title: Role of color-coded Doppler sonography in the assessment of internal ureteral stent patency.
abstract: OBJECTIVE
  To evaluate the role of color-coded Doppler sonography (CCDS) in the assessment of internal ureteral stent patency.
  
  
  METHODS
  We compared micturating cystography (MC) and CCDS in 48 patients with internal ureteral stents. Forty-five of these patients had pyelocaliectasis on renal sonography.
  
  
  RESULTS
  In all of the 48 patients, the distal end of the internal ureteral stent could be seen sonographically in the bladder. The color images of 30 patients showed typical flow from the distal holes of the stent. Micturating cystography demonstrated patency of the stents in 36 patients. The two procedures showed the same results in 42 of 48 patients. Six patients had no detectable flow by CCDS, but the MCs showed patency of the stents.
  
  
  CONCLUSIONS
  The CCDS is a valid noninvasive method for the assessment of internal ureteral stent patency with a sensitivity of 100%, a specificity of 83%, a positive predictive value of 67%, and a negative predictive value of 100%.
authors.affiliation: Department of Urology, University of Heidelberg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Haferkamp
authors.forename: D
authors.initials: D
authors.lastname: Brkovic
authors.forename: M
authors.initials: M
authors.lastname: Wiesel
authors.forename: G
authors.initials: G
authors.lastname: Staehler
authors.forename: J
authors.initials: J
authors.lastname: Dörsam
mesh_terms: D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015607:Stents; D018615:Ultrasonography, Doppler, Color; D014513:Ureter / Q000000981:diagnostic imaging*; D014554:Urination