粒子系统左心室容积建模技术研究

【作者】 李显良；

【导师】 黄芳；

【作者基本信息】 中南大学 ， 计算机应用技术， 2008， 硕士

【摘要】 左心室容积是衡量心脏功能的重要指标之一,其精确性和可重复性对评价心脏功能具有极为重要的意义。迄今为止,国内外学者对基于医学图像的心脏建模方法进行了大量研究,但在左心室动态变形容积建模方面还未找到一种同时满足精确、稳定、高效的方法。本文将以左心室动态容积测量为目标,针对基于粒子系统的左心室变形容积建模方法进行研究,其目的是为左心室可视化直接临床诊断奠定一个良好的基础。论文深入分析了粒子系统的基本原理和应用,重点研究了粒子系统对整体物体的模拟,尤其是对动态可变形物体模拟的相关理论原理。本文提出了粒子系统左心室静态容积建模方法,研究并设计了球面增长粒子容积填充算法,以及基于三维断层数据点和三角网格表面碰撞检测的物体表面形态保持策略,建立了左心室的三维静态容积模型;本文在分析粒子系统动力学原理的基础上,提出了左心室三维变形容积建模方法,通过利用伦纳德-琼斯势能原理设计了粒子系统的内力与外力,结合粒子系统平衡策略既保持了变形物体整体性,又较好地跟踪了变形物体外部形态,同时还利用粒子的邻居搜索策略完成了算法设计与实现,建立了左心室的三维动态容积模型。仿真实验结果表明,基于粒子系统动力学原理是一种适合动态变形物体容积建模的方法,把它应用于左心室的动态模拟以及容积测算是一次新的有益尝试。更多还原

【Abstract】 The left ventricular volume is one of the important factors for functional measurement of the heart, and its accuracy and repeatability . are very meaningful for evaluating the function of the heart. Up to now, many researches have been carried out by the international scholars in cardiac modeling method based on the medical image. Yet, in the area of modeling the dynamic and deformable left ventricle, there is still not any method with precision,stabilization and high efficiency. In this paper, a deformable and dynamic left ventricular volume modeling method based on particle system is studied for the goal of measuring left ventricular volume dynamically, and its purpose is to lay a good foundation for the visualization of left ventricle in the direct clinical diagnosis.This paper analyses the principle of particle system and its applications, and investigates the simulation of particle system for the integrity objects, especially the modeling theory for the dynamic and deformable objects. A static volume modeling method based on particle system is proposed. Through researching and designing a filling volume algorithm using spherical increasing particles, as well as the strategies of keeping surface shape with collision detection for 3D computer tomography data points and triangular grid, the left ventricle 3D static volume model is reconstructed. On the basis of analysis of the theory of particle system dynamics, a 3D deformable volume modeling method of left ventricle is brought out. The internal and external forces of particle system are designed using the Leonard - Jones potential function and particle system balanced strategy. It not only holds the integrity of objects but also tracks the external morphology of the deformable objects. A volume modeling algorithm with particle neighbor searching strategy is implemented, then 3D dynamic volume model of the left ventricle is completed. The simulation results show that the theory of particle system dynamics is suitable for modeling the dynamic deformable objects. It’s a new useful attempt that the proposed method is applied to dynamic simulation and volume measuring of the left ventricle.更多还原