| Abstrakt: |
Background: Absence of clinical and MRI activity are accepted as paradigms of "disease-free" status in multiple sclerosis (MS) treated patients. Clinical activity is defined by no relapses and EDSS progression, and MRI activity by no T1W contrast enhancing lesions as well as no new or enlarging T2W lesions. Previous studies have shown that axonal loss progression may occur whilst lacking clinical and imaging expression, requiring more sophisticated MRI techniques. Our study discusses the current concept of "disease-free", proposing that axonal loss be used as a practical tool for defining optimal treatment Objectives: To investigate if axonal loss, an early finding in MS that relates to disability, can be used as a marker to optimize treatment. Methods: We prospectively studied a cohort of 191 consecutive, non-selected patients with relapsing-remitting MS, diagnosed according to the McDonald 2001 criteria, on regular immunomodulatory treatment. They were submitted to serial clinical examinations and conventional MRI evaluation with a focus on relapses, EDSS progression and the presence of T1W Gd-enhancing or T2W new/enlarged lesions. On conventional MRI sequences, we studied whole brain and callosal atrophy, using brain parenchymal fraction (BPF) and corpus callosum index (CCI). Results were compared annually with data from a control group composed of other neurological non-inflammatory diseases, as well as data from our historical series of secondary progressive MS patients Results: Among these 191 patients, 89 (46.5%) experienced neither relapses nor sustained progression on the EDSS, and no evidence of active MRI lesions after 5-years, thus fulfilling the proposed criteria for disease-free status. Nevertheless, 43/89 (48.3%) showed a progressive reduction in BPF and CCI, comparable with those stratified as suboptimal responders, and some of them reaching scores comparable to patients with progressive MS Conclusions: Our data demonstrate that axonal loss can be detected early and followed using a practical method of conventional MRI sequences. We suggest that this parameter be included as a requirement for the "disease-free" patient concept. [ABSTRACT FROM AUTHOR] |
