Hydatid cysts of the liver exert pressure on the surrounding parenchyma, and in approximately one-fourth of the cases, due to higher pressure in the cyst, the cysts eventually leak into small bile ducts or perforate into large ones. Thus the most common complication of hydatid cyst of the liver is spontaneous rupture into the biliary tract. Intrabiliary rupture occurs into the right duct in 55–60% of cases, into the left duct in 25–30% and rarely into the confluence or gall bladder.
This is a case of a hydatid cyst of the left lobe with MRCP images which ruptured spontaneously into the left hepatic duct. Thick slab and Thin Slab images are shown, with communication with hydatid cyst and left hepatic duct and intraluminal linear filling defects.