Magnetic resonance spectroscopy in the recognition of metabolic disease.

Magnetic resonance (MR) is rapidly entering many fields of clinical medicine following a long history as a powerful tool in physics and chemistry. The non-invasive and non-destructive property of this technique has enabled the chemical shift in higher magnetic fields to be exploited to identify and quantitate metabolites in both in vitro and in vivo analysis. High resolution proton spectroscopy of body fluids has been shown to be complementary with established analytical techniques, while the development of whole body large bore magnets is enabling both the study of structure and metabolism in humans in vivo. Phosphorus MR spectroscopy has provided a method of monitoring ATP production and utilisation in situ in both perfused preparation and intact tissue. In human muscle it has been possible to test established theories of tissue energy metabolism. It provides a unique method with which to evaluate the state of tissue oxidative metabolism. The opportunities afforded by other nuclei are being studied, but the low sensitivity of the MR technique forces limitations. Recent technical advances in tissue localization have as yet only been applied in a limited way. The use of MR in metabolic disease will be considered with specific reference to disorders of skeletal muscle metabolism.