A patient with history of choledocholithiasis presents with elevated conjugated bilirubin. Ultrasound reveals a dilated biliary system upto the terminal pa. In case of suspicion of an ampullary obstructive calculus which of the following investigations would be most sensitive?
EUS- Most sensitive method to detect ampullary stones
PTC
MRCP
Xray abdomen
Endoscpic USG
All India exam