Abstract
Endoscopic ultrasonography (EUS) is useful for detection of lesions, differential diagnosis, tumor staging and therapeutic procedures in patients with biliary diseases. The tumor staging for biliary cancer can be determined by the correlation between the tumor echo and the structure of the wall or the surrounding organs. As for ampullary neoplasm, EUS is useful for diagnosis of pancreatic parenchymal invasion by the tumor and tumor infiltration into the bile/pancreatic duct.
The transpapillary endoscopic approach is sometimes difficult due to ampullary invasion by the tumor or difficult biliary cannulation. Numerous studies regarding EUS-guided biliary drainage in patients with malignant biliary stricture have been reported. Moreover, EUS-guided gallbladder drainage has also been reported to be useful for the treatment of acute cholecystitis. Standardization of these techniques and development of dedicated devices optimal for EUS-guided procedures are necessary.
