Motion correction methods for MRS: experts' consensus recommendations.

Long acquisition times due to intrinsically low signal-to-noise ratio and the need for highly homogeneous B field make MRS particularly susceptible to motion or scanner instability compared with MRI. Motion-induced changes in both localization and shimming (ie B homogeneity) degrade MRS data quality. To mitigate the effects of motion three approaches can be employed: (1) subject immobilization, (2) retrospective correction, and (3) prospective real-time correction using internal and/or external tracking methods.