Optic nerve region in multiple sclerosis diagnosis: the utility of visual evoked potentials

Objective: To assess the added value of the optic nerve region (by using visual evoked potentials-VEPs-) to the current diagnostic criteria. Methods: From the Barcelona clinically isolated syndrome (CIS) cohort, patients with complete information to assess dissemination in space (DIS), the optic nerve region, and dissemination in time (DIT) at baseline (n=388) were selected. Modified DIS (modDIS) criteria were constructed by adding the optic nerve to the current DIS regions. The DIS and modDIS criteria were evaluated using univariable Cox proportional hazard regression analyses using the time to the second attack as the outcome. A subset of these patients who had at least 10 years of follow-up or a second attack occurring within 10 years (n=151) were selected to assess the diagnostic performance. The analyses were also performed according to CIS topography (optic neuritis vs non-optic neuritis). Results: The addition of the optic nerve as a fifth region improved the diagnostic performance by slightly increasing the accuracy (2017 DIS: 75.5%, modDIS: 78.1%) and the sensitivity (2017 DIS: 79.2%, modDIS: 82.3%), without lowering the specificity (2017 DIS: 52.4%, modDIS: 52.4%). When the analysis was conducted according to CIS topography, the modDIS criteria performed similarly in both optic neuritis and non-optic neuritis CIS. Conclusion: The addition of the optic nerve, assessed by VEP, as a fifth region in the current DIS criteria slightly improve the diagnostic performance as it increases sensitivity without losing specificity.