Mario Gilberto Baez Yanez1,2, Phillip Ehses1,3, and Klaus Scheffler1,3
1Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, 2Graduate Training Centre of Neuroscience, Tuebingen, Germany, 3Department of Biomedical Magnetic Resonance, University of Tuebingen, Tuebingen, Germany
The
excellent sensitivity and stability of BOLD-imaging with balanced SSFP (bSSFP)
on humans at 9.4T has been demonstrated in a recent paper. Here, we analyze the
signal change of bSSFP for different vessel (spheres) sizes and susceptibility
differences for different repetition times and flip angles using Monte Carlo
simulations and experiments on micro spheres, and compare it to gradient echo
EPI. Simulated and measured signal changes (using values of susceptibility
changes and vessel sized comparable to a typical BOLD experiment at 9.4T) of
bSSFP are in the range of 10 to 15% with a peak sensitivity to the vessel
(sphere) size at about 3 mm, and a decreased sensitivity for larger
vessels (spheres). For GE-EPI, signal changes are similar to bSSFP, however, no
selectivity to small vessels is visible
