McDonald Criteria for the Diagnosis of Multiple Sclerosis
The McDonald criteria are the framework for diagnosing multiple sclerosis, integrating clinical attacks, MRI, and laboratory findings around the twin ideas of dissemination in space and in time. The 2024 revision is a substantial update aimed at faster, more specific diagnosis: the optic nerve becomes a fifth anatomical site for dissemination in space; the central vein sign and paramagnetic rim lesions are recognized as optional MRI markers on susceptibility-sensitive sequences; kappa free light chains join CSF oligoclonal bands as a substitute for dissemination in time; and, in defined situations, radiologically isolated syndrome can now meet the bar for MS. Stricter thresholds are applied in older patients and those with vascular risk factors to guard against misdiagnosis. Pair naturally with the MAGNIMS consensus as its imaging-focused companion.
Published in The Lancet Neurology (Sept 2025). Adds the optic nerve as a fifth dissemination-in-space site; recognizes the central vein sign and paramagnetic rim lesions as optional MRI markers; lets kappa free light chains substitute for dissemination in time; and, in defined situations, allows radiologically isolated syndrome to meet the bar for MS — with stricter thresholds in older / vascular-risk patients to curb misdiagnosis.
Let CSF oligoclonal bands substitute for dissemination in time and simplified the space/time rules, enabling earlier and more practical diagnosis.
Streamlined the MRI criteria so dissemination in space and time could be shown on a single scan, markedly speeding diagnosis.
Refined the imaging rules for dissemination in time and clarified the role of spinal-cord lesions.
Introduced the McDonald framework, formally integrating clinical, MRI and CSF findings around dissemination in space and in time.
Radiology Assistant publishes "Multiple Sclerosis 3.0," an updated educational review of MRI findings in MS, covering diagnostic criteria, differential diagnosis, and monitoring recommendations.
RadPigeon is an independent radiology news digest and is not affiliated with or endorsed by International Advisory Committee on Clinical Trials in MS. “McDonald criteria” is a trademark of its owner and is named here only to refer to the system. Always consult the official source for the exact, current criteria.