40 patients with highly active MS (disease duration 6.5 years) defined by clinical criteria were enrolled before switching to highly effective DMD.These criteria were patients with 1 relapse in the previous year and at least 1 T1 Gd+ lesion or 9 or more T2 lesions, while on therapy with other DMDs. Patients with 2 or more relapses in the previous year, whether on DMD treatment or not.

MRI data were obtained from high resolution T1 sequences and post processed in collaboration with jung diagnostics GmbH by vote-wise morphometry using SPM 12.

The study was cross-sectional, controlled and not randomized. The data analysis was focused on BPV (Brain Parenchyme Volume) and thalamus volume, the region with highest sensitivity. Volume data were related to the disease duration, the first relapse defined as beginning of the disease.