PT  - JOURNAL ARTICLE
AU  - Irina Mader
AU  - Werner Roser
AU  - Ludwig Kappos
AU  - Gisela Hagberg
AU  - Joachim Seelig
AU  - Ernst W. Radue
AU  - Wolfgang Steinbrich
TI  - Serial Proton MR Spectroscopy of Contrast-enhancing Multiple Sclerosis Plaques: Absolute Metabolic Values over 2 Years during a Clinical Pharmacological Study
DP  - 2000 Aug 01
TA  - American Journal of Neuroradiology
PG  - 1220--1227
VI  - 21
IP  - 7
4099  - http://www.ajnr.org/content/21/7/1220.short
4100  - http://www.ajnr.org/content/21/7/1220.full
SO  - Am. J. Neuroradiol.2000 Aug 01; 21
AB  - 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 ± 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.