Diagnosis and differential diagnosis of liver abscesses using contrast-enhanced (SonoVue) ultrasonography

To describe the ultrasonographic findings in liver abscesses after the administration of a second generation agent. To perform the differential diagnosis of liver abscesses with other focal liver lesions. We evaluated 28 liver abscesses in 5 patients before and after the administration of SonoVue. We also evaluated liver lesions in six patients in whom the differential diagnosis with liver abscess was considered in the baseline ultrasonographic examination. A typical enhancement pattern consisting of peripheral ring enhancement in the arterial phase and absence of central enhancement was observed in 21 (75%) abscesses. In another 6 (21.4%) abscesses, arterial enhancement was seen in large areas of the lesion, while other areas showed no uptake. One case (3.6%) had a multiseptated pattern of enhancement. Segmental hepatic enhancement was observed in 6 abscesses. In the liver lesions in which the differential diagnosis with abscess was carried out, 5 of the 6 showed no enhancement in any phase. The other lesion, a cystic metastasis, had irregular peripheral enhancement in the arterial phase. None of these lesions had segmental hepatic enhancement in the arterial phase. Contrast administration improves the performance of ultrasonography in the diagnosis of liver abscesses. There are three patterns of enhancement and these correlate well with the findings at CT and MRI. Contrast-enhanced ultrasonography is very useful for defining the internal architecture of the abscess, which is important for choosing the type of treatment. Contrast-enhanced ultrasonography also enables the differential diagnosis with other focal liver lesions.