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Dear Mark Thank you very much for your e-mail In fact the DaTScans are very different to "normal" SPECT or PET, e.g. FDG PET. In the latter you have activity in the entire brain, so I think that normalization to a T1 (maybe after BET) should be possible (although I have no personal experience here). The image of a DaTScan is fundamentally different (see attachment). In fact activity is present only in the basal ganglia. I think that therefore the procedure to normalize the scans should be very different. I like FSL, and I would like to analyze VBM and TBSS. Therefore it would be best to analyze the DaTScan also in FSL, followed by a RANDOMISE analysis Any help is highly appreciated Sven PS: The image was refused (too large). Maybe I can send it to you in another way?? On 16 mars 2011, at 09:29, Mark Jenkinson wrote: > Dear Sven, > > I have no direct experience of DATSCANs but I assume they are similar > to general SPECT or PET scans. We have had success registering > SPECT/PET to MRI before. It is always better to register the SPECT/PET > to that subject's MRI using 6 DOF with FLIRT and a cost function like > mutualinfo or normmi. I would normally choose the best T1-weighted > scan as the reference, but it may depend on what features are most > clearly seen in your DATSCAN. > > Once you've got a good registration of your DATSCAN to your MRI, > then you can register the MRI to the MNI standard space image. > This registration can be done with non-linear (FLIRT then FNIRT) > whereas it is usually very, very bad to try and register the SPECT/PET > with non-linear directly as there are very few features there to drive > that registration. > > When you have the two registrations then you can combine them with > convertwarp to get a non-linear registration from the DATSCAN to > the MNI standard space. > > I do not know what you want in terms of a "specific template of the > basal ganglia" but we have several atlases in FSL, and they include > basal ganglia parcellations. > > All the best, > Mark > > > > On 16 Mar 2011, at 07:37, Sven Haller wrote: > >> Dear all >> >> I would like to normalize DATSCANs to MNI standard space >> I also have 3DT1 (easy using FSLVBM) and DTI (easy using TBSS). >> >> Are there any existing tools for FSL for DATSCANs? >> Is there a specific template of the basal ganglia? >> Any experience whether it is better to perform a linear registration DATSCAN to DTI, and then use the non-linear registration of TBSS, or better directly register DATSCAN to NMI? In that case, how? Linear or non-linear? >> >> Any help is highly appreciated >> >> Sven >>