Imaging the multiple sclerosis lesion: insights into pathogenesis, progression and repair

Area of Science:

• Neurology
• Radiology
• Neuroimaging

Background:

• Multiple sclerosis (MS) is characterized by focal white matter lesions.
• Understanding lesion pathophysiology traditionally relied on limited neuropathological data.
• Recent advances enable in-vivo study of MS lesion dynamics.

Purpose of the Study:

• To review current and emerging concepts of MRI-defined MS lesions.
• To explore advanced longitudinal imaging for dynamic microstructural change.
• To discuss emerging MRI measures of lesion repair.

Main Methods:

• Utilizing novel MRI techniques to study active and chronic MS lesions.
• Employing advanced diffusion imaging for longitudinal biomarker development.
• Integrating myelin-imaging techniques into clinical trials.

Main Results:

• MRI reveals dynamic features of active MS lesions.
• Imaging surrogates for chronic active lesions have been defined.
• Progressive microstructural changes in chronic inactive lesions are observed.
• In vivo unraveling of lesion-related neurodegenerative mechanisms via MRI.

Conclusions:

• MRI provides new insights into the MS lesion lifecycle.
• Focal pathology is a key determinant of MS disease progression.
• Longitudinal MRI biomarkers are vital for future neurorepair trials in MS.