PT - JOURNAL ARTICLE AU - J A Hirsch AU - R E Lenkinski AU - R I Grossman TI - MR spectroscopy in the evaluation of enhancing lesions in the brain in multiple sclerosis. DP - 1996 Nov 01 TA - American Journal of Neuroradiology PG - 1829--1836 VI - 17 IP - 10 4099 - http://www.ajnr.org/content/17/10/1829.short 4100 - http://www.ajnr.org/content/17/10/1829.full SO - Am. J. Neuroradiol.1996 Nov 01; 17 AB - PURPOSE To compare proton MR spectroscopic alterations with the degree of contrast enhancement in multiple sclerosis (MS) lesions.METHODS Thirty-five patients with clinically diagnosed MS were studied with MR spectroscopy. A total of 47 lesions were examined. Solvent-suppressed proton spectra were acquired with an echo time of 16 milliseconds using the point-resolved spectroscopic localization method from 1.5 cm3 voxels. Marker peaks/creatine (Cr) ratios obtained from these spectra were plotted against the relative enhancement of the lesion seen after administration of contrast material. The relative enhancement was defined as S(contrast) -S0/S0, where S0 is the signal intensity of a T1-weighted image and S(contrast) is the signal intensity after administration of gadopentetate dimeglumine.RESULTS We found a positive linear relationship between the marker peaks/Cr ratio and the degree of enhancement of the lesion. That is, the marker peaks/Cr ratio was higher in the lesions that showed the greatest enhancement.CONCLUSION The MR/Cr ratio obtained with the use of short-echo-time proton MR spectroscopy correlates with the degree of contrast enhancement. This ratio may therefore serve as a means for evaluating and quantifying the level of inflammatory activity within the plaques of patients with MS.