Multiple sclerosis (MS) is the leading disease within the field of neuroimmunology, affecting >2.8 million people worldwide (Jakimovski et al., 2024). Since the first descriptions by Jean-Martin Charcot in the 19th century, substantial progress has been made in understanding this complex disorder (Agrawal et al., 2025). In the second half of the 20th century, the Schumacher criteria (1965) were introduced, establishing the concept of dissemination in time. Later, the Poser criteria (1985) incorporated laboratory support through cerebrospinal fluid (CSF) analysis and visual evoked potentials (Agrawal et al., 2025).

With the advent of the 21st century came widespread access to brain magnetic resonance imaging (MRI). The 2001 McDonald criteria represented a major milestone by incorporating MRI to demonstrate dissemination in space—across the four classical topographies (periventricular, juxtacortical, infratentorial, and spinal cord)—and dissemination in time, defined by the appearance of new T2 lesions or the simultaneous presence of enhancing and non-enhancing lesions. The McDonald criteria were subsequently revised in 2005, 2010, and 2017, each update refining diagnostic accuracy and integrating advances in imaging and biomarkers (Jakimovski et al., 2024; Agrawal et al., 2025).