Massimo Filippi, MD, Vita-Salute San Raffaele University, Milan, Italy, discusses possible future changes to the 2017 McDonald criteria for the diagnosis of multiple sclerosis (MS). First, the optic nerve may be added as a potential lesion site to qualify for MS diagnosis; the optic nerve is affected in over 90% of MS patients. In addition, to maintain disease specificity, the number of lesions in the periventricular area required to qualify for periventricular involvement may be increased from 1 to 3. Lastly, lesions with a central vein sign (CVS) may be incorporated into the criteria; the proportion of CVS lesions in MS patients is over 40-50%, much greater than in mimicking conditions. This interview took place during the European Academy of Neurology 2021 congress.