title: Evaluation of disease activity in ankylosing spondylitis; diagnostic value of color Doppler ultrasonography.
abstract: BACKGROUND
  Spondyloarthropathies including ankylosing spondylitis (AS) require early diagnosis to prevent irreversible changes. Sacroiliitis is a common initial manifestation of AS and is frequently diagnosed by magnetic resonance imaging (MRI). The goal of our study was to assess color Doppler ultrasonography as a potential diagnostic tool in suspected sacroiliitis in comparison with MRI representing the gold standard.
  
  
  METHODS
  Fifty-one consecutive patients with AS and sacroiliitis and 30 control subjects underwent contrast-enhanced MRI and high resolution color Doppler and duplex ultrasonography of both sacroiliac joints (SIJ) for the detection of vascularization and blood flow spectral Doppler waveform analysis.
  
  
  RESULTS
  MRI demonstrated active disease in 27 and inactive disease in 24 patients. CDUS detected pulsatile monophasic wave spectral waveform flow in 22 patients with the active disease, and triphasic in 7 patients with inactive disease and in 8 control patients. The sensitivity, specificity, positive predictive value and negative predictive value for active sacroiliitis detection with CDUS were 82 % (95 % CI, 68-91 %), 92 % (95 % CI, 85-96 %), 91 % (95 % CI, 84-96 %), and 84 % (95 % CI, 70-92 %), respectively, for pulsatile monophasic wave spectral waveform Doppler sonography. MRI of SIJ was negative in all 30 (60 SIJ) control participants.
  
  
  CONCLUSIONS
  Our results show that CDUS is a practical and useful tool in the diagnosis of active sacroiliitis.
authors.affiliation: Department of Radiology, Urmia University of Medical Sciences, Urmia, West-Azerbaijan, Iran. mohamadi_afshin@yahoo.com
authors.forename: Afshin
authors.initials: A
authors.lastname: Mohammadi
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghasemi-rad
authors.forename: Miramir
authors.initials: M
authors.lastname: Aghdashi
authors.forename: Nikol
authors.initials: N
authors.lastname: Mladkova
authors.forename: Paria
authors.initials: P
authors.lastname: Baradaransafa
mesh_terms: D000465:Algorithms; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D058566:Sacroiliitis / Q000150:complications* / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000150:complications* / Q000175:diagnosis*; D018615:Ultrasonography, Doppler, Color / Q000379:methods*