Quantitative MRS study of Baló's concentric sclerosis lesions.

Baló's concentric sclerosis (BCS) lesions display specific metabolite changes detected by magnetic resonance spectroscopy (MRS). We report on two cases of BCS lesions examined by MRS; the first case was evaluated 36 days after the onset of symptoms, whereas the second case was evaluated 9 days after the onset of symptoms. MRS data were obtained from single voxels located in the lesion and in the contralateral region. Relative to the creatine/phosphocreatine peak, BCS lesions displayed decreases of N-acetyl aspartate and increases of choline, myo-inositol (mI), glutamine/glutamate (Glx), lactate and lipid+macromolecule signals, in agreement with previous reports. In addition, previously unreported decreases of mI (-19% to -29%) and increases of Glx (+55% to +198%) were measured; these could be useful in characterizing BCS lesions.