Study On Simulation And Training In Endoscopic Surgery

The virtual reality simulation and training system are high-level and complex combination of virtual reality technology and medicine. It is a representative application of virtual reality technique and will be widely used. At present, with development of medical technology endoscopic surgery was used more and more. This technique resulted smaller incision, less pain to patients. But this technic was complicated and needed more training. The virtual reality simulation and training technique may provide a new way in surgery learning and can offer others theoretic foundation and experience.objective:With combination of SD-rebuilding of medical images, real-time draw and soft issue model rebuilding to find out a series of universal theory and algorithm to suffice the need of capability of interact between the third dimension image and real-time force feed-back.Based on the theoretic study, in allusion to application of nasoscopic surgery (endoscopic polypectomy, endoscopic antrostomy) develop a virtual simulation training system that was applicable for yellow race.Structure of the System:In the course of simulating it consist of the following parts:1. collision detection2. deformation (or break, resect and so forth) and related compute3. feed back force computation4. 3-dimentional image drawing computationUsers operate the Sensable device in simulating surgery, the device transmit the position (the 3-dimension coordinate) to workstation to compute the collision detection. The workstation compute the outside force, distortion, feedback force out of collision detection and the physics model. Image data was computed on geometry model then was displayed the 3-dimension model on the screen. The workstation transmit the computed signal to device to produce feedback force.Function of the systemApplication of virtual reality in medicine arise from the need of visibility of 3-dimension image. Later, the data can be handle real time. And then virtual environment for pre-operation programming was developed. Virtual simulating system now have the following advantage:It can rebuilding 3-dimension model from more device (such as CT, MRI and so on).It can display the real time 3-dimension model, the scene of simulant operation.It provide virtual simulating feedback force for practice.Provide a quite real virtual model of physical reaction. With virtual appliance users can alternate with the system including the distortion of organ and feedback force.Testing results:The virtual reality simulation and training system has a simple structure, can be operate easily. It provide a relatively reality impression for nasoscopic surgery.It can play an important role in clinical training.In conclusion, we think the system has the following advantages:It is the first time to rebuild 3-dimension model suitable for yellow race from frost slice of human body in our country.It is the first system with real time feedback force for virtual simulating training.The simplified elasticity model provide virtual nasal cavity biology-physical model. By use of Finite Element Method, we study the real time elastic deformable algorithm, pre-computing algorithm. Mass-spring model enable real time feed back force. Soft tissue in nasal cavity put up relatively realistic deformation and feedback force under variant operate.We obtained living bleeding effect and high-light texture during operating by using particle technique.The 3-dimension model can be modified, so the system can run more efficiently. It is more friendly to developers and users.At present, the virtual reality simulation and training system need more study. Our system provides research foundation for further development, and step a stability pace for virtual reality technique to face practicality. With the correlative technique development, virtual reality will become more and more powerful.