Hippocampal Magnetization Transfer Ratio and Not Hippocampal Atrophy Best Explains Memory Dysfunction in Patients with Multiple Sclerosis

Mishkin Derakhshan¹, Gabriel Leonard¹, Daviad Araujo¹, D. Louis Collins¹, Douglas L. Arnold¹, Sridar Narayanan¹

The hippocampi (HC) have been found to be demyelinated in postmortem studies of patients with multiple sclerosis (MS), and HC pathology has been shown to be responsible for memory impairment. Using magnetization transfer ratio (MTR) as a marker of demyelination, we examined HC demyelination and HC atrophy in 26 patients with MS and 15 controls matched for age, sex, and education level. We found that focal HC MTR values best explained memory performance, specifically working and visual immediate memory, better than volumetric measures.