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jesper: Sorry for my stupid question, :-) Just want to make sure with you. For --super, seems no any input parameter needed, is it correct? and should I set --superlevel also? Best, Ping > Date: Sat, 24 Jan 2009 13:40:11 +0000 > From: [log in to unmask] > Subject: Re: [FSL] template for fnirt > To: [log in to unmask] > > Dear Ping, > > > My subjects are old people, when I trying to normalize my subjects to MNI > > template, the ventricle seesms a little more mis-registration. > > So I am wondering if anybody knows some template for aged people? > > For my situation, should I pick one subject from my study as template and > > normalize others to it? > > I would suggest the following strategy for creating a custom template for > your elderly subjects. > > 1. Register all subjects to the MNI152 template using the "usual" > configuration file. > 2. Use applywarp to resample all your subjects to the template space, > setting the --super flag (for super-sample). Using --super means you will > preserve more of the information from your original image. > 3. Create a new template by averaging the registered images, calling it > e.g. MNI152_elderly_T1_2mm. > 4. Register all subjects again, now to the MNI152_elderly_T1_2mm template. > When doing this you can pass each subjects previous warp-file as input to > fnirt using the --inwarp parameter. If you do that you can change the > schedule in the configuration file to include only the final two steps, > but that is not neccessary and would only save you execution time, not > alter your results. > 5. Goto step 2. Repeat this until the new template is "identical" to that > in the previous iteration. > > Folowing these steps you will have a template that is approximately in > MNI152 space, but wich accomodates some of the widened ventricles in your > population. You will also have a template where the contrast is closely > matched to your particular scanner/sequence, which means that subsequent > registrations to this template will be more robust. > > Good luck Jesper _________________________________________________________________ MSN新版在线社交网络，与您的MSN好友更全面互动！ http://im.live.cn/msn9/