The reproducibility of colour Doppler in chronic cerebrospinal venous insufficiency associated with multiple sclerosis.

AIM: Chronic cerebrospinal venous insufficiency (CCSVI) is a syndrome described in multiple sclerosis (MS) patients, characterized by stenosis of the main extracranial veins with hampered cerebral venous outflow. In the original description echo-colour Doppler demonstrated to be an ideal non invasive tool for screening CCSVI patients, but the reproducibility was not assessed. Aim of this study is to assess the variability coefficient between trained and in not trained echo-colour Doppler operators.
METHODS: Thirty-six (36) subjects, matched for age and gender, were subset in 3 groups (group A, 12 healthy controls, HC; group B, 12 multiple sclerosis patients, MS; group C, 12 patients with other neurological disease, OND) underwent echo-colour Doppler screening for CCSVI according to an original protocol previously described. The inter observer variability rate was assessed by comparing respectively trained vs not trained operators, and trained vs trained operators, by using the same echo-colour Doppler equipment. In addition, by scanning 15 subjects after one month from the first session, intra observer coefficient was also assessed in trained operator.
RESULTS: The inter observer variability rate between trained and not trained echo-colour Doppler operators, were not completely satisfactory (K coefficient 0.47 95% CI 0.27-0.68). To the contrary the inter observer agreement between trained operators was much more reliable (K coefficient 0.80 95% CI 0.59-1.01). Finally, the intra observer variability rate in trained operators was 0.93, (95% CI 0.80-1.06) confirming a highly satisfactory agreement.
CONCLUSION: Echo-colour Doppler is a powerful, non-invasive and reproducible tool for screening CCSVI-MS but it needs special training.