Table 1.

Summary of the main categories and main findings of the various liver cysts.

Category	Type
Congenital	Simple	Single or multiple; thin-walled; homogeneous; T2 hyperintensity
	Caroli’s	Central dot sign; communication with the bile duct
	Hamartoma	Multiple, small (< 1.0 cm), and homogeneous
	Ciliated	Liver segment IV subcapsular; variable content
	Polycystic liver disease	Multiple and large; increased liver volume; with or without renal cysts
Traumatic	Intrahepatic biloma	Biliary trauma or manipulation; homogeneous; without septa
	Seroma	Fluid and homogeneous collection in surgical site
	Hematoma	Trauma; hyperdensity/T1 hyperintensity; look for active bleeding
Neoplastic	Mucinous cystadenoma	Middle-aged women; multilocular; fibrous capsule; calcifications
	Cystic metastasis	Extrahepatic malignancy; multiple lesions; ring enhancement
	Cystic hepatocellular carcinoma	Cirrhosis; previous embolization; hypervascular areas; pseudocapsule
	Undifferentiated sarcoma	Children and young adults; rare; large cyst-like mass; multiple septa
Inflammatory	Pyogenic abscess	Clinical signs of infection; parietal enhancement; double-target sign; gas; perfusion disturbance
	Hydatid cyst	Positive serology; daughter cysts; honeycomb appearance; calcifications
	Amebic abscess	Endemic area; unilocular and peripheral collection (+ right liver lobe); “target” appearance; diaphragmatic rupture
	Fungal microabscess	Immunocompromised patients; multiple, small, and hypodense
Miscellaneous	Peribiliary cyst	Multiple and small, with peribiliary distribution
	Giant hemangioma with air–fluid level	Lesion > 5 cm; areas of liquefaction with an air–fluid level