[The value of endoscopic ultrasonography in the diagnosis and treatment of diseases at the choledocho-pancreatico-duodenal junction].

The choledocho-pancreatico-duodenal junction (CPDJ) is the core area where the biliary tract, pancreas, and duodenum converge. Diseases at this area could be difficult either to diagnose at early stage or to distinguish with each other. Endoscopic ultrasonography (EUS) can play an important role in the diagnosis of CPDJ diseases. First, EUS enables close and dynamic scanning and visualization of minor lesions and fine structures in this area. Second, EUS guided fine-needle aspiration is a significant method to obtain tissue for pathological examination. EUS is of great value especially for CPDJ tumors, minor choledocholithiasis, common bile duct and(or) pancreatic duct dilation of unknown reason, pancreatic divisum and anomalous junction of pancreaticobiliary duct. On the other hand, EUS-guided interventional techniques, including EUS-guided biliary drainage and EUS-guided gastroenterostomy, are evolving rapidly, with technical innovations in CPDJ disease treatment modality. This article introduces the value of EUS in the diagnosis and treatment of CPDJ diseases.