On 12/04/2018 02:17 PM, T and LS wrote:
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Dear Help Desk - I have a few basic questions about freesurfer. I am retired military bomb technician working on a blast TBI initiative and not a research so please bear with me. We are looking at a long term study of bomb technicians and I am curious about the following before moving forward.
- Total number of images processed by freesurver? Is this in the thousands or millions?
Do you mean since FS was created? Probably around 100,000 by now.
- Cohart group data is this from each organization or is there a central pool. e.g. I had a 3D volumetric MRI done with DTI at Washington University in St Louis and am 49yrs old is this only from their pool or larger data base? Any idea number of images in that data base?
I'm not sure what you mean. Can you elaborate? You cannot use DTI as input to freesurfer. Are you talking about the Human Connectome Project (HCP) data from Wash U?
- Standard Deviations, Patient Annual Volume Change and Group Annual Volume change; are these organizations specific or a larger data base.
I'mnot sure what you mean. Are you asking if we have such a data base?
- How accurate are the volumes from a 3T MRI and is there a huge fluctuation if scans are done on the same exact MRI system? e.g. in my scan some of the thicknesses were down to .0013mm and volumes down to .9mm3 = is there a lot of error in those numbers.
The actual values are not accurate downto that level. It is hard to say what the accuracy really is but probably worse than 3%.
Thanks for any information you can provide! It seems there will be a DVBIC site open soon where our school is and I would like to be able to provide some input on this.
Thanks, Todd Sheckley
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