Diagnostic Challenges and Pitfalls in MR Imaging with Hepatocyte-specific Contrast Agents

Abstract

The use of gadolinium-based hepatocyte-specific contrast agents (HSCAs) has increased markedly since their introduction, and hepatocellular phase imaging performed with an HSCA is now a key part of the standard magnetic resonance (MR) imaging work-up for focal liver lesions. An understanding of the mechanisms of action of HSCAs helps ensure their effective use. The optimal delay for hepatocellular phase image acquisition differs between the two currently available HSCAs, gadoxetic acid and gadobenate dimeglumine, and MR imaging protocols must be adjusted accordingly. In addition, familiarity with typical and atypical appearances of benign and malignant focal liver lesions at HSCA-enhanced hepatocellular phase MR imaging, along with knowledge of the processes that are most likely to produce atypical appearances, is required to achieve optimal diagnostic accuracy.

Comparison of high spatial resolution respiratory triggered inversion recovery‐prepared spoiled gradient echo sequence with standard breathhold T1 sequence MRI of the liver using gadoxetic acid

“…This is due to increased signal intensity of liver parenchyma in the hepatobiliary phase (11,12) contrasting with lack of uptake in nonhepatocyte lesions. In addition, the uptake of contrast in hepatocyte containing lesions can help with characterization (13). Due to the prolonged enhancement of the liver parenchyma in the hepatocyte phase (14), sequences that are not as time critical in acquisition have been developed in an attempt to further enhance the advantages of gadoxetic acid.…”

Imaging of Cholangiocarcinoma

“…A typical MRI protocol for the assessment of CC encompasses magnetic resonance cholangiopancreatography (MRCP), conventional T1- and T2-weighted sequences, as well as diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI [48]. Furthermore, MRI with hepatocyte-specific contrast agents is often performed for the assessment of CC [49]. …”

New Paradigm for Management of Hepatocellular Carcinoma by Imaging

“…These agents are taken up by normally functioning hepatocytes and are excreted into the biliary system. Because hepatocyte-specific contrast agents have a biphasic nature, the perfusion function in the vascular phase and the hepatocyte function in the hepatobiliary phase can be evaluated [100][101][102]. Dynamic MRI using extracellular contrast agents provides sufficient information to make a confident diagnosis of typical enhancing HCC.…”

“…An antibody against CD34 is used for sinusoidal capillarization, α-smooth muscle actin for unpaired artery, CD68 for Kupffer cells, and CEA for bile canaliculi [126,133,148]. For imaging evaluation, various contrast agents, such as extracellular contrast agents, RES agents, and hepatocyte-specific agents, can be used to obtain functional images that reflect molecular pathological features of hepatocarcinogenesis [100,149]. As molecular and imaging techniques advance and develop, further studies are needed to correlate pathological and imaging features in hepatocarcinogenesis and document their usefulness in clinical practice.…”