So far, I've not found any problems when I've used New Segment to
model skull-stripped images. So far though, the number of scans I've
tried has been pretty small, but I would not envisage there to be too
many issues to consider.
Best regards,
-John
On 17 November 2010 13:09, Julie E McEntee <[log in to unmask]> wrote:
> Dear Franz, Christian-
>
> Depending on image sequence/quality, if you are having problems removing dura/skull adequaltely using/tweaking SPM/VBM8 toolboxes inhomogeneity correction/regularization parameters, you can try using another program (e.g., FSL- BET, MIPAV- N3 & SPECTRE) that may do a better job.
>
> Christian, if one were to do this, would any changes need to be made to VBM8 toolbox processing if beginning with skull-stripped images?
>
> Any comments from anyone else on what considerations, if any, when using SPM's New Segment for VBM if beginning with skull-stripped images?
>
> HTH-
>
> -Julie
>
> Julie E. McEntee, MA, CCRP
> Image Processing Technologist
> Center for Neuroscience & Regenerative Medicine, NIH/USUHS
> The Henry M. Jackson Foundation for the Advancement of Military Medicine
> NIH Clinical Center
> B1N264B
> 301-451-1869
> [log in to unmask]
>
> Department of Psychiatry & Behavioral Sciences
> Division of Psychiatric Neuroimaging
> The Johns Hopkins School of Medicine
> [log in to unmask]
>
> On Tue, 16 Nov 2010 14:44:25 +0100, Franz Riederer <[log in to unmask]> wrote:
>
>>Dear all,
>>
>>I see there is a lot of effort to support people working with structural MRI
>>analyses, and I am grateful for that. Although I got some inspiration from
>>the archives of the mailing list, I could not find an answer for the
>>following problem:
>>In some rare instances grey matter seems classified as white matter (please
>>see attachment, blue arrow). In these instances, the dura over the cortex
>>appears rather bright (lower image). Changing the bias regularisation to
>>"extremely light" instead of the default "very light" seemed to have a minor
>>positive effect.
>>
>>To my surprise, the Unified Segmentation within SPM8 seemed to be less
>>sensitive to this artifact.
>>
>>I also see that this might be a problem of the sequence we used in this
>>subject.
>>
>>I wonder whether there is a way to optimize post processing.
>>
>>Many thanks in advance,
>>
>>
>>Franz
>>
>
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