[Endoscopy of small ducts: a luxury for a few?]

A plethora of tiny endoscopes has become available for endoscopy of the biliary tree and the main pancreatic duct. Main indications are differentiation of radiologically undetermined ductal lesions and guided lithotripsy of difficult bile duct stones. The technique of peroral and percutaneous transhepatic miniendoscopy is safe after endoscopic papillotomy or percutaneous biliary drainage. Changes of the ducts can be reliably visualized but target biopsies are required for histological confirmation of the macroscopic diagnosis. However, the technique is particularly difficult for the peroral approach, and a comparison with radiological biopsy procedures is warranted. Lithotripsy of biliary and pancreatic stones under direct visual control offers a time-saving alternative to ESWL but requires a skillful endoscopy team. In case of a failure of peroral stone removal due to a difficult anatomy, percutaneous transhepatic cholangioscopy should be considered as an effective alternative to surgery.