Abstract: A retrievable two piece catheter for percutaneous insertion into the common bile duct or similar vessel or canal of a patient is disclosed. The catheter is introduced as a single unit over a cannula and then formed in-situ within the duct into a T-tube configuration. Two sutures threaded through a main catheter are attached to a shorter distal auxiliary catheter, one in the center of the auxiliary catheter and one at an end thereof. After the two piece catheter has been inserted to the desired location and the cannula removed, the sutures are manipulated to maneuver the auxiliary catheter until it lies generally perpendicular to the elongated main catheter to thereby form the T-tube in fluid communication with each other. A suture-locking device provides self-retaining characteristics and the T-tube catheter can be easily retrieved, repositioned or exchanged. The T-tube catheter can be modified within a long distal limb to stent the Ampulla of Vater after balloon sphincteroplasty.