Abstract:Abstract: Objective?To design and process magnetic markers for thoracoscopic esophageal tumors, and verify the feasibility and safety of magnetic tracer technique by experimental dogs.?Methods?The magnetic tracer magnets for esophageal tumor labeling and localization include tracer magnets and pursuit magnets, which are made of NdFeB material. Six healthy male Beagle dogs were made of tracer magnet clamp and fixed to esophageal hypothetical tumor by endoscopic soft tissue clip after general anesthesia. Thoracoscopy was performed 24 hours later, and the pursuit magnet was placed near the esophagus of suspected lesion through operation hole, and the tracer magnet and pursuit magnet attracted each other because of magnetic force, so as to realize the localization of the tumor during esophageal thoracoscopic surgery.?Results?The magnetic tracer magnets which can be used for the marking and localization of thoracoscopic esophageal tumors were successfully processed. 6 Beagle dogs successfully retained the tracer magnets at the assumed tumor edge of the esophagus under endoscopy, and there were no secondary injuries such as magnet or slippage and bleeding in the operation. 24 hours later, the pursuit magnet was successfully inserted under thoracoscopic surgery, and the tracer magnet and pursuit magnet were successfully sucked into each other, thus realizing the localization and recognition of esophageal tumors under thoracoscopic surgery. The whole process operated smoothly and no side damage occurred.?Conclusion?Gastroscopy combined with thoracoscopy based on magnetic tracer technique is safe and feasible, and can be applied in clinical practice.