In the two-point method, the distal end of the drainage tube was passed over the duodenal and intestinal lumen of the common bile duct during PTCD operation. In the process of sinus dilation, guide wire was sent into the intestinal lumen through the drainage tube, and then the drainage tube was inserted into the intestinal lumen with the extract forceps under the duodenoscope in reverse order to drag the drainage tube into the intestinal lumen before being sent into the guide wire.Clamp the guide wire with the access pliers and slowly draw out the guide wire through the mouth. Expand the outer inlet skin.When the skin was 6mm, the epigastric PTCD tube was removed, the percutaneous nephrostomy dilator was placed through the guide wire, and the patient was instructed to be drawn by the assistant.The mouth end of the guide wire, the surgeon pulls the other end of the guide wire, so that the two ends of the guide wire fix in vitro to form a higher tension to Expand the skin.