Subcortical Deep Gray Matter Pathology in Patients with Multiple Sclerosis Is Associated with White Matter Lesion Burden and Atrophy but Not with Cortical Atrophy: A Diffusion Tensor MRI Study ================================================================================================================================================================================================ * R. Cappellani * N. Bergsland * B. Weinstock-Guttman * C. Kennedy * E. Carl * D.P. Ramasamy * J. Hagemeier * M.G. Dwyer * F. Patti * R. Zivadinov