Saad said "when you have at least two NON-EQUAL b-values, S0 will be the
zero- crossing," so a single b0 and some number of b!=0 DWIs will count.
Peace,
Matt.
-----Original Message-----
From: FSL - FMRIB's Software Library [mailto:[log in to unmask]] On Behalf
Of Torsten Ruest
Sent: Thursday, March 26, 2009 7:58 AM
To: [log in to unmask]
Subject: Re: [FSL] S0 Image from dtifit
Dear Saad,
thanks very much for your answer. We acquired only 1 b0 image, you said that
at least 2 are needed to fit the data to get 0 diffusion weighting. What
does then happen in case where only 1 b0 image is available?
The next question is then about the MRI acquisition. I was advised from one
side that aqcuisiton parameters between disease and normal should be
identical, including receiver gain. From another source I've been advised to
let the machine sort out the right settings so that, ie a 180 degree pulse
is achieved, which may not be the case with identical gain settings. However
one may argue that the difference in gain settings is due to the disease
when all other parameters are constant and therefore should not be changed
either (ie. should be identical throughout the study). On the other hand
letting the machine adapt the pulse may actually mask a real difference.
This is probably not the right forum to post this question to, but maybe
someone can give advise anyway.
Thanks in advance,
Torsten
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