title: Solid focal liver lesions indeterminate by contrast-enhanced CT or MR imaging: the added diagnostic value of contrast-enhanced ultrasound.
abstract: The main clinically recognized application of contrast-enhanced US (CEUS) with microbubble contrast agents is the characterization of incidental focal liver lesions. CEUS with low transmit power insonation allows the real-time assessment of contrast enhancement in a focal liver lesion after microbubble contrast agent injection, during the arterial (10-25 s), portal venous (from 35 s up to 2 min) and late phase (4-6 min after microbubble injection). During the portal venous and late phase benign lesions appear hyper or iso-enhancing in comparison to the adjacent liver parenchyma, while malignant lesions prevalently present contrast washout with hypo-enhancing appearance. CEUS may provide an added diagnostic value in those incidental focal liver lesions in which contrast-enhanced CT or MR imaging are not conclusive. In particular, CEUS may provide an added diagnostic value in those focal liver lesions appearing indeterminate on single-phase CT scan, or on CT scans performed by an incorrect delay time or also after injection of a low dose of iodinated contrast agent, or also in those focal liver lesions revealing equivocal enhancement patterns on contrast-enhanced CT or MR imaging. CEUS may have an added diagnostic value also in hepatocellular nodules in a cirrhotic liver and can be considered a complementary imaging technique to CT.
authors: Department of Radiology, Cattinara Hospital, University of Trieste, Italy. quaia@units.it
authors: Emilio
authors: E
authors: Quaia
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D006391:Hemangioma / Q000000981:diagnostic imaging; D006801:Humans; D007089:Image Enhancement; D033162:Incidental Findings; D008103:Liver Cirrhosis / Q000150:complications; D008107:Liver Diseases / Q000000981:diagnostic imaging; D008113:Liver Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000556:secondary; D008279:Magnetic Resonance Imaging; D045423:Microbubbles; D011856:Radiographic Image Enhancement; D011877:Radionuclide Imaging; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography