一种改进的虚拟手术中人体软组织形变方法

An Improved Method on Soft Tissue Deformation in Virtual Surgery

虚拟手术是将计算机虚拟现实技术应用于现代医学,利用医学图像数据,重构出虚拟人体软组织模型,利用触觉交互设备,在视觉和触觉上为使用者提供手术场景的模拟和仿真。其中,软组织形变的仿真和建模是虚拟手术系统核心的研究内容之一。针对虚拟手术中软组织形变仿真,提出了一种改进的弹簧—质点模型。在正四边形网格拓扑结构表面模型中,增加了结构弹簧、剪切弹簧和弯曲弹簧,使表面模型具有体模型的特征。该模型继承了传统弹簧—质点模型的建模快、原理简单、仿真速度快等优点,同时还具有控制形变区域的能力,从而提高了仿真模型的精确度,满足交互系统的真实性和稳定性需求。实验表明该方法有效增强了形变仿真的体积特征,适合于软组织形变较大时的实时仿真,满足了虚拟手术系统实时性的要求。

Virtual surgery provides the surgery simulation for users on vision and force. It applies computer virtual reality in modern medicine,uses medical image data and reconstructs virtual human soft tissue models. And the simulation and modeling of soft tissue deformation has become one of the most important research contents in virtual surgery system. An improved mass spring model is proposed in this paper for the soft tissue deformation simulation. Bending spring,shear spring and structure spring are added onto the surface model of quadrilateral mesh topological structural for soft tissues,which will make the surface model having volume feature. This model not only has the advantages of traditional spring mass model such as rapid modeling,simple principle and quick simulation,but also has the ability to control the deformation regions,which improves the accuracy of the simulation model,and meets the requirements of the realness and stability of interactive system. Experimental results show that the method is suitable for the real-time simulation of soft tissues with large deformation. It can effectively enhance the volume of deformation simulation and meet the requirements of real-time interactive systems.