The radiologically isolated syndrome

Neurologists frequently consult on patients who have had asymptomatic white matter T2 hyperintensities discovered incidentally on brain MRI. The consult often comes with the question “Does this person have multiple sclerosis (MS)?” Usually the patient has nothing clinically to indicate MS, the pattern of white matter changes is not suggestive of MS, and the T2 hyperintensities can be attributed to another cause.1 However, occasionally the patient has no signs or symptoms of MS but the appearance of the white matter abnormalities on MRI are highly suggestive of MS. What is our diagnosis for such patients and do we treat them for MS? In this issue of Neurology ®, Okuda et al.2 describe a cohort of subjects who had an initial brain MRI highly suggestive of MS but no signs or symptoms of the illness. They propose calling this condition the radiologically isolated syndrome (RIS). The cohort consisted of 44 individuals. All had a baseline brain MRI with ovoid foci of white matter T2 hyperintensities and met at least three of four of the Barkhof criteria …