Detection Of Focal Liver Lesions In Cirrhotic Liver Using Contrast-Enhanced Ultrasound

Table 1 Characteristics of common ultrasound contrast agents used in liver imaging

Agent	Manufacturer	Resonance range (MHz)	Chemical composition	MI level
Levovist®	Schering	2-3	Lipid	High > 0.6
			Air (galactose-based)
Definity®	BMS	1.5-4	Liposome	Low < 0.4
			Perfluorocarbon
SonoVue®	Bracco	1.8-3.2	Phospholipid	Low < 0.4
			Sulfur hexafluoride
Sonazoid®	GE healthcare	2-8	Lipid	Low < 0.4
			Perfluorocarbon

Table 2 Different phases of liver in contrast-enhanced ultrasound

Phase	Start1	End1
Arterial phase (s)	10-20	20-35
Portal venous phase (s)	30-45	120-180
Late phase (s)	120-180	240-360
Post-vascular or Kupffer phase	Approximately 10 min	At least 60 min

¹The individual global hemodynamic situation will influence the time of onset of different phases.

Table 3 Summary of contrast-enhanced ultrasound findings of common focal liver lesions[72]

	Arterial	Portal	Late vascular phase	Parenchymal phase
Malignant focal liver lesions
Hepatocellular carcinoma	Hyperechoic	Isoechoic	Hypo- or isoechoic (30%)	Hypoechoic
Metastases	Hypo- or hyperechoic (hypervascular)	Hypoechoic with or without rim enhancement	Hypoechoic	Hypoechoic
Cholangiocarcinoma	Hypo- or hyperechoic (15%)	Iso- or hypoechoic	Hypoechoic	Hypoechoic
Benign focal liver lesions
Regenerating nodules	Iso- or hypoechoic	Isoechoic	Isoechoic	Isoechoic
Dysplastic nodules	Hyper, iso- or hypoechoic	Isoechoic	Hypo- or isoechoic	Hypo- or isoechoic
Hemangiomas	Hyperechoic (peripheral nodular enhancement)	Centripetal filling	Isoechoic if filling is complete (intralesional hypoechoic areas in 50%)	Isoechoic (intralesional hypo-echoic areas in 50%)
	Homogenous hyperechoic in 20% of small hemangiomas	Hyper- or isoechoic	Hyper- or isoechoic	Isoechoic
Focal nodular hyperplasia	Hyperechoic	Hyper- or isoechoic; non-enhancing central scar in 45%	Hyper- or isoechoic; non-enhancing central scar in 45%	Hyper- or isoechoic
Hepatocellular adenoma	Hyperechoic	Isoechoic	Isoechoic	Isoechoic
Fatty changes or focal fatty sparing	Isoechoic	Isoechoic	Isoechoic	Isoechoic
Noncomplicated cysts	Absence of enhancement	Absence of enhancement	Absence of enhancement	Absence of enhancement