Major Update Incorporates Optic Nerve in Multiple Sclerosis Diagnostic Criteria

The international medical community has announced a significant revision to the diagnostic criteria for multiple sclerosis (MS), now including the optic nerve as a key anatomical site for disease dissemination. This update results from a comprehensive consensus process led by the International Advisory Committee on Clinical Trials, aimed at integrating recent advances in imaging technology and biomarker research. Previously, MS diagnosis relied on evidence of lesions in various locations over time, with a focus on MRI, cerebrospinal fluid (CSF) analysis, and clinical manifestations.

The new criteria recognize the optic nerve as a fifth site where lesions can support MS diagnosis, alongside the brain, spinal cord, cerebellum, and brainstem. This change allows clinicians to establish dissemination in space more effectively, especially when lesions are detected in at least two regions, whether symptomatic or not. Notably, in cases with lesions in only one location, positive findings from optical coherence tomography (OCT), visual evoked potentials (VEP), MRI, or the central vein sign—particularly using the select-6 method—can suffice for diagnosis, especially when combined with CSF biomarkers such as kappa free light chain or oligoclonal bands.

Dissemination in time remains a criterion but is now less obligatory in certain scenarios. The presence of new or simultaneous enhancing and non-enhancing lesions continues to improve diagnostic specificity. Additionally, paramagnetic rim lesions and the central vein sign contribute to increased accuracy, with these features being pivotal in distinguishing MS from other conditions.

The revised guidelines also facilitate diagnosis of both pediatric and adult-onset MS, as well as relapsing and progressive forms. For individuals over 50 or with significant vascular risk factors, additional testing—such as spinal cord imaging, CSF analysis, or central vein sign assessment—is recommended to minimize misdiagnosis. Ultimately, these updates aim to streamline diagnosis, promote earlier intervention, and incorporate accessible tools, thereby improving patient outcomes and supporting a unified biological understanding of MS.