Hi,
I am sorry for slight off-topic, but I was hoping that someone on the list may
have a suggestion for me.
I am trying to set up an fMRI of auditory system at 3T. Gradient echo gives me
huge responce (p=0.05, cluster 12), but nothing at all with spin echo (p =
0.05, cluster 3). In theory SE responce should be about 3x smaller than the
GE one, which should be enough, judging by the amplitude of GE responce.
With SE I tried TE=40, 50, 55ms and reducing partial volume effect by going
down with voxel size from 2.5x2.5x3 to 2x2x2.5, but still nothing. I found
studies on PubMed doing SE fMRI at 3T with TE=100ms, but I have slight doubts
about that.
The temporal stability of the series seems to be OK. If I display it as %
signal change in FSLviewer and demean it, there are some spikes exceeding 5%,
but majority of the signal varies in range of -+4%.
What TE and voxel size do you people use with SE at 3T?
Thanks a lot for hints.
Martin
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