title: Half-dose gadobenate dimeglumine versus standard-dose gadodiamide in dynamic magnetic resonance imaging of non-cirrhotic livers: a retrospective intra-individual crossover comparison.
abstract: OBJECTIVE
  The purpose of this study was to compare enhancement characteristics of half-dose gadobenate dimeglumine (0.05 mmol kg(-1)) with standard-dose gadodiamide (0.10 mmol kg(-1)), in the assessment of hepatic vessels and lesions, using retrospective intra-individual crossover comparison methodology.
  
  
  METHODS
  Ethics committee approval was obtained. From 2004 to 2012, 21 patients underwent MRI examination with both standard-dose gadodiamide and half-dose gadobenate dimeglumine, using the same liver MRI protocol at 1.5 T. Eighteen patients whose scans showed no artifacts were selected. Quality of liver lesion [12 hemangiomas, 7 focal nodular hyperplasias (FNHs)] and liver vessel enhancement, and the global diagnostic quality of studies were ranked on a scale of 1-4 by two independent radiologists. Contrast-to-noise ratio (CNR) and % enhancement of liver vessels and lesions were calculated based on region of interest, signal intensity, and noise standard deviation measurements performed at 0, 20 s, 1, 3, and 5 min post-contrast injection. Qualitative and quantitative results were compared using the paired Wilcoxon signed rank and Student's t-tests, respectively.
  
  
  RESULTS
  No qualitative differences were noted in enhancement of liver vessels, hemangiomas, and FNHs. There was no statistically significant difference between the global diagnostic qualities of scans performed with the two contrast agents. Quantitatively, liver vessels and hemangiomas did not demonstrate statistically significant differences in contrast enhancement. At 20 s, FNHs achieved higher CNR (P = 0.02) with gadodiamide.
  
  
  CONCLUSIONS
  Half-dose gadobenate dimeglumine results in similar contrast enhancement compared to standard-dose gadodiamide in assessment of liver vessels, hemangiomas, and FNHs, and is a reasonable alternative to standard doses of extracellular agents in dynamic liver MRI.
authors.affiliation: Department of Diagnostic Radiology, University of British Columbia, 3350-950 W 10th Avenue, Vancouver, BC, V5Z 4E3, Canada, behrangh@alumni.ubc.ca.
authors.forename: Behrang
authors.initials: B
authors.lastname: Homayoon
authors.forename: Himanshu
authors.initials: H
authors.lastname: Diwakar
authors.forename: Evgeny
authors.initials: E
authors.lastname: Strovski
authors.forename: Darshan
authors.initials: D
authors.lastname: Bakshi
authors.forename: Alison C
authors.initials: AC
authors.lastname: Harris
authors.forename: Ruedi F
authors.initials: RF
authors.lastname: Thoeni
authors.forename: Silvia D
authors.initials: SD
authors.lastname: Chang
mesh_terms: D003287:Contrast Media; D018592:Cross-Over Studies; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008099:Liver / Q000473:pathology; D008107:Liver Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine; C064925:gadodiamide; D019786:Gadolinium DTPA