title: Doppler ultrasound examination of multiple sclerosis patients and control participants: inter-observer agreement and association with disease.
abstract: OBJECTIVE
  Chronic cerebrospinal venous insufficiency (CCSVI) has been proposed as a major risk factor for multiple sclerosis (MS). The aim of this study was to assess inter-observer agreement between two ultrasound examiners and to compare findings in MS patients and control participants.
  
  
  METHODS
  A prospective, blinded, controlled study of MS patients diagnosed within 2 years (MS ≤ 2, n = 39), patients diagnosed more than 10 years ago (MS > 10, n = 43) and age- and sex-matched control participants (n = 40). Ultrasound examinations were performed by two independent examiners. CCSVI criteria 1, 3, 4 and 5 as proposed by Zamboni were explored: (1) reflux in the internal jugular (IJV) and vertebral veins (VV), (3) IJV cross-sectional area (CSA) ≤0.3 cm(2), (4) absence of flow in IJV and VV, and (5) reverted postural control of venous outflow.
  
  
  RESULTS
  Criteria 1, 4 and 5 were met in less than 10% of the MS patients and control participants as studied by both examiners. The level of inter-observer agreement was poor for all parameters except assessment of the CSA of IJV at the thyroid level. Findings meeting CCSVI criterion 3 (CSA ≤ 0.3 cm(2)) were observed in 18/40 (45%) of the control participants, in 24/37 (65%) of MS ≤ 2 patients (p = 0.09 vs. control participants) and in 30/43 (70%) of the MS > 10 patients (p = 0.022 vs. control participants).
  
  
  CONCLUSIONS
  The feasibility of the CCSVI criteria for common use is questionable because of low inter-observer agreement. Small-calibre IJVs meeting the CCSVI criterion 3 appear common in both Finnish control participants and MS patients, but the clinical significance of this finding is questionable.
authors.affiliation: Department of Vascular Surgery, Helsinki University Central Hospital, Helsinki, Finland. Electronic address: sani.laukontaus@hus.fi.
authors.forename: S J
authors.initials: SJ
authors.lastname: Laukontaus
authors.forename: T
authors.initials: T
authors.lastname: Kagayama
authors.forename: M
authors.initials: M
authors.lastname: Lepäntalo
authors.forename: S
authors.initials: S
authors.lastname: Atula
authors.forename: M
authors.initials: M
authors.lastname: Färkkilä
authors.forename: A
authors.initials: A
authors.lastname: Albäck
authors.forename: Y
authors.initials: Y
authors.lastname: Inoue
authors.forename: P
authors.initials: P
authors.lastname: Tienari
authors.forename: M
authors.initials: M
authors.lastname: Venermo
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D016009:Chi-Square Distribution; D002908:Chronic Disease; D005240:Feasibility Studies; D005260:Female; D005387:Finland; D006801:Humans; D007601:Jugular Veins / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015588:Observer Variation; D056888:Patient Positioning; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D013131:Spine / Q000098:blood supply*; D016683:Supine Position; D018608:Ultrasonography, Doppler; D014680:Veins / Q000000981:diagnostic imaging / Q000503:physiopathology; D014689:Venous Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055815:Young Adult
keywords: CCSVI; Doppler ultrasound; Internal jugular vein; Multiple sclerosis