To explore the feasibility of electromagnetic navigation for bile duct intubation by ERCP based on a three-dimensional (3D) printing model.

The retrospective descriptive study was conducted. The clinical data of 2 patients with obstructive jaundice combined with dilation of biliary tract who were admitted to the First Medical Center of PLA General Hospital in June 2021 were collected. Medical digital imaging and standard format data of abdominal enhanced computer tomography(CT) scan were collected, 3D reconstruction of the bile duct was done and then a 3D printing biliary model was achieved. After the biliary model was embedded with the marked model to make the target, it was fixed in the human abdomen phantom.The abdomen phantom surface was pasted with marked models of registration, then the phantom was scanned by CT and STL of the phantom was obtained by segmentation. The sphincterotomy with internal electromagnetic probe was inserted into the printed hepatic ducts. The image coordinates of the registration marker target outside the abdomen phantom through the preoperative CT scan and the magnetic field coordinates of the marked target during the operation were abtained to complete operative registration.

After registration, the sphincterotomy can be tracked and navigated when it enters the common hepatic duct, the left hepatic duct and the right hepatic duct.The locations of sphincterotomy matched precisely the navigation results.

The application of electromagnetic navigation system to 3D printed biliary tract model for ERCP intubation of bile duct may bring accurate tracking effectiveness.