title: [Blood flow quantification in hemodialysis shunts by phase contrast magnetic resonance angiography (PC-MRA) compared with duplex sonography].
abstract: OBJECTIVE
  Aim of this study was to evaluate whether phase contrast MR angiography (PC-MRA) could provide additional functional information besides morphology in the assessment of haemodialysis fistulae.
  
  
  METHODS
  Twenty-two patients (11 male, 11 female), aged 22-77 years, were examined. MR images were obtained with a 1.5 T Gyroscan ACS-NT (Philips, Best, Netherlands) using a high-resolution wrap-around coil. In addition to MRA blood-flow measurements were performed with a gradient-echo sequence (TR 14 ms, TE 5-5.5 ms, flip-angle 15 degrees, 6 mm slice thickness, retrospective gating, matrix 96:128) in the venous and arterial section of the fistulae. Doppler flow measurements were performed at the same position with a Sonoline Elegra (Siemens AG, Erlangen) using a 7.5 MHz transducer.
  
  
  RESULTS
  Both methods of flow-volume measurements showed a good correlation (r = 0.94 in the arterial section, r = 0.90 in the venous section, p < 0.001). The average calculated blood flow was measured 11% (arterial section) and 12.8% (venous section) higher with Pulsed Waved Doppler as compared to PC-MRA.
  
  
  CONCLUSIONS
  PC-MRA with a high-resolution wrap-around coil is a reliable method for measuring functional parameters like flow-volume and flow velocity in haemodialysis fistulae and a useful complement to the visualisation capabilities of MRA.
authors.affiliation: Strahlenklinik und Poliklinik, Charité, Medizinische Fakultät der Humboldt-Universität Berlin.
authors.forename: M
authors.initials: M
authors.lastname: Gutberlet
authors.forename: S
authors.initials: S
authors.lastname: Venz
authors.forename: A
authors.initials: A
authors.lastname: Kahl
authors.forename: T
authors.initials: T
authors.lastname: Ehrenstein
authors.forename: R
authors.initials: R
authors.lastname: Puls
authors.forename: N
authors.initials: N
authors.lastname: Hosten
authors.forename: U
authors.initials: U
authors.lastname: Frei
authors.forename: R
authors.initials: R
authors.lastname: Felix
mesh_terms: D000328:Adult; D000368:Aged; D000714:Anastomosis, Surgical; D001783:Blood Flow Velocity; D005260:Female; D005402:Fistula; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D006435:Renal Dialysis; D015203:Reproducibility of Results; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods*