Related Experiment Video
Updated: Jun 7, 2026
Comprehensive Autopsy Program for Individuals with Multiple Sclerosis
Published on: July 19, 2019
Proton MRS of large multiple sclerosis lesions reveals subtle changes in metabolite T(1) and area
E E Brief1, I M Vavasour, C Laule
1Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada.
Abstract:
The T(1) values of metabolites were measured in eight subjects with clinically definite multiple sclerosis (MS) having at least one large brain lesion (2.6 ± 0.7 mL) and in eight age- and sex-matched healthy controls. MRS examinations were conducted at 1.5 T using point-resolved spectroscopy (PRESS) (TE = 30 ms, TR = 530, 750, 1200, 1500, 3500, 5000 ms). Spectra were acquired from a voxel placed in the largest lesion in the subject with MS, and in a corresponding voxel (same size and region) in normal white matter (NWM) in the matched control, and were fitted using LCModel. As there are regional variations in metabolite and water T(1) and metabolite signal areas, careful placement of the control voxel was necessary to measure subtle differences between the lesions and NWM. The T(1) and T(1)-corrected signal areas of creatine were the same in MS lesions as in controls. The T(1) values of choline were significantly shorter in MS lesions located in occipital and parietal, but not in frontal, white matter. N-Acetylaspartate (NAA) and myoinositol T(1) values in MS lesions were similar to those in NWM; however, the area of myoinositol correlated directly with lesion water T(1), and the area of NAA correlated inversely with lesion water T(1). MR spectra acquired at short TR require T(1) correction of choline for accurate quantification. Careful voxel placement in controls to match lesion location in subjects with MS enables a clearer view of the subtle changes in lesions.
Insights
Multiple sclerosis (MS) brain lesions show altered choline T(1) values, particularly in occipital and parietal white matter. Accurate quantification requires T(1) correction for choline, especially at short repetition times (TR).
Area of Science:
- Neuroimaging
- Biophysics
- Medical Physics
Background:
- Multiple Sclerosis (MS) is a demyelinating disease affecting the central nervous system.
- Brain lesions in MS exhibit altered tissue properties detectable by Magnetic Resonance Spectroscopy (MRS).
- Understanding metabolite T(1) relaxation times is crucial for accurate in vivo quantification.
Purpose of the Study:
- To measure T(1) values of metabolites in MS brain lesions and compare them to normal white matter (NWM).
- To investigate the impact of T(1) variations on metabolite quantification in MS.
- To assess regional differences in metabolite T(1) values within MS lesions.
Main Methods:
- MRS examinations were performed at 1.5T using the Point-Resolved Spectroscopy (PRESS) sequence in eight MS patients and eight healthy controls.
- Spectra were acquired from large MS lesions and corresponding NWM voxels across various repetition times (TR).
- Data were processed using LCModel, with careful voxel placement to match lesion and control regions.
Main Results:
- T(1) and T(1)-corrected signal areas of creatine were similar between MS lesions and NWM.
- Choline T(1) values were significantly shorter in MS lesions in occipital and parietal white matter, but not frontal.
- N-Acetylaspartate (NAA) and myoinositol T(1) values were similar, but their signal areas correlated with lesion water T(1).
Conclusions:
- Choline T(1) values are altered in MS lesions, varying by location.
- Accurate quantification of metabolites like choline in MS lesions necessitates T(1) correction, especially at short TR.
- Precise voxel placement is essential for detecting subtle metabolite changes in MS lesions.
