The chronic involvement of the afferent visual system in multiple sclerosis (MS) is a powerful model to understand the temporal course and functional relevance of neurodegeneration because it is very well distinguishable from neighboring structures and offers quantifiable structural and functional metrics. Optical coherence tomography (OCT) of the retina and diffusion tensor imaging (DTI)-based tractography of the optic radiation have proven to provide sensitive markers for neurodegeneration of the visual pathway in MS.1,2 OCT-derived neuroaxonal retinal damage, represented by thinning of the retinal nerve fiber layer (RNFL) and ganglion cell/inner plexiform layer (GCIPL), has been reported in patients with MS with a history of optic neuritis (ON) and—to a lesser extent—also independent of ON episodes.1 RNFL and GCIPL show strong associations with visual function in MS, especially with low-contrast visual acuity.3 Both layer thicknesses are associated with brain atrophy: this association being stronger in the eyes without a history of ON.3