Dear FSL list
this is a question not directly related to FSL but I am a bit lost for
an alternative place to ask for advice. I have acquired multiecho T2
images to study relaxation times in a patient group. i found that for
the first echo image (13ms) the CSF signal is actually darker than in
the second echo image (26ms) by about 10%. i have acquired 8 echos and
for the final echo image (132ms), the CSF signal is only 3% darker than
for the second echo.
My question is, does anyone have any idea why the first echo would be
darker than the second. i had presumed that the earlier the echo is
collected, the more signal there is. is that true in practice?
thanks in advance
Scott
========================
Scott Kolbe
Postgraduate Student
Neuroimaging Group
Howard Florey Institute &
Centre for Neuroscience
University of Melbourne
VIC, Australia, 3010.
ph: +61 3 8344 1887
email: [log in to unmask]
website: http://www.neuroimaging.org.au/index.php?id=383
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