Analysis of Normal-Appearing White Matter in Multiple Sclerosis: Comparison of Diffusion Tensor MR Imaging and Magnetization Transfer Imaging

Our purpose was to compare diffusion tensor MR and magnetization transfer imaging in assessing normal-appearing white matter (WM) regions in multiple sclerosis (MS). Diffusion tensor, magnetization transfer, and conventional MR imaging were performed in 12 patients with MS. Fractional anisotropy, apparent diffusion coefficients (ADCs), and magnetization transfer ratios (MTRs) were measured in plaques, normal-appearing periplaque WM (PWM) regions, and normal-appearing WM regions remote from plaques. Mean fractional anisotropy, ADCs, and MTRs were calculated and compared in WM regions. Fractional anisotropy was lower in normal-appearing PWM regions than in remote WM regions (P