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Dear Audrey, I guess there will be no advantage in using the VBM tools for estimating normalization parameters for other modalities than T1. You will probably increase normalization quality for T1 images, but the crucial point is the coregistration between the T1 and the perfusion image. I would recommend a simple normalization of the T1 image to the T1 template after coregistration to the perfusion image. I don't have experiences with perfusion images, but considering the limited number of slices your attached normalization result is not bad. If you coregister images with limited FOV, it's often helpful to define anterior commissure in both images and to roughly correct different positions using the display tool. However in your image this seems to be ok. Best regards, Christian -- ____________________________________________________________________________ Christian Gaser, Ph.D. Department of Psychiatry Friedrich-Schiller-University of Jena Philosophenweg 3, D-07743 Jena, Germany Tel: ++49-3641-935805 Fax: ++49-3641-935280 e-mail: [log in to unmask] http://dbm.neuro.uni-jena.de On Wed, 26 Jan 2005 22:22:08 -0800, Audrey Duarte <[log in to unmask]> wrote: >Hello, I am working with data from an AD population and have used Christian >Gaser's create template and optimized VBM procedures in order to generate >the template and priors and also the normalization parameters (from VBM) to >apply to perfusion MRI images. The perfusion images are 7 slice and have >been masked for gray matter and partial volume corrected. I used the >default [2 2 2] dimensions when I applied the normalization parameters to >the perfusion image. I also wrote the normalized image with [1 1 1], since >this is how the parameters were generated in the first place in VBM. The >normalized perfusion image looks strange to me (with both [1 1 1] and [2 2 >2]) and I am unsure what the best procedure for normalization might be in >my case. I have attached the normalized perfusion image [2 2 2]. Thanks! Audrey > >BTW: the dimensions of the perfusion image before normalization were 128 x >128 x 7 with 2.34 x 2.34 x 10 voxels. The warped T1 image from VBM was 157 >x 189 x 156. My T1 template and priors looked very good. > > >Audrey Duarte, Ph.D. >Postdoctoral Researcher >San Francisco VAMC >4150 Clement St, Mail stop:116R >San Francisco, Ca 94121 >415-221-4810 x 3852 >