Contrast ultrasound agents  improve the display of vascularity of liver lesions. resulting in a more specific lesion characterisation.

Focal liver lesions have a specific vascular supply which is characteristic for the specific lesion type and usually different from normal liver tissue with an early and weak arterial enhancement and a stronger portal-venous and late enhancement.

The abnormal (chaotic) vascularity of the hepatocellular carcinoma (HCC) can easily be demonstrated at the very early contrast inflow phase. Liver metastases can be characterised reliably in the late phase.

The advantage of CEUS is that all phases (from the very early arterial phase to the late phase 6-8 min after injection) can be continuously seen, so that no relevant phases and patterns are missed.