Contrast Agents for Hepatic Magnetic Resonance Imaging

Abstract

The current availability of liver-specific contrast media (LSCM) allows the possibility to obtain an accurate diagnosis when studying focal liver lesions (FLL). It is necessary to have an in-depth knowledge of the biologic and histologic characteristics of FLL and the enhancement mechanism of LSCM to gain significant accuracy in the differential diagnosis of FLL. It is possible to subdivide FLL into three main groups according to the kinetics of contrast enhancement: hypervascular FLL, hypovascular FLL, and FLL with delayed enhancement. Dynamic contrast-enhanced magnetic resonance imaging is an important tool in the identification and characterization of FLL. LSCM with a first phase of extracellular distribution give both dynamic (morphologic) and late phase (functional) information useful for lesion characterization. With LSCM it is possible to differentiate with high accuracy benign from malignant lesions and hepatocellular from nonhepatocellular lesions. To understand contrast behavior after injection of LSCM, it is necessary to correlate contrast enhancement with the biologic and histologic findings of FLL.

Magnetic resonance imaging with liver-specific contrast agent in primary amyloidosis and intrahepatic cholestasis

“…In dynamic CT scan, hypoattenuating focal areas have been observed on delayed-phase images (5 min) and explained by prominent infiltration of the parenchyma in the focal areas, and hence delayed passage of the contrast medium (12). Similar findings may have been found by using Gd-based liver-specific agents.…”

Gadobenate Dimeglumine-Enhanced Liver MRI as the Sole Preoperative Imaging Technique: A Prospective Study of Living Liver Donors

“…However, MRA and cholangiography have limited temporal and spatial resolution compared with direct DSA and intraoperative cholangiography. From this point of view, we speculate that the twofold T1 relaxation afforded by gadobenate dimeglumine provides a higher SNR of the vascular structure on MRA than other gadolinium chelates and its biliary excreting feature contributes to improving the evaluation of the biliary anatomy by allowing delayed 3D T1-weighted MR cholangiography [9,10].…”

“…Based on previous studies, the use of gadobenate dimeglumine for liver MR examinations as a preoperative workup for a living donor transplantation seems to be attractive because of its twofold T1 relaxation effects and biliary excretion property [1,9,10]. The motivation for our study was from the possibility for gadobenate dimeglumine to increase the signal-to-noise ratio (SNR) of MRA due to its twofold T1 relaxation effect and its biliary excretion property to be used for 3D cholangiography.…”

Biocompatible superparamagnetic iron oxide nanoparticles used for contrast agents: a structural and magnetic study

“…MION particles are cleared from the blood by phagocytosis accomplished by reticuloendothelial system (RES), usually lacking in most malignant liver lesions, so that uptake is observed in the normal liver, spleen, bone marrow, and lymph nodes. Inflammation, scarring, regeneration, and shunting in cirrhotic liver reduces hepatic uptake of MION, shifts distribution to the spleen, and produces signal heterogeneity [1,2]. From the magnetic point of view, MION contrast media consist of subdomain iron oxide particles, mainly magnetite (Fe 3 O 4 ) or maghemite (g-Fe 2 O 3 ) phases that display high saturation magnetic moments (M S E90 emu/g).…”