title: Multislice CT angiography in renal artery stent evaluation: prospective comparison with intra-arterial digital subtraction angiography.
abstract: OBJECTIVE
  To assess the role of multislice computed tomography angiography (MCTA) in the evaluation of renal artery stents, using intra-arterial digital subtraction angiography (DSA) as the gold standard.
  
  
  METHODS
  Twenty consecutive patients (15 men, 5 women) with 23 renal artery stents prospectively underwent both MCTA and DSA. Axial images, multiplanar reconstructions and maximum intensity projection images were used for diagnosis. The MCTA and DSA images were each interpreted without reference to the result of the other investigation.
  
  
  RESULTS
  The three cases of restenosis on DSA were detected correctly by MCTA; in 19 cases where MCTA showed a fully patent stent, the DSA was also negative. Sensitivity and negative predictive value (NPV) of MCTA were therefore 100%. In four cases, MCTA showed apparently minimal disease which was not shown on DSA. These cases are taken as false positive giving a specificity of 80% and a positive predictive value of 43%.
  
  
  CONCLUSIONS
  The high sensitivity and NPV suggest MCTA may be useful as a noninvasive screen for renal artery stent restenosis. MCTA detected mild disease in a few patients which was not confirmed on angiography.
authors.affiliation: Department of Radiology, St. Mary's Hospital, Praed Street, London W2 1NY, UK.
authors.forename: Syed A
authors.initials: SA
authors.lastname: Raza
authors.forename: Aamer R
authors.initials: AR
authors.lastname: Chughtai
authors.forename: Mona
authors.initials: M
authors.lastname: Wahba
authors.forename: Mark G
authors.initials: MG
authors.lastname: Cowling
authors.forename: David
authors.initials: D
authors.lastname: Taube
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Wright
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D019917:Blood Vessel Prosthesis Implantation; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012077:Renal Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency / Q000502:physiology