Our understanding of radiologically isolated syndrome (RIS) is evolving, as new data emerge on the clinical characterization and the pathophysiological nature of this rare entity. This topical review aims to (1) outline state-of-the-art clinical and magnetic resonance imaging findings of RIS research; (2) raise the main obstacles to RIS research; (3) discuss the most controversial issues of current RIS findings; and (4) highlight potential strategies for upcoming research studies.
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