Moheet A, Emir UE, Terpstra M, Kumar A,
Eberly LE, Seaquist ER, Oz G.
Initial experience with seven tesla magnetic resonance
spectroscopy of hypothalamic GABA during hyperinsulinemic
euglycemia and hypoglycemia in healthy humans.
Magn Reson Med. 2013 Feb 19
Spectral quality obtained at 7T from the occipital cortex (a) and hypothalamus (b) and B1+ shimming results in the hypothalamus of a healthy volunteer. 1H MR spectra (right in a and b) were obtained with STEAM (TR=5 s, TE=8 ms, TM=32 ms, 128 transients) from the volumes-of-interest shown on T1-weighted mid-sagittal and coronal images (left in a and b). The hypothalamus spectrum was acquired with a 16-channel transceive array coil, while the occipital cortex spectrum was acquired with a quadrature half-volume transceiver. The FIDs were multiplied with a gaussian function (σ=0.08 s) before Fourier transformation. The marked resonances are: NAA, creatine, choline, myo-inositol, and GABA. (c) The region-of-interest (red circle) used for B1+ shimming for the hypothalamus VOI (white square) is shown on a transverse T1-weighted image together with maps of the fraction of available B1+ before and after B1+ shimming.