Anomalies Characteristic of Central Nervous System Demyelination: Radiologically Isolated Syndrome

Radiologically isolated syndrome (RIS) was defined in 2009 for asymptomatic patients who presented incidentally identified white matter anomalies within the central nervous system suggestive of multiple sclerosis (MS). Approximately one-third of RIS subjects will have a seminal clinical demyelinating event within 5 years of the identification of their abnormal MRI. Clinical evolution mirrors relapsing remitting or progressive forms of MS. Pejorative factors for clinical conversion are male gender, age younger than 35 years, and spinal cord lesions.