@article {Mader1220, author = {Irina Mader and Werner Roser and Ludwig Kappos and Gisela Hagberg and Joachim Seelig and Ernst W. Radue and Wolfgang Steinbrich}, title = {Serial Proton MR Spectroscopy of Contrast-enhancing Multiple Sclerosis Plaques: Absolute Metabolic Values over 2 Years during a Clinical Pharmacological Study}, volume = {21}, number = {7}, pages = {1220--1227}, year = {2000}, publisher = {American Journal of Neuroradiology}, abstract = {BACKGROUND AND PURPOSE: The time courses of total creatine (Cr), N-acetylaspartate (NAA), choline (Cho), and myo-inositol have not previously been investigated in the follow-up of contrast-enhancing multiple sclerosis (MS) plaques. Therefore, over a period of 2 years, we compared the absolute concentrations of these metabolites between patients treated with a placebo or 15 {\textpm} deoxyspergualin (DSG) and between clinical groups with relapsing-remitting or secondary-progressive MS.METHODS: Sixteen patients, recruited from a pharmacological study of DSG, and 11 healthy control subjects were investigated by a stimulated-echo acquisition mode sequence (TR/TE = 3000/20). The selected volume initially contained a contrast-enhancing plaque, which was followed up for a period of 2 years.RESULTS: In contrast-enhancing plaques, Cho was significantly elevated and showed a significant reduction after both 3 and 12 months. The initially normal Cr significantly increased between 3 and 12 months, and was negatively correlated with plaque volume on T1-weighted MR images. NAA initially showed normal values, a significant decrease at 1 month, and a slow recovery over 2 years. Myo-inositol did not show a clear tendency. The placebo group did not differ from the treated group, nor did the relapsing-remitting group differ from the secondary-progressive group.CONCLUSION: The contradictory time courses of Cr and NAA show that an absolute quantification in proton MR spectroscopy in MS is necessary to avoid a false interpretation of reduced NAA/Cr ratios. The increase in Cr is probably due to remyelination. The initial dip and later recovery of NAA seem to be related to diminishing edema and remyelination.}, issn = {0195-6108}, URL = {https://www.ajnr.org/content/21/7/1220}, eprint = {https://www.ajnr.org/content/21/7/1220.full.pdf}, journal = {American Journal of Neuroradiology} }