A tissue deformation method based on hyperelastic model for laparoscopic gastrectomy navigation

In laparoscopic gastrectomy navigation, a three-dimensional reconstruction model of preoperative data is used to provide real-time anatomical structure information for surgeons. However, due to the existence of tissue deformation, navigation images and laparoscopic images cannot be accurately matched. This will reduce the accuracy and security of navigation system. In this paper, a finite element deformation simulation method of hybrid hyperelastic model is proposed. Different hyperelastic models are used to establish their biomechanical models for vessels and stomach respectively, and they are connected by bonded contact method. The proposed method can accurately simulate the deformation of vessels caused by stomach pulled up. The quantitative evaluation of deformation accuracy of this method is counted by an animal experiment with pigs. The results show that this method can accurately simulate the deformation of perigastric vessels. The proposed method can improve the matching accuracy of surgical navigation and promote further research on laparoscopic gastrectomy navigation.