Deborah Diane Douglas1, Ivan Dimitrov1,2,
Jimin Ren1, A. Dean Sherry1, Craig R. Malloy1
1Advanced Imaging Research Center,
University of Texas Southwestern Medical Center, Dallas, TX, United States; 2Philips
Medical Systems, Cleveland, OH, United States
Highly
inhomogeneous B1 pose challenges in 7T MRS, even more so when
surface coils are used. Still, the high sensitivity of surface coils makes
them a valuable tool in MRS. While the idea of B1-shimming with
dielectric pads for imaging is well-known, their use in spectroscopy has not
been evaluated. We demonstrate the use of D2O bags in directed
extending the sensitivity volume of surface coils: using a coil under the
calf of volunteers the SNR of tibial bone spectra was increased 4-fold when a
D2O bag was put on top of the leg vs. when no bag was present.