title: Power and color Doppler ultrasound settings for inflammatory flow: impact on scoring of disease activity in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints.
  
  
  METHODS
  Six different types of ultrasound machines were used. On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity.
  
  
  RESULTS
  Power Doppler was more sensitive on half of the machines, whereas color Doppler was more sensitive on the other half, using both factory settings and study settings. There was an average increase in Doppler sensitivity, despite modality, of 78% when study settings were applied. Over the 6 machines, 2 Doppler modalities, and 2 settings, the grades for each of 7 of the patients varied between 0 and 3, while the grades for each of the other 4 patients varied between 0 and 2.
  
  
  CONCLUSIONS
  The effect of using different machines, Doppler modalities, and settings has a considerable influence on the quantification of inflammation by ultrasound in RA patients, and this must be taken into account in multicenter studies.
authors.affiliation: Copenhagen University Hospital, Frederiksberg, Denmark, and Copenhagen University Hospital at Glostrup, Glostrup, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Torp-Pedersen
authors.forename: Robin
authors.initials: R
authors.lastname: Christensen
authors.forename: Marcin
authors.initials: M
authors.lastname: Szkudlarek
authors.forename: Karen
authors.initials: K
authors.lastname: Ellegaard
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: D'Agostino
authors.forename: Annamaria
authors.initials: A
authors.lastname: Iagnocco
authors.forename: Esperanza
authors.initials: E
authors.lastname: Naredo
authors.forename: Peter
authors.initials: P
authors.lastname: Balint
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wakefield
authors.forename: Arendse
authors.initials: A
authors.lastname: Torp-Pedersen
authors.forename: Lene
authors.initials: L
authors.lastname: Terslev
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D006801:Humans; D007249:Inflammation / Q000175:diagnosis / Q000000981:diagnostic imaging; D009141:Musculoskeletal System / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018615:Ultrasonography, Doppler, Color / Q000295:instrumentation / Q000379:methods*; D014955:Wrist Joint / Q000000981:diagnostic imaging