Symptomatic and complicated nonhereditary developmental liver cysts: cross-sectional imaging findings

Commonly encountered in the general population, in the vast majority of cases nonhereditary developmental liver cysts are asymptomatic, not associated with altered hepatic function and confidently diagnosed on imaging studies, and do not require further workup, follow-up, or treatment. However, particularly in women, simple hepatic cysts may reach large sizes and cause symptoms and signs resulting from mass effect, vascular compression, and biliary obstruction. Furthermore, although rarely compared to the incidence observed in patients with adult polycystic kidney and liver disease, sporadic hepatic cysts sometimes undergo life-threatening complications such as intracystic hemorrhage, infection, or rupture, which require prompt imaging triage and appropriate interventional, laparoscopic, or open surgical treatment. This pictorial essay reviews with examples the cross-sectional imaging findings of symptomatic and complicated nonhereditary liver cysts, aiming to provide radiologists with an increased familiarity with these uncommon, challenging occurrences. Emphasis is placed on the role of MRI as a useful problem-solving modality to elucidate the complex imaging appearances resulting from intracystic bleeding and superinfection, and to differentiate complicated cysts from other hemorrhagic liver lesions and biliary cystic tumors.