Dynamic Interactive Simulation Study Of Soft Tissue Cutting And Bleeding For Brain Surgery

Virtual surgery is an important application of VR technology in medical education,which can train surgeons in surgical skills,thus improving surgical proficiency and surgical success rate.Therefore,this study is of great significance.In traditional virtual surgery,deformation,cutting and bleeding are usually studied as three independent modules,resulting in poor cohesion and integration of the three,thus reducing the fidelity of virtual surgery.Secondly,the existing bleeding simulation studies do not consider the dynamic interaction process simulation of blood,and do not fully consider the physical and biological characteristics of blood,thus reducing the fidelity of blood interaction simulation.In addition,few studies have been refined operational simulation of dynamic interactive processes involving the field of brain surgery.In view of the above problems,this paper has carried out an in-depth research work on the dynamic interactive simulation of soft tissue cutting and bleeding for brain surgery,which is detailed as follows:1.In order to simulate the cutting operation in surgery in real time,a real-time interactive cutting model of soft tissue deformation based on the grid-free method is proposed.First,a trial deformation model is constructed to simulate the slight extrusion deformation between the surgical instrument and the soft tissue;second,a three-dimensional point cloud cutting model based on orthogonal plane and a cut surface rendering model based on high field grid are designed to obtain smooth and realistic incision.The experimental results show that the proposed method can simulate the cutting operation in real time.2.Considering the problem of dynamic interaction process simulation of blood,a physical interaction model of bleeding and aspiration in virtual surgery is proposed.First,the external force term in the traditional Navier-Stokes(N-S)equation is extended to add the suction force of the blood during the suction process.Secondly,a particle adsorption model was designed to realize the adsorption characteristics of blood.The experimental results show that the present method can realistically simulate the dynamic interaction process between blood and surgical instruments.3.In order to improve the rendering effect of blood,an improved hybrid depth visual rendering method(IMDR)is proposed.First,Newton’s cooling law is introduced to calculate the temperature change of blood;then,the temperature and color value of blood are related to achieve real-time update of blood color.Secondly,the smooth height field.The results show that IMDR can obtain realistic blood rendering effect and reflect the bleeding information in real time.4.To improve the real-time performance of blood rendering,a fast blood surface rendering algorithm is presented.The algorithm extracts the height information of the fluid surface,and then takes a fast method to search out the grid cells to be rendered.This method can update the grid units that need to be rendered in time,improving the rendering efficiency.Experimental results show that this method performs better in real time when simulating less bleeding.5.A brain surgery simulation training system based on force feedback equipment was built.The system can be used to demonstrate operational skills such as cutting and aspiration in surgery,and to record and evaluate the results of surgical simulation training.At the same time,the system has good scalability and can be expanded according to user needs.After test analysis,the effectiveness of the entity system is tested.