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Dear Marina, if you have created the customized template using all subjects from your samples then everything is fine and you can proceed with the images from step 3 (smwrp1*). The optional step is only thought for the case that you add some more subjects to the sample because it's an ongoing study. For that case it's not necessary to create the template again and you can simply save time by re-using the created template. Best, Christian On Tue, 26 Jun 2018 15:47:35 +0100, Marina Blūma <[log in to unmask]> wrote: >Dear Dr. Gaser, Dear CAT12 experts, > >For a study of patients with Alzheimer’s dementia we want to use a customized DARTEL Template. >To do so, I was following the CAT12 Manual, but have come to a bit of a conundrum. Could you kindly clarify what is the correct procedure? > >So far I had performed these steps: >1) Segment data >2) Run DARTEL (create Template) >3) Normalize to MNI space (output: smwrp1*_affine.nii) > >The next step, however, is marked with a word “optionally” (re-use of customized DARTEL Template on age-wise close data) and, thus, it is a bit unclear to me whether it has to be performed or not. > >Searching in the SPM archives, I found following opinions: > >>2016-08-11 MRI More <[log in to unmask]>: >> >>> "You really only have to repeat the segmentation module if you think that >>> the first affine registration is going to differ to a relevant part from an >>> affine registration onto the study-specific template." > > >>2016-08-10 Marko Wilke <[log in to unmask]>: >> >>> Hence, my question is whether the images coming out of step 3 >>> (smwrp1*_affine.nii) are the images already registered to the customized >>> template? > >>>No, otherwise the 4th step would not be necessary. You need to do two rounds: >> one, to segment your data based on a standard template, then use the affine->> registered images to create your own DARTEL template, then repeat the >>> segmentation with your own template. > >Thus, could you please clarify whether the “smwrp1*_affine.nii” images of the first segmentation round are affine-registered to DARTEL? If so, is it still advisable to repeat the segmentation? What is the benefit of this procedure and in which case it might be helpful? > >I would be very grateful for any input on my question. > >Best regards, >Marina >--- >M.S. in Interdisciplinary Neuroscience, Dipl. in Clinical Psychology >Marie-Curie Early Stage Researcher under ITN-ETN H2020 BBDiag project >Dept. Physiology and Pharmacology >Sapienza University of Rome