The current recommended strategy is to use the Segment option in SPM5. You
should find that it is pretty simple and straightforward to use.
Best regards,
-John
On Monday 13 February 2006 18:30, Jonathan Ipser wrote:
> Hello,
>
> I am part of a team that has been looking at structural changes in the
> brain following a clinical trial of typical antipsychotics for patients
> with schizophrenia. We have at our disposal dual-echo proton density and t2
> MRI images for a total of 45 patients (though for 17 we have only baseline
> images).
>
> We are considering using optimized VBM (ala Good 2001) in analysing the
> volumetric changes between the treatment and control groups. We have
> piloted the analyses using t2 images for a couple of patients, and have
> thus far noticed very little misclassification of dura and scalp as grey
> matter. As this is (as far as I can tell) the main rationale for using
> optimised as opposed to standard VBM, our question is whether optimised VBM
> is necessary when using t2 as opposed to t1 images? Would we be justified
> in skipping the optimisation sequence, or is it likely that the effective
> exclusion of the non-brain matter we have observed so far is likely just a
> consequence of the limited sample we have tested thus far?
>
> On a related note, would we be justified in skipping the optimisation
> sequence if we extract non-brain matter prior to SPM analyses using an
> utility such as BET, for instance?
>
> Thanks,
> Jonathan Ipser
> University of Cape Town
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