title: Quantification of Single-Kidney Function and Volume in Living Kidney Donors Using Dynamic Contrast-Enhanced MRI.
abstract: OBJECTIVE
  The objective of our study was to investigate whether dynamic contrast-enhanced MRI (DCE-MRI) can detect differences and potential adaption in single-kidney parenchymal volume, blood flow, glomerular filtration rate (GFR), and filtration fraction in the remaining kidney of healthy donors compared with nondonors. Further, we evaluated the agreement in donor GFRs measured using DCE-MRI versus serum clearance of iohexol.
  
  
  METHODS
  Twenty living kidney donors and 20 healthy control subjects underwent DCE-MRI and iohexol GFR. Renal parenchymal volume was assessed from maximum-signal-intensity maps. Single-kidney MRI measurements of blood flow and GFR were derived from parenchymal signal intensity-time curves fitted to a two-compartment filtration model. The Student t test, Pearson correlation coefficient, mean differences, and limits of agreement were applied to analyze MRI measurements between groups and agreement with iohexol GFR.
  
  
  RESULTS
  MRI findings showed significantly higher blood flow (difference in mean values of donors vs control subjects, 54%; p = 0.001), GFR (78%, p < 0.0001), and renal parenchymal volume (65%, p < 0.0001) in the single kidney of donors compared with the single kidney of healthy control subjects. In the donors, a proportional increase in blood flow and GFR resulted in a comparable filtration fraction, as was observed in the control subjects. Significant correlations were found between MRI-derived GFR and parenchymal volume (p < 0.0016) as well as with iohexol GFR (p < 0.0001). The mean difference between MRI-derived GFR and iohexol GFR was 14.0 mL/min, and the limits of agreement between MRI-derived GFR and iohexol GFR were -24.1 and 52.1 mL/min.
  
  
  CONCLUSIONS
  DCE-MRI-derived values for single-kidney function and volume in kidney donors were significantly higher than those in control subjects and suggest a future potential benefit of DCE-MRI for diagnostic and prognostic structural and functional assessments in living kidney donors.
authors.affiliation: 1 Department of Radiology, Haukeland University Hospital, PO Box 1400, 5021 Bergen, Norway.|2 Department of Clinical Medicine, University of Bergen, Bergen, Norway.
authors.forename: Eli
authors.initials: E
authors.lastname: Eikefjord
authors.affiliation: 1 Department of Radiology, Haukeland University Hospital, PO Box 1400, 5021 Bergen, Norway.|3 Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway.
authors.forename: Erling
authors.initials: E
authors.lastname: Andersen
authors.affiliation: 4 MedViz, Research Cluster, University of Bergen, Bergen, Norway.|5 Christian Michelsen Research AS, Bergen, Norway.
authors.forename: Erlend
authors.initials: E
authors.lastname: Hodneland
authors.affiliation: 2 Department of Clinical Medicine, University of Bergen, Bergen, Norway.|6 Department of Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Einar
authors.initials: E
authors.lastname: Svarstad
authors.affiliation: 1 Department of Radiology, Haukeland University Hospital, PO Box 1400, 5021 Bergen, Norway.|7 Department of Biomedicine, University of Bergen, Bergen, Norway.
authors.forename: Arvid
authors.initials: A
authors.lastname: Lundervold
authors.affiliation: 1 Department of Radiology, Haukeland University Hospital, PO Box 1400, 5021 Bergen, Norway.|2 Department of Clinical Medicine, University of Bergen, Bergen, Norway.
authors.forename: Jarle
authors.initials: J
authors.lastname: Rørvik
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003287:Contrast Media; D003430:Cross-Sectional Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007472:Iohexol; D007668:Kidney / Q000098:blood supply / Q000502:physiology*; D016030:Kidney Transplantation; D019520:Living Donors; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D003287:Contrast Media; D007472:Iohexol
keywords: dynamic contrast-enhanced MRI; iohexol glomerular filtration rate (GFR); kidney parenchymal volume; living kidney donor; single-kidney function