Hi - these look like pretty poor images - quite bad grey-white
contrast - I'm not sure I'd want to do anything quantitative with
them. Anyway, probably the issue in the CC is a separate thing - it
looks like it has strong localised bias field - so you might play with
reducing or increasing the bias field related options in FAST (i.e.
the smoothing of the field and the number of main loop iterations)
Cheers.
On 8 Jul 2009, at 20:02, Valerie Cubon wrote:
> Hi,
>
> I am experiencing some strange segmentation issues with fast v4. It
> appears
> to do a poorer job than fast v3 with wm/csf/gm segmentation for a
> couple of
> my subjects (especially in the corpus callosum).
>
> Please see the image called 'segment_issues.png' which shows
> results from fast v4, fast v3, and the original image to be
> segmented. It
> was uploaded under the reference number 570235. [Hopefully I did this
> correctly...please let me know if you don't receive it].
>
> Any ideas why fast v4 might be having so much trouble performing the
> segmentation?
>
> Thanks in advance for your help,
> Valerie
>
---------------------------------------------------------------------------
Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
---------------------------------------------------------------------------
|