[Focal liver lesion, incidental finding]

Abstract

The differential diagnosis of incidentally found Focal Liver Lesions (FLL) is complex. Screening procedures so far are only defined for patients with liver cirrhosis. Characterization of a FLL begins as soon as it is detected. Taking patients history and thorough clinical examination are essential. An imaging procedure that is used to detect liver masses should also allow the examiner to determine whether the lesion is benign or malignant. Conventional B-mode US and colour Doppler imaging are effective at detecting and characterizing typical liver cysts and calcifications. Laboratory data, computed tomography, magnetic resonance imaging and imaging guided liver biopsy are complementary methods.Contrast Enhanced Ultrasound (CEUS) is a well established diagnostic imaging technique for a variety of indications and applications. One of the most important applications is in the liver where it is frequently a first-line technique for the detection and diagnosis (characterization) of focal liver lesions (FLL). In this setting the accurate differentiation of benign from malignant lesions is critical to ensure the patient undergoes the appropriate therapeutic option. This has been documented in recently published guidelines, in particular in terms of the enhancement patterns of the most common FLL hemangioma, focal nodular hyperplasia hepatocellular adenoma and their differentiation from malignant lesions. In this article the role of CEUS in the characterization of incidentally found FLL is described.