Which imaging finding is associated with focal nodular hyperplasia of the liver?

Focal nodular hyperplasia (FNH) of the liver is characterized by a hypervascular mass, which is typically well-circumscribed, and in many cases, it demonstrates areas of arterial supply with accompanying vascular connections that may resemble arteriovenous connections. This is a crucial point because the lesion’s vascularity differentiates it from other hepatic lesions, such as hepatic adenomas or hemangiomas.

The hypervascularity in FNH is due to the presence of abnormal blood vessels that are a result of the underlying hepatic tissue architecture affected by a central scar, which can contribute to the lesion's distinctive imaging characteristics. Radiologic studies, typically using contrast-enhanced imaging techniques like CT or MRI, will reveal this hypervascular pattern.

The other options present different scenarios: a poorly encapsulated mass could suggest a malignant process, while calcified lesions are more associated with conditions such as metastatic calcifications or hemangiomas. Cystic formations are indicative of different pathologies, such as hepatic cysts or polycystic liver disease, neither of which would present with the typical findings seen in FNH. Thus, the defining imaging characteristic of a hypervascular mass with potential arteriovenous connections is what makes option B the most accurate