title: Renal artery stenosis evaluation in chronic kidney disease patients: nonenhanced time-spatial labeling inversion-pulse three-dimensional MR angiography with regulated breathing versus DSA.
abstract: OBJECTIVE
  To evaluate the diagnostic performance of nonenhanced magnetic resonance (MR) angiographic flow-in technique with three-dimensional balanced steady-state free precession (SSFP) (flow-in balanced SSFP), compared with digital subtraction angiography (DSA) as reference standard, for assessment of renal artery stenosis (RAS) in chronic kidney disease (CKD) patients.
  
  
  METHODS
  Institutional review board approval and written informed consent were obtained for this prospective HIPAA-compliant study. Twenty-three patients, 13 men (mean age, 67.6 years ± 8.1 [standard deviation]; age range, 58-86 years) and 10 women (mean age 73.1 years ± 12.4; age range, 49-89 years), were evaluated with flow-in balanced SSFP and DSA. Coronal and axial flow-in balanced SSFP images were obtained with 1.5-T system, with regulated breathing (recorded voice instruction). The quality of flow-in balanced SSFP images was visually evaluated; the degree of stenosis was compared between flow-in balanced SSFP source images and DSA images by using the Wilcoxon signed-rank test. Correlation between images from both modalities was calculated as the Spearman rank-order correlation coefficient; bias was examined with Bland-Altman plots.
  
  
  RESULTS
  Diagnostic images were obtained in all patients. Flow-in balanced SSFP image quality was good in 87% (20 of 23) and moderate in 13% (three of 23) of patients. Forty-five renal arteries were included in the statistical analysis. Of 36 stenoses detected with flow-in balanced SSFP, 28 were relevant (degree of stenosis, ≥ 50%). The stenosis measurements of flow-in balanced SSFP were highly correlated (ρ = 0.91, P < .001) with those of DSA. The Bland-Altman plot showed a slight overestimation of the degree of stenosis (mean bias, 2.33% ± 11.95). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of flow-in balanced SSFP relative to DSA for the diagnosis of a stenosis of 50% or greater were 93% (26 of 28), 88% (15 of 17), 93% (26 of 28), 88% (15 of 17), and 91% (41 of 45), respectively.
  
  
  CONCLUSIONS
  Flow-in balanced SSFP with regulated breathing is an appropriate nonenhanced MR angiographic technique for RAS assessment in CKD patients.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101422/-/DC1.
authors.affiliation: Imagerie du Bois de Verrières, Antony, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Parienty
authors.forename: Guy
authors.initials: G
authors.lastname: Rostoker
authors.forename: Francis
authors.initials: F
authors.lastname: Jouniaux
authors.forename: Michel
authors.initials: M
authors.lastname: Piotin
authors.forename: Faiza
authors.initials: F
authors.lastname: Admiraal-Behloul
authors.forename: Mitsue
authors.initials: M
authors.lastname: Miyazaki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012078:Renal Artery Obstruction / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D051436:Renal Insufficiency, Chronic / Q000150:complications*; D018709:Statistics, Nonparametric