Abstract
With the increasing use of newer modalities such as CT cholangiography and MRCP offering an accurate delineation of the ductal anatomy of choledochal cysts, the incidence of type IV-A biliary duct cysts has increased. Although the management of the more common type I cysts is well established, that of type IV-A cysts is still controversial. The localized/unilobar variety of type IV-A cysts is a unique entity amenable to curative surgical management.
Between Jan 2000 and Jan 2005, 10 of 25 cases with choledochal cysts were diagnosed as having type IV- cysts. Four of these were localized or unilobar variants affecting only one lobe of the liver. Three cases had a left ductal involvement and one had a right ductal involvement of their intrahepatic component. We describe the presentation and curative surgical management of these patients with a unilobar variety of type IV-A cysts and discuss the management options for type IV-A cysts in the literature.
One child with previous surgical treatment for presumed type 1 cyst, diagnosed as having a type IV-A right ductal cyst complicated with liver abscess, underwent right hepatectomy, two children had a left hepatectomy and one child had a left lateral lobectomy. All four children had uncomplicated intraoperative and postoperative courses. After 4-8 years' follow-up, all are symptom-free. There were no biliary tract or hepatic abnormalities on radiological surveillance with MRCP.
In some series, the incidence of type IV-A choledochal cysts is equal to or higher than that of type 1 cysts. MRCP and intraoperative cholangiogram can help to confirm the anatomical varieties and associated ductal strictures. In the unilobar/uniductal varieties, complete cyst excision can be safely achieved in children through an additional hepatectomy/lobectomy. This can result in a curative status, leaving the child free from complications such as cholangitis, abscess, hepatolithiasis and the risk of biliary duct malignancy.