title: Magnetic resonance imaging of liver metastases: experimental comparison of anionic and conventional superparamagnetic iron oxide particles with a hepatobiliary contrast medium during dynamic and uptake phases.
abstract: OBJECTIVE
  To assess the contrast-enhancing effects of citrate-coated superparamagnetic iron oxide particles (VSOP-C184) in a rat liver tumor model using dynamic and delayed magnetic resonance imaging in comparison to carboxydextran-coated particles (ferucarbotran) and a hepatobiliary contrast medium (gadobenate dimeglumine).
  
  
  METHODS
  A total of 32 male rats with liver tumors (CC-531 colorectal carcinoma) were examined at 1.5 T with a T1-weighted dynamic series (3D gradient echo sequence) and T1-weighted and T2*-weighted images (2D gradient echo sequences) before and 15 and 90 minutes after injection. VSOP-C184 was investigated at doses of 0.015, 0.045, and 0.06 mmol Fe/kg, ferucarbotran at 0.015 mmol Fe/kg, and gadobenate dimeglumine at 0.025, 0.05, and 0.1 mmol Gd/kg. Liver-tumor contrast-to-noise ratio (CNR) was calculated and statistically compared.
  
  
  RESULTS
  T1-weighted dynamic images: VSOP-C184 has significantly higher CNR values at a dose of 0,015 mmol Fe/kg than ferucarbotran at the same dose (P = 0.001). VSOP-C184 produces a significantly higher CNR at a dose of 0.045 mmol Fe/kg than gadobenate dimeglumine at a dose of 0.05 mmol Gd/kg (P = 0.019). At a dose of 0.06 mmol Fe/kg, the CNR for VSOP-C184 is significantly lower than that of gadobenate dimeglumine (0.1 mmol Gd/kg) (P = 0.005).T2-weighted delayed images: CNR values of VSOP-C184 are similar to those of ferucarbotran and are significantly higher than those of gadobenate dimeglumine (P < 0.05).
  
  
  CONCLUSIONS
  On T1-weighted magnetic resonance imaging of liver tumors VSOP-C184 produces a high contrast comparable to that of a hepatobiliary contrast medium in addition to its contrast-enhancing effect in T2-weighted imaging.
authors.affiliation: Departments of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Nicola
authors.initials: N
authors.lastname: Kaufels
authors.forename: Ronny
authors.initials: R
authors.lastname: Korn
authors.forename: Susanne
authors.initials: S
authors.lastname: Wagner
authors.forename: Tania
authors.initials: T
authors.lastname: Schink
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Matthias
authors.initials: M
authors.lastname: Taupitz
authors.forename: Jörg
authors.initials: J
authors.lastname: Schnorr
mesh_terms: D000818:Animals; D000838:Anions; D003287:Contrast Media / Q000493:pharmacokinetics; D003911:Dextrans; D052203:Ferrosoferric Oxide; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D007501:Iron / Q000493:pharmacokinetics*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008657:Metabolic Clearance Rate; D009928:Organ Specificity; D010087:Oxides / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
chemical_list: D000838:Anions; D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; C097921:ferumoxtran-10; D007501:Iron; D019786:Gadolinium DTPA; D052203:Ferrosoferric Oxide