The3-D Modeling For Cardiovascula Surgical Based On Virtual Reality

With the development of modern medical technology, more options forcardiovascular treatment have been available, so it is necessary to introducepre-surgical planning for individual treatment decision. Because the post-surgicalhemodynamic has great influence on the effect of treatment, the hemodynamic--optimization-based cardiovascular pre-surgical planning becomes more and morepopular. The post-surgical hemodynamic prediction is obtained mainly from thenumerical simulation of blood flow in the surgical domain, so surgical operationmodeling is needed for pre-surgical planning to optimize the surgical model, thus thehemodynamic and the treatment effect.In previous research, operation models were built with CAD technology. There isa disadvantage which the patient-specific effect is unsatisfied. In order to improve thesituation, an anatomical model sculpture system based on the virtual reality isestablished with the haptic device and OpenGL technology. This system can buildmany kinds of the operation models. The final aim of cardiovascular surgerymodeling system is to provide the data information for the doctor. Feature parametersof postoperative model can be extracted in this system. The cardiovascular surgicalmodeling includes three-dimensional reconstruction from medical images,establishment of postoperative model and extraction of feature parameters.Universal data store organization was designed for the STL and HyperSurfacefile. The model was showed in virtual environment by visual rendering and hapticrendering. According to the universal data store organization, bypass vessel model andpatch model were established and deformed for cardiovascular surgical modeling.Bezier curve was used to deform the bypass vessel model. Three control points wereused to control the deformation of model. When haptic device collided with patchmodel, the vertex in the area of patch deformation is transformed according to theposition of haptic device. The equation of Bezier curve through bypass center cangive the length of bypass vessel. The area of patch was figured out through Heronsformula.The cardiovascular surgery modeling system based on virtual reality three-dimensional technology was developed. The system included7parts, which is datastorage, model rendering, collision detection, selection and movement of the modelobject establishment of the bypass vessel and patch, deformation of model, and extraction of the model feature parameters. The CT images of a patient with heartdisease were used to3D-reconstruct digitized visual model of the cardiovascular. Theprocess of coronary artery bypass operation and patch were simulated, and the featureparameters are obtained from the system.The study on the application of the haptic device in the coronary artery bypassoperation set the foundation for the cardiovascular surgery planning system, and forsimulation of multiple modalities of operation.