title: Morphologic and functional magnetic resonance imaging of renal artery stenosis: a multireader tricenter study.
abstract: The effect of combined morphologic and functional magnetic resonance (MR) imaging on the interobserver and intermodality variability for the grading of renal artery stenosis is assessed. In a randomized, blinded tricenter analysis, seven readers evaluated 43 renal arteries on x-ray digital subtraction angiography (DSA), 3D-Gadolinium MR angiography (3D-Gd-MRA), cine phase-contrast flow measurement (PC-flow), and a combined analysis of the last two. Interobserver variability was assessed for the grading of renal artery stenosis as well as regional vessel visibility. Intermodality variability for stenosis grading was analyzed in cases in which the readers agreed on the degree of stenosis in DSA. DSA had a substantial interobserver variability for the grading of stenosis (mean kappa kappa 0.64). 3D-Gd-MRA revealed a slightly improved interobserver variability but incorrectly graded 6 of 34 stenoses on a two-point scale (<50%, > or =50%). The combined approach of 3D-Gd-MRA and PC-flow revealed the best (P = 0.0003) interobserver variability (median kappa = 0.75) and almost perfect intermodality agreement with DSA (97% of cases). These findings were confirmed in a prospective analysis of 97 renal arteries. The vessel visibility of the renal artery ostium was significantly better in 3D-Gd-MRA than in DSA, whereas the visibility of the hilar and intrarenal vessels was significantly worse (P = 0.0001). A combined morphologic and functional MR examination significantly reduces interobserver variability and offers reliable and reproducible grading of renal artery stenosis based on stenosis morphology and hemodynamic changes. It can be considered a safe and noninvasive alternative for diagnostic DSA in cases that do not require assessment of intrarenal vessels.
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Stefan O
authors.initials: SO
authors.lastname: Schoenberg
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Michael V
authors.initials: MV
authors.lastname: Knopp
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Frank
authors.initials: F
authors.lastname: Londy
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Sumati
authors.initials: S
authors.lastname: Krishnan
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Ivan
authors.initials: I
authors.lastname: Zuna
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Nicole
authors.initials: N
authors.lastname: Lang
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Marco
authors.initials: M
authors.lastname: Essig
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Hans
authors.initials: H
authors.lastname: Hawighorst
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Maki
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: David
authors.initials: D
authors.lastname: Stafford-Johnson
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Kallinowski
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Chenevert
authors.affiliation: *Department of Radiology, University of Michigan, Ann Arbor, Michigan; Department of Radiology, German Cancer Research Center (dkfz), and Department of Surgery, University Hospitals, Heidelberg, Germany; and Department of Radiology, Veteran Affairs Medical Center, Ann Arbor, Michigan.
authors.forename: Martin R
authors.initials: MR
authors.lastname: Prince
mesh_terms: D000368:Aged; D015901:Angiography, Digital Subtraction; D005260:Female; D005682:Gadolinium; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008858:Microscopy, Phase-Contrast; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D012039:Regional Blood Flow; D012078:Renal Artery Obstruction / Q000175:diagnosis* / Q000503:physiopathology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012212:Rheology / Q000379:methods
chemical_list: D005682:Gadolinium