探讨电磁导航辅助内镜引导下逆行胰胆管造影术(ERCP)胆管插管在3D打印模型中应用的可行性。

采用回顾性描述性研究方法，选取2021年6月解放军总医院第一医学中心收治的2例梗阻性黄疸合并肝内外胆管扩张患者的临床资料，获取患者腹部增强CT扫描的医学数字成像和通信标准格式数据，对胆道行三维重建，将结果进行3D打印，获得胆道模型。在胆道模型内嵌入标记物，制作目标"靶点"，固定在人体腹部体模中，并在腹部体模表面贴上配准标志物，然后对体模行CT平扫，得到体模的标准三维图形(STL)格式文件。在乳头括约肌切开刀头端装置磁探头，将腹部体模表面标志物在CT扫描下获得的图像坐标，与术中获取该标志物的磁场坐标，进行术前术中配准。

配准后，乳头括约肌切开刀在进入肝总管分叉处、左肝管分支和右肝管分支前，可被实时追踪导航，精准进入目标胆管，配准效果良好。

在3D打印的胆道模型中，电磁导航系统可以很好地辅助ERCP胆管插管。

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.