What type of liver mass appears as a hyperechoic mass with posterior enhancement?

A cavernous hemangioma is a type of benign vascular tumor of the liver that typically appears as a hyperechoic mass on ultrasound. This is due to its high vascularity and the presence of many blood vessels, which reflect sound waves very efficiently, resulting in a bright appearance on the ultrasound image. The characteristic posterior enhancement observed with cavernous hemangiomas occurs because the mass is filled with blood vessels, which helps transmit sound waves and leads to increased echo amplitude. Additionally, the acoustic properties of the surrounding liver tissue allow for the enhancement effect to be noted posterior to the mass.

Understanding the specific ultrasound characteristics of various liver masses helps in differentiating between them, as other types, while they might also have a hyperechoic appearance, do not consistently show the same degree of posterior enhancement as cavernous hemangiomas do. For instance, hepatic adenomas are often hypervascular but may not consistently demonstrate significant posterior enhancement due to their composition. Liver cysts typically present as anechoic areas with good transmission rather than hyper-echoic, and focal nodular hyperplasia may vary in echogenicity but does not classically show the pronounced posterior enhancement characteristic of cavernous hemangiomas.