A New Surgical Classification of Todani Type I and IV Choledochal Cyst

Yoon, Yoo Seok; Kim, Sun Whe; Jang, Jin Young; Choi, Min Gew; Park, Yong Hyun

Abstract

PURPOSE
After the excision of a choledochal cyst, late complications seldom develop. Herein, we propose a modified surgical classification, which allows surgeons to select an appropriate operation and minimize late postoperative complications. METHODS: A total of 90 Todani type I and IV cases were reviewed to examine the morphologic characteristics of choledochal cysts and to evaluate the clinical outcomes after cyst excision. The cysts were then reclassified based on factors determining the postoperative outcomes. RESULTS: There were 8 intrahepatic complications (4 cholangitis, 4 IHD stones) and 3 intrapancreatic complications (2 pancreatitis, 1 symptomatic remnant distal cyst). Seven of the 8 intrahepatic complications (87.5%) occurred in cases with IHD dilatation, 6 of which were associated with a ductal stricture or isolated intrahepatic cyst. Using the above factors as classification criteria, a modified surgical classification is proposed. Cases were classified as types I or IV cysts according to the presence of IHD dilatation. The type I cysts were further divided into types Ia and Ib according to the cyst multiplicity, and type IV cysts according to the pattern of continuity between the extra- and intrahepatic cyst: IHD dilatation without stricture, IVa; IHD dilatation with ductal stricture, IVb; isolated intrahepatic cyst, IVc. CONCLUSION: According to our classification, the extrahepatic approach is enough for types I, IVa and IVb to improve long-term outcome. For type IVc and some of type IVb with a stricture, where an extrahepatic approach is difficult, and hepatectomy should be combined.