November 21, 2010

Contrast Agents for Liver MRI

Gadolinium Chelates
  • Most commonly used contrast agent
  • Standard dose 0.1 mmol Gd/kg
  • Bolus injection, dynamic study during arterial (20-30s) to detect hypervascular lesions, portovenous phase (60-90s) to detect hypovascular lesions, and equilibrium phase (between 2-10 min) to allow hemangiomas to fill-in and cholangiocarcinoma and inflammation to enhance
Liver-Specific Agents
  • Teslascan (Mn-DPDP)
  • MultiHance (gadobenate dimeglumine)
  • Primovist (gadoxetic acid)
  • SPIO (Endorem/Feridex)
  • Hepatocyte-specific MR contrast agent
  • Uptake into hepatocyte and partially excretes into the bile
  • Drip infusion
  • Increased T1 signal intensity
  • Differentiate tumors of hepatocellular origin from nonhepatocellular origin
  • 4% biliary excretion
  • Can be bolus injected, images also taken 1-2 hours later for tumor detection (uptake into liver parenchyma to increase conspicuity of metastases)

  • Strong biliary excretion
  • Can be bolus injected (doses 0.025 mmol/kg), images on delayed phase can be taken as early as 20 min
Superparamagnetic Iron Oxide Particles (SPIO)
  • Accumulates within phagocytes in the liver (typically, there is absence of phagocytes in malignancy)
  • On T2WI, normal tissues or lesions with phagocytes (ie, FNH, hepatocellular adenoma, well-differentiated HCC) appear dark
  • Drip infusion
  • Imaging done several hours after contrast administration
Above image: gadolinium metal, from

Reimer P, Parizel PM, Meaney JFM, Stichnoth FA. Clinical MR Imaging, 2010

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