we use 43264 for ballon sweep removal, here is the description of the procedure:
...Endoscopic retrograde cholangiopancreatography is performed with removal of stone(s) from the biliary and/or pancreatic ducts. An endoscope is passed through the esophagus, stomach, and into the duodenum to the point where the pancreatic duct and the common bile duct meet, (the Ampulla of Vater), at the major duodenal papilla. A smaller catheter is placed through the scope, the ampulla of Vater is cannulated, and contrast dye is injected into the ducts. The common bile duct, biliary tract, gallbladder, and pancreas are visualized on x-rays, taken as soon as the dye is injected. A balloon catheter is inserted and swept down past the biliary or pancreatic duct calculus (stone). The balloon is inflated and the stone is extracted by slow withdrawal of the balloon catheter. Alternatively, a basket extraction can be performed. The basket extraction device is inserted, the calculus is trapped within the device, and the basket is then slowly withdrawn. One or more calculi may be removed during this procedure.