Wei Tian1, Tong Zhu1, Jianhui Zhong1, Xiang Liu1, Praveen Rao2, Benjamin M. Segal2, Xiang Liu
1 Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, United States; 2University of Michigan
A longitudinal DTI study was performed in 11 SPMS patients who completed 6 bimonthly MRI scans in one year. Based on the presence of T1 enhancing lesions during the study period, patients were divided into enhancing and non-enhancing groups. The enhancing group showed progressive FA decrease in body and splenium of corpus callosum (CC), accompanied significant elevation of radial diffusivity, but no obvious axial diffusivity change. No obvious temporal change of eigenvalues and FA was found in CC in the non-enhancing group. These findings revealed that the body and splenium part of CC were more vulnerable to damage than genu in SPMS. The radial diffusivity increase may contribute to FA reduction of CC in active progression compared to a more stable stage of the disease. DTI eigenvalues can provide valuable parameters for evaluating the severity, monitoring progression non-invasively, and exploring pathological functional pathways of SPMS in the future.