for another one "in the neighborhood". For
example if I choose the coordinates 193 197 174 mri_fill uses 186 220 216,
resulting in also removing most of the occipital lobe.

Is it possible to force FreeSurfer using the seed point I choose? Or do I
have to do something else so mri_fill recognizes the seed point I choose to
be valid?

Thanks in advance,
Regards,
Falk



-----Original Message-----
From: freesurfer-boun...@nmr.mgh.harvard.edu
[mailto:freesurfer-boun...@nmr.mgh.harvard.edu] On Behalf Of Bruce Fischl
Sent: Thursday, July 30, 2009 2:39 PM
To: Falk Lüsebrink
Cc: freesurfer@nmr.mgh.harvard.edu
Subject: Re: [Freesurfer] Processing data with -noaseg flag

Hi Falk,

can you really not afford the 6 minutes or so of scan time to get  a good
1mm dataset? We have analyzed a bunch of 7T data successfully, although it
probably isn't as automated as 1.5 and 3T. The error you are getting we only
see when you have run out of disk space. It sounds like the surface file is
corrupted. As for the cutting planes, you should be able to select a point
in the pons above the cerebellar peduncle for the brainstem cutting plane.
This should remove the cerebellum, which is required for analysis.

We certainly did many cortical thickness studies before the aseg stuff was
integrated into the stream, so it should be possible, it just requires more
work.

cheers,
Bruce


On Thu, 30 Jul 2009, Falk Lüsebrink wrote:

> Hi FreeSurfers,
>
>
>
> As the subcortical segmentation fails fairly often on my high 
> resolution data I want to skip it by using the –noaseg flag, but I’m 
> currently encountering another issue.
>
>
>
> 1.)    During the –fix stage of –autorecon2 I receive following error
during
> mris_euler_numbers (also if I want to view the lh.orig or rh.orig in
> tksurfer):
>
>
>
> rh.orig: face[233615].v[2] = 119048, but face 233615 not in vertex 
> 119048 face list
>
>
>
> lh.orig: face[196300].v[1] = 100366, but face 196300 not in vertex 
> 100366 face list
>
>
>
> 2.)    Normally the subcortical segmentation is also used to cut both
> hemisphere and to remove the cerebellum. The cutting plane between the 
> hemispheres is done very well, but I have never been able to remove 
> the cerebellum. Do I need to remove it manually or are there some ways 
> to remove it automatically? Is it required to be removed?
>
>
>
> 3.)    I’m interested in measuring cortical thickness only. But do I need
to
> keep something else in mind while not using the subcortical 
> segmentation to process my data?
>
>
>
>
>
> Thanks in advance,
>
> Regards,
>
> Falk
>
>


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