DIRECT PERORAL CHOLANGIOSCOPE SYSTEM WITH GUIDE SHEATH

A direct peroral cholangioscope system comprises a guide sheath sized to pass through an esophagus of a patient comprising a proximal end portion, a distal end portion, and a lumen extending between the proximal end portion and the distal end portion, an endoscope comprising an elongate body extending from a proximal end to a distal end, an imaging device coupled to the elongate body proximate the distal end, and a passage extending at least partially through the elongate body and exiting at the distal end, the elongate body sized to pass through the lumen, and a tissue retrieval device configured to pass through the passage and retrieve tissue from within the patient. The guide sheath can be used to steer the endoscope through the pyloric sphincter and the sphincter of Oddi to allow the endoscope to be articulated in the common bile duct using native steering capabilities.