Troubleshooting Arterial-Phase MR Images of Gadoxetate Disodium-Enhanced Liver

Abstract

Gadoxetate disodium is a widely used magnetic resonance (MR) contrast agent for liver MR imaging, and it provides both dynamic and hepatobiliary phase images. However, acquiring optimal arterial phase images at liver MR using gadoxetate disodium is more challenging than using conventional extracellular MR contrast agent because of the small volume administered, the gadolinium content of the agent, and the common occurrence of transient severe motion. In this article, we identify the challenges in obtaining high-quality arterial-phase images of gadoxetate disodium-enhanced liver MR imaging and present strategies for optimizing arterial-phase imaging based on the thorough review of recent research in this field.

Keywords: Arterial phase; Gadoxetate disodium; Liver; Magnetic resonance imaging; Transient severe motion.

Fig. 1. Simulated contrast enhancement curve of abdominal aorta and liver.

Small amount of administered volume and gadolinium content of gadoxetate disodium (red line) can potentially shorten enhancement duration of contrast bolus and decrease magnitude of peak enhancement of contrast bolus compared with favorable contrast bolus curve (green line). This shape of gadoxetate disodium curve (red line) can pose challenges in capturing optimal arterial phase imaging.

Fig. 2. 68-year-old man with respiratory motion artifacts.

This arterial phase image of gadoxetate-enhanced liver MR (B) is severely contaminated by respiratory motion artifacts related to TSM, whereas noncontrast (A), portal venous (C), and hepatobiliary (D) phase images look fine. Owing to presence of TSM, arterial hypervascularity of lesion in right lobe of liver (arrows) cannot be exactly evaluated on this MR image, although lesion (arrows) is clearly defined on non-contrast (A), portal venous (C), and hepatobiliary (D) phase images. Lesion was confirmed as HCC after surgery. HCC = hepatocellular carcinoma, TSM = transient severe motion

Fig. 3. 71-year-old man who underwent liver MRI both at 1.5T and 3T in one-week interval.

On arterial phase images at 3T (A, B), four more lesions (arrows) as well as large hypervascular tumor (arrowheads) are additionally detected, whereas on 1.5T MR images (C, D), only main lesion (arrowheads) is found. Lesions look more conspicuous on 3T MR images (A, B) than they do 1.5T MR images (C, D). Non-enhanced follow-up CT images (E, F) after transarterial chemoembolization demonstrate lipidol uptakes on four small lesions (arrows) and main lesion (arrowheads).