MR Spectroscopy

The history of nuclear magnetic resonance (NMR) spectroscopy reaches back until 1946 as Purcell and Bloch simultaneously verified nuclear magnetic resonance experimentally in condensed matter. During the 1950s first applications of in vitro NMR spectroscopy to analytical chemistry followed. Two major steps forward were achieved during the 1970s: first MR images were acquired and 2-dimensional NMR spectroscopy was introduced. While the latter finally enabled structure determination of biological macromolecules, in vivo magnetic resonance imaging (MRI) evolved into the modality of choice for examination of soft tissue for instance the human brain. Shortly after introduction of in vivo MRI also first localized in vivo magnetic resonance spectra (MRS) were acquired in the early 1980s. In vivo MRS has evolved during the last 25 years in terms of localization quality and spatial resolution, acquisition speed, artifact suppression, number of detectable metabolites and quantification precision and has profited especially from the significant increase of magnetic field strength that recently became available for in vivo investigations. Today it allows for non-invasive and non-ionizing determination of tissue concentrations and turn-over rates of various metabolites and compounds in animals or humans, is applied for clinical diagnostics and has established as an important tool for physiological research.