Thanks a lot Doug for your super rapid response!
I was asking because I previously had the impression that using one run was giving better results, but lately with version 5.3 I've found that averaging 2 runs tends to reduce the amount of topological errors that have to be corrected. But as you said, it may largely be related to the acquisition's quality. Would you generally agree that if the contrast and resolution is good, then averaging two runs may add some "fuzziness" to the averaged scan, whereas it would increase the signal to noise in acquisitions that are not perfect in terms of contrast / resolution?
Marie
On Jul 15, 2013, at 12:04 PM, Douglas N Greve greve@nmr.mgh.harvard.edu wrote:
Hi Marie, I have not seen a publication on it. I've played around with it a bit and could not convince myself that there was a huge win in using 2, but it also depends a bit on your acquisition. If you have a lot of acceleration or really small voxels, then maybe it makes a bigger difference. Also, if you have a population that moves a lot, it might be a good idea to get to scans even if you only use one doug
On 07/15/2013 02:55 PM, Marie Schaer wrote:
Hi all,
Small question related to the number of structural runs required for optimal results: I was wondering whether someone tested the assumption that using two scans rather than one improves the segmentation process and the cortical surface reconstruction / thickness estimation? I've not been able to find any publication on it, but maybe my search was not extensive enough.
Thanks a lot for your answer,
Marie
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