Hepatic Hydatid Disease: Radiographics Findings

Hydatid disease (HD) is a unique parasitic disease that primarily affects the liver and is endemic in many parts of the world. There are four types of hydatid cysts (HCs) with various levels of organ involvement. All four HC types can be seen in the liver, with the right lobe being the most common site of involvement. There are many potential intrahepatic and extrahepatic complications that affect the liver and other organs. Intrahepatic complications include vascular and biliary complications and infection. With rare portal vein compression and decreased vascular supply, the involved lobe may show atrophic changes while the other lobe becomes hypertrophic. Intrahepatic biliary dilatation results from large cysts compressing intrahepatic ducts or due to cyst rupture into the biliary ducts. Cyst infection may also occur via a similar mechanism. Extrahepatic complications result from exophytic growth and hematogeneous dissemination. Exophytic growth causes migration of cysts into the lungs, mediastinum, heart and peritoneum. Hematogeneous dissemination involves all other organs.