title: Hemodialysis access imaging: comparison of flow-interrupted contrast-enhanced MR angiography and digital subtraction angiography.
abstract: OBJECTIVE
  To compare flow-interrupted contrast material-enhanced magnetic resonance (MR) angiography with conventional digital subtraction angiography (DSA) for hemodialysis access imaging.
  
  
  METHODS
  Twenty-two accesses (14 arteriovenous grafts [AVGs], eight arteriovenous fistulas [AVFs]) in 18 consecutive patients were imaged with flow-interrupted contrast-enhanced MR angiography and subsequent conventional DSA. MR image quality was assessed as excellent, good, or nondiagnostic. Anastomotic diameters in AVGs and postanastomotic diameters in AVFs were measured in consideration of an adjacent normal segment. Reductions in the diameter of the lumen and interobserver differences were analyzed with method comparison as described by Bland and Altman and expressed as the mean difference with its 95% confidence limits (CLs) (mean +/- 2 SDs).
  
  
  RESULTS
  Image quality obtained with flow-interrupted contrast-enhanced MR angiography was considered excellent in 73% (16 of 22) and good in 23% (5 of 22). Method comparison analysis between MR angiography and DSA indicated a mean difference of 3.2% (95% CLs: -26.7%, 33.1%) for observer 1 and 4.1% (95% CLs: -23.8%, 32.1%) for observer 2. Interobserver analysis at MR angiography indicated a mean difference of 3.2% (95% CLs: -28.8%, 35.2%), and that at DSA indicated a mean difference of 3.6% (95% CLs: -9.4%, 16.7%).
  
  
  CONCLUSIONS
  Image quality and anatomic depiction with flow-interrupted contrast-enhanced MR angiography and with DSA were comparable.
authors.affiliation: Department of Nephrology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands.
authors.forename: Johannes H M
authors.initials: JH
authors.lastname: Smits
authors.forename: Clemens
authors.initials: C
authors.lastname: Bos
authors.forename: Otto E H
authors.initials: OE
authors.lastname: Elgersma
authors.forename: Wil A M A
authors.initials: WA
authors.lastname: van der Mark
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Blankestijn
authors.forename: Chris J G
authors.initials: CJ
authors.lastname: Bakker
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Zijlstra
authors.forename: Sandra
authors.initials: S
authors.lastname: Kalmijn
authors.forename: Willem P T M
authors.initials: WP
authors.lastname: Mali
mesh_terms: D015901:Angiography, Digital Subtraction; D001166:Arteriovenous Shunt, Surgical; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA