Endoscopic Ultrasonograpy for Choledocholithiasis and Biliary Malignancy.

Endoscopic ultrasound (EUS) is a valuable tool in gastrointestinal endoscopy, with various applications such as diagnosis, staging, and evaluation of the pancreaticobiliary system. EUS has comparable sensitivity to magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) for detection of choledocholithiasis. EUS may be considered for evaluation for choledocholithiasis as prelude to ERCP when there is a low to intermediate suspicion for common bile duct stones or when there is an increased risk for complications from ERCP. Endosonography may also be useful in the evaluation of cholangiocarcinoma. Intraductal ultrasound within the bile duct may help differentiate malignant from benign strictures. EUS-guided fine needle aspiration can be helpful in the diagnosis of cholangiocarcinoma, especially in the region of the hilum.