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Comprehensive Autopsy Program for Individuals with Multiple Sclerosis
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Quantitative Susceptibility Mapping of Time-Dependent Susceptibility Changes in Multiple Sclerosis Lesions
S Zhang1,2, T D Nguyen1, S M Hurtado Rúa3
1From the Departments of Radiology (S.Z., T.D.N., S.P., I.K., P.S., Y.W., S.A.G.).
AJNR. American Journal of Neuroradiology
|May 18, 2019
Summary
Magnetic susceptibility in multiple sclerosis (MS) lesions differs based on age and the presence of a hyperintense rim. Lesions with a rim retain iron longer, showing a distinct susceptibility trajectory over time.
Area of Science:
- Neuroimaging
- Magnetic Resonance Imaging (MRI)
- Quantitative Susceptibility Mapping (QSM)
Background:
- Magnetic susceptibility in multiple sclerosis (MS) lesions varies with lesion age.
- Hyperintense rims in MS lesions suggest iron-laden inflammatory cells.
Purpose of the Study:
- To investigate the time-dependent magnetic susceptibility changes in MS lesions.
- To compare susceptibility trajectories between lesions with (rim+) and without (rim-) hyperintense rims.
Main Methods:
- Longitudinal quantitative susceptibility mapping (QSM) scans were performed on patients with MS.
- Lesions were classified as rim+ or rim- based on QSM findings.
- A multilevel growth curve model analyzed susceptibility changes over 1.1–6.1 years.
Main Results:
- Fifty percent of new gadolinium-enhancing lesions were rim+.
- Rim+ lesions were larger than rim- lesions.
- Susceptibility peaked 1-2 years post-enhancement, then decreased.
- Rim- lesions showed faster decay and earlier decline than rim+ lesions.
Conclusions:
- Distinct susceptibility temporal trajectories exist between rim+ and rim- MS lesions.
- Rim+ lesions retain iron for extended periods, influencing their susceptibility over years.
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