title: Potential role of duplex Doppler sonography in acute renal colic.
abstract: OBJECTIVE
  We assessed the value of renal duplex Doppler sonography in diagnosing obstruction in patients with acute renal colic.
  
  
  METHODS
  We compared the results of renal duplex Doppler sonography with those of intravenous urography (IVU) in 65 patients presenting with symptoms of renal colic. The Doppler spectral waveforms were used to calculate the resistance index (RI). The difference between the mean RIs (delta RI) in the 2 kidneys was calculated for each patient. The sensitivity, specificity, and accuracy of delta RI for the diagnosis of obstruction were calculated with several discriminatory thresholds.
  
  
  RESULTS
  All patients had an obstruction on IVU. When a high delta RI threshold for obstruction (delta RI > or = 0.1) was applied, the sensitivity and specificity of duplex Doppler sonography were 10% and 80%, respectively. When the delta RI threshold was decreased, the sensitivity increased but the specificity decreased, and both remained quite low. Twelve patients had a lower mean RI in the obstructed kidney than in the normal contralateral kidney. Among 14 patients without pyelocaliceal dilatation, the sensitivity of duplex Doppler sonography was 70% with a delta RI threshold of 0.03.
  
  
  CONCLUSIONS
  Duplex Doppler sonography is not sensitive enough to diagnose obstruction in patients with acute renal colic.
authors.affiliation: Department of Radiology B, Les Hôpitaux Universitaires de Strasbourg, Hôpital Civil, France.
authors.forename: C
authors.initials: C
authors.lastname: Roy
authors.forename: C
authors.initials: C
authors.lastname: Tuchmann
authors.forename: D
authors.initials: D
authors.lastname: Pfleger
authors.forename: S
authors.initials: S
authors.lastname: Guth
authors.forename: C
authors.initials: C
authors.lastname: Saussine
authors.forename: D
authors.initials: D
authors.lastname: Jacqmin
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity; D003085:Colic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000503:physiopathology; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006801:Humans; D007668:Kidney / Q000098:blood supply; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012077:Renal Artery / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018616:Ultrasonography, Doppler, Duplex