A reliability study of colour-Doppler sonography for the diagnosis of chronic cerebrospinal venous insufficiency shows low inter-rater agreement.
OBJECTIVE
Chronic cerebrospinal venous insufficiency (CCSVI) has been extremely variable, associated with multiple sclerosis in colour-Doppler sonographic studies. We aimed to evaluate inter-rater agreement in a colour-Doppler sonography venous examination.


METHODS
Inter-rater agreement study.


METHODS
First-referral multiple sclerosis centre.


METHODS
38 patients with multiple sclerosis and 55 age-matched (±5 years) controls.


METHODS
Sonography was carried out in accordance with Zamboni's five criteria by eight sonographers with different expertise, blinded to the status of cases and controls. Each participant was evaluated by two operators.


METHODS
Inter-rater agreement was measured through the κ statistics and the intraclass correlation coefficient.


RESULTS
The agreement was no higher than chance for criterion 2-reflux in the deep cerebral veins (κ=-0.02) and criterion 4-flow not Doppler detectable in one or both the internal jugular veins (IJVs) or vertebral veins (VVs; -0.09). It was substantially low for criterion 1-reflux in the IJVs and/or VVs (0.29), criterion 3-IJV stenosis or malformations (0.23) and criterion 5-absence of IJV diameter increase when passing from the sitting to the supine position (0.22). The κ value for CCSVI as a whole was 0.20 (95% confidence limit -0.01 to 0.42). Intraclass correlation coefficients for the measure of cross-sectional area ranged from 0.05 to 0.25. Inter-rater agreement was low for CCSVI experts (κ=0.24; -0.11 to 0.59) and non-experts (0.20; -0.33 to 0.73); neurologists (0.21; -0.06 to 0.47) and non-neurologists (0.18; -0.20 to 0.56); cases (0.19; -0.14 to 0.52) and controls (0.21; -0.08 to 0.49). Zamboni-trained neurosonographers ascertained CCSVI more frequently than the non-trained neurosonographers.


CONCLUSIONS
Agreement was unsatisfactory for the diagnosis of CCSVI as a whole, for each of its five criteria and according to the different subgroups. Standardisation of the method is urgently needed prior to its further application in studies of patients with multiple sclerosis or other neurological diseases.
MS Centre, SCDU Neurology, Head and Neck Department, AOU 'Maggiore della Carità', Novara, Italy.
Maurizio A
MA
Leone
Olga
O
Raymkulova
Ausiliatrice
A
Lucenti
Alessandro
A
Stecco
Laura
L
Bolamperti
Lorenzo
L
Coppo
William
W
Liboni
Gianandrea
G
Rivadossi
Giuseppe
G
Zaccala
Maurizio
M
Maggio
Fabio
F
Melis
Claudia
C
Giaccone
Alessandro
A
Carriero
Piergiorgio
P
Lochner