Contrast Ultrasound of the Liver and Gallbladder

RC110A

Contrast Ultrasound of the Liver and Gallbladder

Refresher/Informatics

Presented on November 30, 2014
Presented as part of RC110: Liver and Gallbladder Ultrasound including Elastography and Contrast

Hans-Peter Weskott MD, Presenter: Luminary, General Electric Company Speaker, Bracco Group

1) Understanding the indications of contrast enhanced ultrasound (CEUS) in focal liver and gallbladder diseases. 2) Learning about the importance of the three contrast phases and how CEUS performes in detecting and characterizing focal liver lesions and to characterize inflammatory and tumorous changes of the gallbladder wall. 3) Learning about the potential value as well as the limitations of CEUS in liver an gallbladder diseases. 4) Learning how CEUS performs when compared to B-mode and Color Doppler ultrasound, CT and MRI imaging.

Liver: In patients with favorable scanning conditions CEUS is at least as sensitive as contrast enhanced CT (CECT) in detecting malignant liver lesions. Due to its high temporal resolution even a short hyperenhancement of a few seconds can reliably be detected this improving the characterization of focal liver lesions (FLL). A majority of FLL can therefore be characterized as iso- or hyperenhancing. During the arterial phase the tumor vessel supply and the tumor`s vessel architecture and direction of contrast filling is important in characterizing FLL. Due to a high spatial resolution novel contrast imaging techniques allow detection of washed out lesions down to 3mm in size. CEUS characterizes FLL with a much higher confidence than conventional US techniques and is comparable to CECT and CEMRI. CEUS also improves intraoperative tumor detection and characterization. Using time intensity analysis a change in contrast enhancement over time helps in estimating tumor response to chemotherapy. CEUS is also used to monitor local ablation therapy and is useful to early detect local tumor recurrence. Gallbladder: CEUS can be used to better visualize ulceration, perforation and tumors of its wall. It thus helps to improve the patient`s clinical management including timing for surgery. CEUS does not affect renal or thyroid function and is therefore helpful in older patients and should be the first line contrast imaging technique in patients with impaired renal function.