Optic nerve assessment identifies biomarkers of axonal pathology in multiple sclerosis

Our aim was to identify possible correlations between physical disabilities assessed by expanded disability status score (EDSS) and neurodegenerative process measured by retinal nerve fibers thickness, and also with demyelization process measured by visual evoked potential with P100 wave latency at optic nerve level on patients diagnosed with multiple sclerosis (MS). This study aimed to find a structural biomarker at central nerve system (CNS) level which could correlate with clinical disability. The optic nerve is an accessible structure of CNS easy to investigate. We analyzed a population of 111 patients diagnosed with different clinical forms of multiple sclerosis based on 2005 revised Mc Donald criteria, for whom we assessed clinical disability by EDSS, and by different subscales of multiple sclerosis composite (MSFC) as timed to walk 25 foot (TW25F) and nine hole peg test (9HPT). Optic nerve involvement was assessed for each eye measuring visual acuity (VA) (Snellen chart), P100 wave latency by visual evoked potential (VEP) and retinal nerve fiber layer thickness (RNFL) by optical coherence tomography (OCT). The medium age of our population was 38.09 and the medium EDSS was 3.