Ultrasonographic hepatic pseudolesions: normal parenchyma mimicking mass lesions in fatty liver.

Fatty hepatic infiltration is usually diffuse but may be patchy or localized. Occasionally, focal areas of normal parenchyma in an otherwise diffuse fatty liver may mimic mass lesions. Typically, these pseudolesions appear as echopoor areas against a background of bright echoes due to fatty infiltration. We report five cases of sonographic pseudolesions with computed tomographic (CT) correlation. Sonographic features that may differentiate these pseudolesions from true abnormalities include their characteristic location in the quadrate lobe, nondisplacement of blood vessels and sometimes their straight-edged appearance of geometric pattern. When these features are present, further investigation is unnecessary. However, patchy foci of normal parenchyma may pose a difficult diagnostic problem which may necessitate computed tomography and biopsy for definitive diagnosis.