【作者】 李俊波；

【导师】 许向阳；

【作者基本信息】 华中科技大学 ， 计算机软件与理论， 2007， 硕士

【摘要】 科学计算可视化是计算机图形学的一个重要研究方向,它在各个领域都有着广泛的应用。在医学领域,人们利用可视化技术由二维医学断层图像序列构建特定组织或器官的三维模型,以辅助进行临床医学诊断。科学计算可视化技术的核心是三维数据场的可视化,即三维重建。结合国家自然科学基金项目《三维肿瘤概率映射辅助前列腺活组织穿刺取样方法研究》,对医学图像三维表面重建算法进行了研究,并实现了一个医学图像三维表面可视化系统。三维表面重建可以分为基于轮廓线的表面重建和基于体素的表面重建。基于轮廓线的表面重建可以在轮廓线序列之间构建目标表面模型,采用此方法实现了前列腺的三维表面重建。其过程为先准确提取前列腺轮廓边缘,然后进行轮廓线插值,最后利用三角剖分算法构建出前列腺的三维表面模型,以辅助医生进行前列腺的活组织穿刺。移动立方体是基于体素的经典表面重建算法,此算法可在由二维医学断层图像序列构成的高密度三维数据场中提取特定组织或器官的三维表面模型,被广泛地应用于医学领域。然而,移动立方体算法存在体素搜索冗余,生成三角面片过多等不足,导致重建速度偏慢。针对这些不足,提出了一种改进算法,并在三套数据集上进行了对比实验。实验结果显示,改进算法消耗时间大为减少,满足临床医学应用中的实时性要求。三维模型在二维屏幕上显示需要经过一系列复杂的变换。OpenGL是一个性能优越的图形库,可实现三维图形的高效绘制。使用OpenGL对三维表面模型进行绘制,最后得到一个具有高真实感和操控性的三维模型,可以更好地在临床诊断中发挥作用。更多还原

【Abstract】 Scientific computation visualization is a very important research direction in computer graphics, and is used in various fields now. People use visualization technology to construct the 3D model of some tissues and organs, and use it in clinical examination. 3D reconstruction is the core of scientific computation visualization. Research is done on 3D surface reconstruction of medical images and a 3D visualization system based on the project named on 3D Probability Model Assisted Prostate Tumor Biopsy Navigation System is implemented.3D surface reconstruction can be based on contours and voxels. 3D surface reconstruction algorithms based on contours can construct 3D surface between series prostate contours. Firstly, edge detection and extraction should be done on series prostate images, and then, contours interpolation and triangles plotting must be implemented on series contours to construct the 3D surface model of prostate that can be used in the prostate tumor biopsy.Marching Cubes is a classical 3D surface reconstruction algorithm based on voxels which can extract the 3D surface model from 3D medical data. However, this algorithm search lots of blank voxels and generate too many triangles, so it is time consumption. A new algorithm for overcoming the deficiencies is presented. As the experimental result proving, the new algorithm presented accelerates the reconstruction.To display a 3D model on a 2D screen, a series of transform should be done. OpenGL is a widely used graphics interface lib that can render 3D scene efficiently. The 3D surface model rendered by OpenGL has high reality and manipulation that can play an important role in clinical diagnosis.更多还原