The contribution of assessing cognitive impairment in radiologically-isolated syndrome (RIS): a single case report follow-up study.

Radiologically-isolated syndrome (RIS) is a recently-defined entity, described as the incidental discovery of lesions suggestive of multiple sclerosis (MS) on brain magnetic resonance imaging (MRI) scans demonstrating dissemination in space (DIS) without symptom expression and with a normal neurological examination. Recent studies demonstrate that RIS patients present similar features of cognitive impairment as MS patients. We describe a case of a RIS patient in whom investigating cognitive functions was a useful tool for diagnostic and therapeutic decisions.