Proton MR spectroscopy in neoplastic and non-neoplastic brain disorders.

The basic principles of proton MR spectroscopy as well as newer and more advanced related techniques are reviewed. Spectroscopy is capable of differentiating normal from pathologic brain and provides tissue specificity greater than that of imaging in many instances. Spectroscopic mapping allows for the visualization of the concentration of different metabolites and their distribution within a lesion. This article emphasizes the utility of proton MR spectroscopy in the diagnosis of brain tumors, postradiation therapy changes, infections, degenerative brain disorders, hepatic encephalopathy, ischemia, and demyelination.