We have three 7T scans of the same person done on separate days. After running all three T1 images using the "recon-all" function, we obtain thalamic volumes. The volumes varied by up to 25% which seems quite drastic for the same person. Is there a way to decrease this variability? Are there some parameters to change for 7T? Would the subcortical segmentation work better with a T2 or DTI image?
Thanks in advance, Ben
Hi Ben
if you upload the datasets we will take a look. I imagine this is due to dielectric resonance effects. What sequence did you use?
Bruce On Tue, 6 Oct 2015, Benjamin Peterson wrote:
We have three 7T scans of the same person done on separate days. After running all three T1 images using the "recon-all" function, we obtain thalamic volumes. The volumes varied by up to 25% which seems quite drastic for the same person. Is there a way to decrease this variability? Are there some parameters to change for 7T? Would the subcortical segmentation work better with a T2 or DTI image? Thanks in advance, Ben
Bruce, Thank you for such a quick response. I have attached a link to the T1 dicom files. The T1 was acquired using an MP rage sequence. Thalamic T1 Files https://docs.google.com/a/umn.edu/folderview?id=0B1unp6YW0CrXc18zckIteUcyYTg&usp=drive_web Thanks, Ben (University of Minnesota, Noam Harel's Lab)
On Tue, Oct 6, 2015 at 11:45 AM, Bruce Fischl fischl@nmr.mgh.harvard.edu wrote:
Hi Ben
if you upload the datasets we will take a look. I imagine this is due to dielectric resonance effects. What sequence did you use?
Bruce On Tue, 6 Oct 2015, Benjamin Peterson wrote:
We have three 7T scans of the same person done on separate days. After running all three T1 images using the "recon-all" function, we obtain thalamic volumes. The volumes varied by up to 25% which seems quite
drastic
for the same person. Is there a way to decrease this variability? Are
there
some parameters to change for 7T? Would the subcortical segmentation work better with a T2 or DTI image? Thanks in advance, Ben
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