Hoby Patrick Hetherington1, Kai-Ming Lo2,
William Punchard2, Piotr Starewicz2, Jullie W. Pan1
1Neurosurgery, Yale University, New
Haven, CT, United States; 2Resonance Research Inc., Billerica, MA,
United States
With
the advent of ultrahigh field systems, 7T, significant improvements in
spectroscopic imaging studies of the human brain have been anticipated.
However, these gains are dependent upon the achievable B0 homogeneity, both globally
(over the entire ROI or slice) and locally (the linewidths of individual SI
voxels within the ROI). Our 7T human brain data demonstrates that substantial
improvements in both global and local homogeneity can be achieved using
1st-3rd and higher order shims. The required strengths to achieve higher
order terms (4th and 5th orders) can be obtained using a shim insert and
modest strength power supplies.