MRI analysis of the "central vein sign" allows identification of a subset of relapsing remitting MS patients with brain pathology different from inflammatory demyelination

The central vein sign is a brain MRI marker that can distinguish multiple sclerosis (MS) from MS mimickers. The threshold of CVS-frequency (CVS-f) that allows the exclusion of MS has so far been established as CVS-f<50% (“50%-rule”). As MS misdiagnosis is estimated around 10%, aim of this study is to evaluate if the 50%-rule can identify subgroups of MS-diagnosed patients with underlying pathology suggesting alternative diagnosis. Conclusions: A group of MS-plus patients not fulfilling the 50% rule can be identified with high specificity by FLAIR* sequences with single conventional MRI scan. In these patients an underlying pathology alternative to the inflammatory-demyelinating one was observed and therefore a diagnosis alternative to MS should be considered.