Retinal axonal loss in very early stages of multiple sclerosis

Background and purpose The lack of surrogates of clinical progression has limited the design of neuroprotection trials in multiple sclerosis (MS). Our aim was to study the association between time-domain optical coherence tomography measures and clinical and magnetic resonance imaging outcomes in early MS. Methods Forty-three relapsing−remitting MS patients within 1 year of onset were followed for up to 3 years. Results The peripapillary retinal nerve fiber layer (RNFL) decreased annually by 2 μm (95% confidence interval −3.89, −0.11; P = 0.038). The RNFL tended to be associated with normalized normal appearing white matter volume in cross-sectional (P = 0.08) and longitudinal analyses (P = 0.06). Conclusions There is substantial RNFL loss even in very early MS. Our data suggest that retinal axonal atrophy is associated with atrophy in global white matter volume in early MS.