title: Renal artery stenosis: grading of hemodynamic changes with cine phase-contrast MR blood flow measurements.
abstract: OBJECTIVE
  To analyze the blood flow dynamics in renal artery stenosis with high-temporal-resolution cine phase-contrast magnetic resonance (MR) flow measurements.
  
  
  METHODS
  Cine phase-contrast MR flow measurements were invasively validated with real-time intraoperative transit-time ultrasound (US). In 23 patients, 48 renal artery stenoses were confirmed at digital subtraction angiography. Cardiac-gated cine phase-contrast MR flow measurements were obtained in 32-msec intervals, and flow curves were calculated for the whole cardiac cycle. Hemodynamic parameters evaluated included the decrease in mean flow and the delay and reduction in the systolic velocity maximum due to decrease in or absence of the early systolic peak.
  
  
  RESULTS
  Overall differentiation between renal artery stenosis (n = 31) and nonstenosed vessels (n = 17) with cine phase-contrast MR revealed a sensitivity of 90% and specificity of 94% compared with findings at digital subtraction angiography. High-grade stenoses (>50%, n = 19) were detected with cine phase-contrast MR with sensitivity of 100% and specificity of 93%.
  
  
  CONCLUSIONS
  Quantitative and qualitative analysis of cardiac-gated cine phase-contrast MR flow velocity curves provided a highly accurate method to detect hemodynamic abnormalities in patients with suspected renal artery stenosis.
authors.affiliation: Department of Radiology, German Cancer Research Center, Heidelberg.
authors.forename: S O
authors.initials: SO
authors.lastname: Schoenberg
authors.forename: M V
authors.initials: MV
authors.lastname: Knopp
authors.forename: M
authors.initials: M
authors.lastname: Bock
authors.forename: F
authors.initials: F
authors.lastname: Kallinowski
authors.forename: A
authors.initials: A
authors.lastname: Just
authors.forename: M
authors.initials: M
authors.lastname: Essig
authors.forename: H
authors.initials: H
authors.lastname: Hawighorst
authors.forename: L
authors.initials: L
authors.lastname: Schad
authors.forename: G
authors.initials: G
authors.lastname: van Kaick
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D000818:Animals; D001783:Blood Flow Velocity; D004285:Dogs; D005260:Female; D006439:Hemodynamics; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D012078:Renal Artery Obstruction / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D012680:Sensitivity and Specificity