Development Of Ear Microsurgery Virtual Surgery With Force Feedback

The virtual surgery is not only an important means of surgery,but also one of the main applications in the virtual reality field.In this paper,the virtual surgery technique is applied to the ear microsurgery to help the surgeon make preoperative surgical planning and do simulation training.An ear microsurgery virtual surgical system that meets the teaching guidance and simulation training needs to fully simulate the surgical procedure and ensure the interaction between the surgical operator and the model during the operation.The perspectives on the development of the ear microsurgery virtual surgery software elaborated in this paper are as followed.The ear models obtained with CT,MRI tomography and surface rendering techniques are optimized.In order to better present the virtual operation process,the compulsory double-sided display script is written to realize the backface culling.The RGBA value of the ear model's corresponding organization structure is changed by using the index to realize the semitransparent display function.By analyzing the traditional collision detection algorithm,a collision detection method is proposed of combining the multi-level bounding box tree algorithm of AABB bounding box,surrounding bounding box and OBB bounding box.With a top-down search method,it can effectively reduce the time complexity and the number of updates,ensuring the real-time of the interactive operation.In this paper,the traditional spring-mass model is optimized.A new topology is used to support the soft tissue deformation by using the support skeleton ball spring model.It has good real time and realistic sense while maintaining the model's features,further improving the immersion in the interactive process of virtual surgery.In the force feedback module,a new force feedback algorithm is proposed,which combines the area change of deforming layers and Hooke's law,and finally is transmitted by Falcon,the force feedback device.The force feedback algorithm reduces the computational complexity and meets the real-time requirements of the system.The introduction of the force feedback device increases the interactivity and fidelity of the virtual surgery.The ear microsurgery virtual surgery system developed in the paper includes the cochlear implantation surgery and the artificial stapes surgery.The key and representative operating procedures are simulated in these virtual surgeries.The system is characterized by high real-time,fun and strong robustness.It can meet surgeons' needs of preoperative guidance and simulation training.