Metabolic differentiation of human brain tumors with in vivo H-1 MR spectroscopy

The authors present H-1 MR spectroscopy results in patients suffering from different intracranial tumors (eg, glioma, lymphoma, craniopharyngioma, metastasis). Measurements were performed at 1.5 T, using the regular head coil for both imaging and spectroscopy. Eighteen patients were examined. All tumor spectra revealed distinct abnormalities as compared with normal brain spectra. Some tumors showed changes in the choline and creatine resonances, whereas in all tumors the N-acetyl aspartate signal decreased significantly. In some cases we observed signal intensity in the spectral range from .9 to 1.7 ppm, presumably corresponding to lipid signals. In two cases (glioma grade III and IV) an abnormally high lactate level could be detected. These observations are the first demonstration that H-1 MR spectroscopy can be used to discriminate and evaluate brain tumors in situ on the basis of spectral differences