An impaired cerebrospinal venous drainage, defined as chronic cerebrospinal venous insufficiency (CCSVI), has been recently hypothesized to be the possible cause of multiple sclerosis (MS). We investigated this hypothesis by studying the occurrence of CCSVI in clinically isolated syndromes (CISs) suggestive of MS.


Fifty consecutive patients presenting with a CIS and evidence of dissemination in space of the inflammatory lesions (ie, possible MS [pMS]) underwent a detailed diagnostic workup, including extracranial and transcranial venous echo-color Doppler sonography (ECDS-TCDS). Those with CCSVI underwent selective venography. Fifty healthy subjects (HCs) age-matched and gender-matched with pMS patients (HC1); 60 patients with transient global amnesia (TGA); and 60 healthy subjects age-matched and gender-matched with TGA patients (HC2) constituted the control groups and underwent ECDS-TCDS.


Mean age of pMS patients was 33.0 ± 8.5 years (range, 14–50); 35 (70%) were female (female:male ratio, 2.3). TCDS was normal in all pMS patients. One or more abnormal ECDS findings were observed in 26 of 50 (52.0%) pMS patients, in 35 of 110 (31·8%) HCs (HC1+HC2), and in 41 of 60 (68.3%) TGA patients. Eight (16%) pMS patients fulfilled the diagnosis of CCSVI. Selective phlebography performed in 7 of these patients (1 denied consent) did not show venous anomalies.


Our findings do not support a cause-effect relationship between CCSVI and pMS. Further studies are warranted to clarify whether CCSVI is associated with later disease stages and characterizes the progressive forms of MS. Ann Neurol 2011;69:90–99.