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Updated: May 24, 2026
Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
Iron deposition in multiple sclerosis lesions measured by susceptibility-weighted imaging filtered phase: a case
Jesper Hagemeier1, Mari Heininen-Brown, Guy U Poloni
1Buffalo Neuroimaging Analysis Center, University at Buffalo, Buffalo, New York, USA.
Purpose:
To investigate phase lesions identified on susceptibility-weighted imaging (SWI)-filtered phase images in patients with multiple sclerosis (MS), clinically isolated syndrome (CIS) and healthy controls (HC). To relate phase lesion characteristics to other clinical and MRI outcomes.
Materials And Methods:
95 relapsing-remitting (RR), 40 secondary-progressive (SP) MS patients, as well as 19 CIS patients and 49 age- and sex-matched HC, were scanned on a 3T scanner. Phase-, T1-, and T2-lesion characteristics were determined. Overlap of T1- and T2-weighted imaging (WI) lesions with phase lesions (T1P and T2P), as well as brain atrophy outcomes, was assessed.
Results:
MS patients showed significantly greater numbers and larger volume of phase lesions, compared with HC (P < 0.001). 23.6% of T2 lesions overlapped with phase lesions, whereas the same figure for T1 lesions was 37.3%. Conversely, 33.4% and 69.7% of phase lesions were not visible on T2- or T1-WI, respectively. Phase, T1P and T2P lesions were not related to clinical outcomes, but phase lesions were related to ventricular enlargement.
Conclusion:
Phase lesions were present in both MS and CIS patients, and showed partial overlap with lesions observed using conventional MRI. The role of phase lesions in clinical progression remains unclear and should be further explored.
Insights
Susceptibility-weighted imaging (SWI)-filtered phase lesions are more prevalent in multiple sclerosis (MS) and clinically isolated syndrome (CIS) patients than healthy controls. These phase lesions partially overlap with conventional MRI lesions but their clinical significance requires further investigation.
Area of Science:
- Neuroimaging
- Radiology
- Neurology
Background:
- Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system.
- Susceptibility-weighted imaging (SWI) is a sensitive MRI technique for detecting paramagnetic substances like iron and deoxygenated blood.
- Phase lesions on SWI-filtered phase images represent a potential marker for MS pathology.
Purpose of the Study:
- To investigate the presence and characteristics of phase lesions in patients with MS, clinically isolated syndrome (CIS), and healthy controls (HC).
- To assess the overlap between phase lesions and conventional T1- and T2-weighted imaging (WI) lesions.
- To correlate phase lesion characteristics with clinical outcomes and brain atrophy.
Main Methods:
- A 3T MRI scanner was used to image 95 relapsing-remitting MS patients, 40 secondary-progressive MS patients, 19 CIS patients, and 49 age- and sex-matched HC.
- Phase-, T1-, and T2-lesion characteristics were quantified.
- Overlap analysis between phase lesions and T1/T2-WI lesions (T1P and T2P) was performed, along with assessment of brain atrophy.
Main Results:
- MS patients exhibited significantly higher numbers and volumes of phase lesions compared to HC (P < 0.001).
- 37.3% of T1 lesions and 23.6% of T2 lesions overlapped with phase lesions; conversely, 69.7% of phase lesions were not visible on T1-WI and 33.4% on T2-WI.
- Phase lesions, T1P, and T2P showed no relation to clinical outcomes but were associated with ventricular enlargement.
Conclusions:
- Phase lesions are detectable in both MS and CIS patients, demonstrating partial concordance with conventional MRI findings.
- A significant portion of phase lesions are not visualized by standard T1- and T2-weighted imaging.
- The clinical impact and role of phase lesions in disease progression warrant further research.
