. Author manuscript; available in PMC: 2020 Apr 23.

Published in final edited form as: Magn Reson Med. 2019 Mar 28;82(2):527–550. doi: 10.1002/mrm.27742

Table 1.

SVS acquisition consensus summary.

Aspect	Consensus
Localization method	Chemical shift displacement less than 4% per ppm. 3 T: semi-LASER with OVS (preferred) or OVERPRESS with VSS. 1.5 T: semi-LASER with OVS (preferred) or PRESS.
Echo and repetition time	TE as short as possible (typically 30 ms). Longer TEs may be preferred for lactate (144 or 288 ms), at TEs optimized for specific metabolites such as 2HG detection, as well as for enhanced lipid suppression. TR 1.5 s at 1.5 T, 2.0 s at 3 T.
Number of averages, voxel dimensions and sampling parameters	128 averages collected from a 15 x 15 x 15 mm³ VOI at 3 T. 64 averages from a 20 x 20 x 20 mm³ VOI at 3 T. 256 averages collected from a 15 x 15 x 15 mm³ VOI at 1.5 T. 128 averages from a 20 x 20 x 20 mm³ VOI at 1.5 T. Spectral sampling of 1024 complex data points from 2000 Hz spectral width at 1.5 T or 3 T.
Water reference acquisition	Recommended in all cases. Collect with the same sequence parameters as the water-suppressed scan, but without water suppression and the transmitter frequency set to the water resonance. A single average should be collected with a pre-acquisition delay time of at least 9s to prevent T1-weighting.
B₀ shimming hardware	2^nd order shim coils with adequately powered amplifiers are recommended at 3 T.
B₀ shimming algorithm	Methods incorporating shim strength limits and instability counter-measures are preferred over unconstrained approaches.