Quantify oxidative stress and iron via kex MRI and QSM for differential diagnosis of multiple sclerosis and cerebral small vessel diseases.

Motivation: Challenges arise in differentiating multiple sclerosis(MS) and cerebral small vessel disease(SVD) using conventional MRI. Goal(s): Assess k ex MRI & QSM utility in differentiating MS from SVD in vivo. Approach: This IRB-approved retro study enrolled 47 MS, 31 SVD pts, and 25 HCs, undergoing kex MRI & QSM. Susceptibility & kex values were compared among MS-WMLs, SVD lacunes, & WMHs, with ROC analysis. Results: Significant susceptibility and kex increases seen only in MS-WMLs. WMHs show mild kex increase, lacunes similar susceptibility but lower kex. Positive correlation between kex and susceptibility increases only in MS-WMLs. Combined kex and susceptibility values improve diagnostic accuracy in differentiating MS-WMLs, WMHs, and lacunes. Impact: The in vivo visualization and quantification of oxidative stress and iron deposition via kex MRI and QSM are the potential biomarkers to promote the early differential diagnosis of MS and SVD.