Study On Tissue Deformation And Stress In Virtual Surgery

With the development of computer technology,Virtual Reality(VR)is approaching the stage of application gradually from theory stage which has improved our daily life.Virtual Surgery which is an important representative of Virtual Reality in medical field,it plays an irreplaceable role in doctor training,surgical planning,intraoperative warning,postoperative evaluation,remote medical treatment and so on.Deformation and stress caused by the external force can be calculated and delivered to the user by vision or other sense to make sure the user could have a more authentic experience during using the Virtual Surgery System.Although more and more research has been set up to find out a perfect algorithm that can calculate the deformation and stress caused by the external fore precisely,most of them is to deal with bone,tooth or other simple organism.There are few research on how to calculate those information of nasopharynx which is composed by nasal part,pharyngeal and paranasalsinusIn this paper 3D-model of nasopharynx is constructed through medical image processing,based on that model biomechanical simulation is proceeded through finite element analysis method(FEA).An algorithm aiming at calculating the deformation and stress of the nasopharynx caused by the external force is put forward.In 3D reconstruction step,the structure of nasopharynx and the technology used during the 3D reconstruction is introduced in this paper.Through the 3D reconstruction based on the data which is segmented from high quality CT tomography,an model that can reflects the detail of nasopharynx is got.In FEA step,the introduction of the principle of FEA and the biomechanical simulation is done.According to the characteristics of the model and simulation,the proper element is chosen.To make the model more similar to the real nasopharynx,the model is given material properties according to the anatomy knowledge.In order to get the deformation and the stress happened on the different area of nasopharynx caused by the different force,several loads has been set on some representative areas.In total,medical image processing technology and FEA is combined in this paper to create an algorithm which can improve the immersive of the VR.