title: Gadoxetate disodium-enhanced hepatic MRI: dose-dependent contrast dynamics of hepatic parenchyma and portal vein.
abstract: OBJECTIVE
  The purpose of this study was to investigate the relative enhancement characteristics of the hepatic parenchyma and portal vein during gadoxetate disodium-enhanced abdominal MRI and to assess whether contrast between the portal vein and the hepatic parenchyma can be improved with higher doses of gadoxetate disodium.
  
  
  METHODS
  A total of 102 patients (61 women, 41 men) underwent gadoxetate disodium-enhanced abdominal MRI. They received a weight-independent dose of 10 mL of gadoxetate disodium, corresponding to a dose spectrum of 0.02-0.06 mmol/kg body weight. The patients were assigned to one of three dose groups: recommended dose (0.02-0.03 mmol/kg), intermediate dose (0.03-0.045 mmol/kg), or high dose (0.045-0.06 mmol/kg). The signal-to-noise ratios for the portal vein, liver, and the portal vein-to-liver contrast-to-noise ratio were calculated for three consecutive arterial phases, one portal venous phase, and four delayed imaging phases.
  
  
  RESULTS
  The delayed phase images of the liver showed statistically significant dose dependency and greater enhancement in the intermediate- and high-dose groups (p < 0.01). Analogously, the portal vein also exhibited greater enhancement in the two higher-dose groups, but the difference was not statistically significant (p > 0.05). Regarding portal vein-to-liver contrast, all three groups had a dose-independent fast parallel increase from baseline toward maximum contrast followed by a steady decline in contrast with no statistically significant differences between dose groups (p > 0.05).
  
  
  CONCLUSIONS
  Portal vein-to-liver contrast during gadoxetate disodium-enhanced hepatic MRI cannot be improved within a dose spectrum of 0.025-0.06 mmol/kg body weight.
authors.affiliation: Department of Radiology, University of Ulm, Ulm, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Feuerlein
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Boll
authors.forename: Rajan T
authors.initials: RT
authors.lastname: Gupta
authors.forename: Kristina I
authors.initials: KI
authors.lastname: Ringe
authors.forename: Daniele
authors.initials: D
authors.lastname: Marin
authors.forename: Elmar M
authors.initials: EM
authors.lastname: Merkle
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D016014:Linear Models; D008107:Liver Diseases / Q000175:diagnosis*; D008111:Liver Function Tests; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA