Three-dimensional visualization technique compared with magnetic resonance cholangiopancreatography for evaluation of anatomic variants of pediatric congenital choledochal cysts.

OBJECTIVE: The aim of this study was to compare the application of a three-dimensional (3D) visualization technique and magnetic resonance cholangiopancreatography (MRCP) for diagnosis of pediatric congenital choledochal cysts.

METHODS: Thin slices of coronal heavily T2-weighted pulse sequences of MRI pertaining to 35 patients were retrospectively used to reconstruct 3D models. Diagnoses and variants of the biliary system were evaluated based on the 3D models and MRCP imaging. The quality of delineation of the biliary duct system and the Todani classification were evaluated. Wilcoxon and Chi-squared tests were used for statistical analysis.

RESULTS: Two cases that were diagnosed as type II congenital choledochal cysts using the 3D model were diagnosed as type I using MRCP imaging. Significant differences were observed between the two modalities with respect to the delineation of the right anterior bile duct, right posterior bile duct, and left hepatic duct. The excellent and good rates obtained with the 3D model (65.7%) were much better than that obtained with MRCP (37.1%) imaging. Two cases with accessory hepatic ducts (5.7%), one case with an accessory pancreatic duct (2.8%), and two cases with biliary strictures at the hepatic hilum (5.7%) were detected using the 3D models. In contrast, only one case with an accessory hepatic duct and one case with a biliary stricture at the hepatic hilum were detected using MRCP.

CONCLUSION: The 3D visualization technique facilitated more precise morphological evaluation of congenital choledochal cysts and provided comprehensive spatial anatomic information for diagnosis.