What is the sonographic appearance of a simple hepatic cyst?

A simple hepatic cyst typically presents as an anechoic structure on ultrasound. This means that it appears dark on the ultrasound image because it contains fluid, which does not reflect sound waves. The boundaries of a simple hepatic cyst are characterized by smooth, thin walls. This consistency and appearance are crucial for differentiating a simple cyst from more complex lesions or masses in the liver, which may have irregular borders or internal echoes.

In contrast, hyperechoic structures would appear brighter on ultrasound and would indicate something like a solid lesion or a different type of pathology. Thick walls usually signify inflammation or more complex processes, which do not align with the characteristics of a simple cyst. Similarly, echogenic structures or those with internal echoes indicate the presence of solid components or debris, again diverging from the classification of a simple cyst. Therefore, the right description of a simple hepatic cyst aligns perfectly with being anechoic and having smooth, thin walls.