Quantitative MRI findings indicate diffuse white matter damage in Susac Syndrome.

Area of Science:

• Neuroimaging
• Autoimmune Diseases
• Neurology

Background:

• Susac syndrome (SuS) is an autoimmune endotheliopathy affecting the brain, retina, and cochlea.
• SuS can clinically mimic multiple sclerosis (MS).

Purpose of the Study:

• To evaluate non-lesional white matter demyelination in SuS compared to MS and healthy controls (HC).
• Utilize quantitative MRI techniques for precise assessment.

Main Methods:

• Acquired 3T MRI data including myelin water imaging and diffusion basis spectrum imaging.
• Analyzed non-lesional white matter in the corpus callosum (CC) and normal-appearing white matter (NAWM).
• Compared groups using ANCOVA with Tukey correction.

Main Results:

• SuS corpus callosum (CC) showed lower myelin water fraction and increased radial diffusivity compared to MS and HC.
• Fractional anisotropy was lower in SuS CC compared to HC.
• Normal-appearing white matter (NAWM) in SuS exhibited significantly increased radial diffusivity and apparent diffusion coefficient versus HC and MS.

Conclusions:

• Evidence of myelin damage in SuS, particularly in the CC.
• More extensive microstructural injury observed in NAWM in SuS patients.
• Findings support widespread microstructural changes and diffuse demyelination in Susac syndrome.