HI, FSL experts
I have a question regarding the DTI data acquisition. My question is:
if I acquire b0 with different (larger) FOV as that diffusion weighted
images, will this influence the accuracy of calculating DTI-derived
measures?
For example, I acquire b0 with FOV of 128*128mm2, matrix size of
128*128 (1mm isotropic), but diffusion weighted images of FOV of
64*64mm2, matrix size of 64*64 (1mm isotropic). I keep all of the other
parameters between the larger FOV b0 and smaller FOV b0 the same, like
echo time, and the total readout time for the same T2 decay and
susceptibility distortion. Will the b0 acquired with larger FOV
(128*128) only be different with the b0 acquired with smaller FOV
(64*64) in SNR? If not, what are the sources of the possible intensity
changes between the two b0s and how this could influence the accuracy
of calculated FA?
Your thoughts and help are greatly appreciated.
Longchuan
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