When is the Radiologically Isolated Syndrome already Multiple Sclerosis According to the 2024 McDonald Criteria?

PURPOSE OF REVIEW: The McDonald criteria assist neurologists in making accurate and timely diagnoses of multiple sclerosis (MS). The 2024 revision of these criteria aims to enable a more timely diagnosis by including additional biomarkers and alternative diagnostic approaches. They also extend to individuals with MRI findings typical of multiple sclerosis that lack classic MS symptoms, as they would previously have been classified as having radiologically isolated syndrome (RIS). This review examines the scientific foundation of the novel biomarkers used and how the revised criteria influence individuals undergoing diagnostic evaluation, clinical practice, and society. RECENT FINDINGS: Most research concentrates on the scientific foundation for the updates rather than their impact. Benefits and potential disadvantages of the revised criteria can be identified for individuals undergoing diagnostic evaluation, clinical practice, and society. Additional guidelines for real-life application to guide management decisions are advisable.