However, only 1 H-MRS allows non-invasive and non-radioactive measurement of Glu metabolism. 1 H-MRS is a MR technique, that takes advantage of the fact that the resonance frequency of certain molecules reflects their structure and, thereby, their identity. 1 H-MRS allows the absolute quantification of Glx, phosphorylcholine and glycerophosphorylcholine (t-Cho), N-acetylaspartate (NAA), creatine (Cre) and myo-inositol (mI).
Source: wiktionary