title: Accuracy of colour duplex sonography for the diagnosis of renal artery stenosis.
abstract: OBJECTIVE
  To examine the diagnostic value of novel velocimetric colour duplex sonography indices in the screening of renal artery stenosis (RAS).
  
  
  METHODS
  We performed a retrospective analysis of all consecutively studied patients at our centre with suspected RAS, and a colour duplex sonography carried out at less than 4 months (mean 34 days) before renal angiography during a 6-year period (2002-2007). A significant RAS was defined as an at least 60% stenosis on angiography or a transstenotic mean arterial pressure gradient of at least 10 mmHg or both.
  
  
  RESULTS
  In a total of 169 patients, 111 stenotic and 206 nonstenotic kidneys were examined. The sensitivity and specificity for acceleration of blood flow in early systole (ACCmax) were 85 and 75%, respectively, and for the acceleration index (ACCmax/peak systolic velocity, AImax) 83 and 79%, respectively. Corresponding values in patients with estimated glomerular filtration rate of less than 30 ml/min/1.73 m2 were 90 and 73% (for ACCmax) and 74 and 88% (for AImax). In addition, the transstenotic mean arterial pressure gradient showed a significant, though weak, negative correlation to ACCmax (r = -0.26, P = 0.02) and AImax (r = -0.29, P = 0.01) in stenotic kidneys.
  
  
  CONCLUSIONS
  ACCmax and AImax provide similar, good diagnostic accuracy in the detection of a haemodynamically significant RAS, even in patients with markedly reduced glomerular filtration rate. Presumably, the lack of superiority of the novel index AImax could be explained by a highly homogenous methodological approach in the present single-centre study.
authors: Department of Molecular and Clinical Medicine/Nephrology, Institute of Medicine, The Sahlgrenska Academy at the University of Gothenburg, Vita Stråket 12, Sahlgrenska University Hospital, Göteborg S-413 45, Sweden. aso.saeed@vgregion.se
authors: Aso
authors: A
authors: Saeed
authors: Göran
authors: G
authors: Bergström
authors: Karin
authors: K
authors: Zachrisson
authors: Gregor
authors: G
authors: Guron
authors: Elzbieta
authors: E
authors: Nowakowska-Fortuna
authors: Ellen
authors: E
authors: Fredriksen
authors: Lars
authors: L
authors: Lönn
authors: Gert
authors: G
authors: Jensen
authors: Hans
authors: H
authors: Herlitz
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012189:Retrospective Studies; D013599:Systole; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods*