Role of Imaging in Diagnosis, Predicting Biological Activity and in Treatment Plan of Hydatid Disease

Cystic Echinococcosis (CE) is a zoonotic parasitic disease caused by the larval stage of the cestode Echinococcus granulosus. Hydatid cyst is a significant universal medical problem. In human cestode involves any organ and develops to hydatid cyst. Liver is the first and most frequently involved organ as the liver is the primary filter station of portal circulation. Though hydatid disease is benign disease, traditionally surgery is the treatment of choice for complete elimination of infective focus, which is associated with considerable mortality, morbidity. Systemic chemotherapy and percutaneous drainage have evolved in the recent past as an alternative to conventional surgery. The safety and success rate of these methods is influenced by the size, stage, location of the cysts and associated complications. Benzimidazoles can be considered in multiple, small hydatid cysts, but large cysts (cysts > 6 cm), bone marrow depression, pregnancy are contraindications of pharmacotherapy. Percutaneous drainage combined with ALB is a safe and effective treatment in liver hydatid patients with a surgical contraindication and younger cysts, but the presence of certain radiological signs (pericystic ducts and exophytic components) is a contraindication to non-surgical management because of the danger of biliary obstruction. However, the surgical treatment technique also cannot be standardized, should be tailored according to the cyst relation to the Broncho, biliary, vascular structures and associated complications if any. This review will focus on role of imaging in establishing the diagnosis, in determining cyst location, size, stage of the cyst and in identifying any associated complications, so that enable the clinician to perform recommended therapeutic procedures for the different cyst types and tailor the procedure performed based on cyst relation to broncho, biliary, vascular structures and associated complications.