Along with the popularization of chest CT screening, the incidence of early lung tumors is increasing year by year, and surgical treatment is the only means of eradication. The difficulty of surgery for this type of disease lies in the fact that due to small lesions (<1cm) and soft texture (ground-glass nodules), so surgeons can hardly to accurately determine the location of the lesion and the scope of resection during surgery. The Department of Thoracic Surgery of Shanghai Pulmonary Hospital pioneered the use of 3D printing technology to customize the preoperative localization template for small lung nodules, assisting surgeons to locate the position of lung nodules before surgery; compared with the traditional CT-guided localization technology, the 3D template preoperative localization navigation system can greatly simplify the steps of the localization operation of the lung nodules, reduce the dose of exposure to radiation, and then reduce the lung puncture-related injuries (Three- dimensional printing of navigational template), which is the most effective method to locate the position of lung nodules. dimensional printing of navigational template in localization of pulmonary nodule: a pilot study. Journal of Thoracic and Cardiovascular Surgery, 2017). Prof. Shamus R. Carr of the University of Maryland highly praised the method, saying that "this innovative approach is effective in saving cost and time for localization".

Figure 1: Principle of the 3D printed guide plate preoperative localization navigation system.

On the basis of this preliminary research, funded by Shanghai Shenkang Hospital Development Center, the Department subsequently conducted a prospective randomized controlled clinical trial, which proved that the positioning accuracy of 3D printed guide plate is not inferior to traditional CT-guided localization, and the localization time has been significantly shortened and the radiation dose has been significantly reduced, and the research results were published in the top international surgical journals in April 2019 JAMA Surgery (Accuracy of a 3-Dimensionally Printed Navigational Template for Localizing Small Pulmonary Nodules: A Noninferiority Randomized Clinical Trial), which has been positively recognized by scholars both inside and outside the country. At the same time, the research team also demonstrated the value and advantages of the application of this technology in the localization of multiple pulmonary nodules (Three-Dimensionally Printed Template for Percutaneous Localization of Multiple Lung Nodules, Annals of Thoracic Surgery, 2019).

Figure 2 Comparison of conventional CT-guided localization and 3D printed guide plate preoperative localization navigation system.

Based on the above research results, 3D printing guide plate preoperative localization system has been included into the 2019 Expert Consensus on Preoperative Assisted Localization Techniques for Small Lung Nodules, and the related products have been successfully registered with the invention patents of domestic and foreign trademark offices, and have been applied in a number of units in China.