[Contrast-enhanced ultrasound in hepatic focal nodular hyperplasia]

The ultrasound contrast agent is composed by microbubbles of sulfur hexafluoride. It is now recognized to the characterization of liver lesions. Focal nodular hyperplasia (FNH) is a benign lesion of the liver. It is found in the majority of cases among women with a sex ratio 1M/8F, no typical clinical presentation or malignancy is described. When the liver lesion was found in B-mode ultrasound, injection of contrast can be realized immediately by the radiologist. The study of the lesion during the arterial, portal and late phases with the contrast-enhanced ultrasound allows the diagnosis of FNH with a specificity of 97%. In arterial phase, the prescence of a central artery and scarring, centrifugal progression of enhancement, a transient unenhanced zone and in portal and late phases, isoechogenicity compared to adjacent parenchyma are the main features of FNH described in the literature.