节点文献
在体肝脏DSA-CT图像分割配准技术的研究
Research on Techniques of Segmentation and Registration of DSA-CT Living Liver Images
【作者】 吴志坚;
【导师】 鞠颖;
【作者基本信息】 厦门大学 , 计算机系统结构, 2009, 硕士
【摘要】 虚拟肝脏手术计划系统能够提供可交互操作的平台,仿真模拟手术过程,从而有助于制定合理的个体化手术方案,可以降低损伤肝脏重要结构的危险,减少术后肝功能不全的发生率。作为虚拟肝脏手术计划系统的组成部分,本文探索的是基于计算机断层扫描(Computed Tomography,CT)图像及数字减影血管造影(Digital SubtractedAngiography,DSA)图像中的肝血管的分割配准问题。首先对CT图像的肝实质进行分割,再进一步分割出肝实质中的血管,且对DSA图像中的血管进行分割:然后,对CT血管进行三维重建,选取部分角度进行投影,将投影结果与DSA图像进行配准,并在配准结果中选取与DSA血管配准程度最高的结果,根据此结果计算出CT投影血管的肝实质轮廓,根据配准参数,将肝实质轮廓信息叠加至DSA图像中,便于医生观察DSA血管所对应的肝脏轮廓,为制定肝脏手术计划提供指导依据。本文的研究工作内容及创新主要包括以下几点:1.根据CT图像及DSA图像各自的特点,分别设计了比较适合其图像特点的分割算法。实现CT图像肝实质分割及CT图像和DSA图像的血管的分割。2.实现了CT血管图像的三维重建和所得三维血管丛模型任意角度的二维投影算法。3.为便于与DSA灌注所观察到的局部血管丛进行配准,提出了一种三维血管局部切割算法。先进行血管细化,再提取骨脊线,获得CT血管的骨脊线,得到各个节点,以各个节点为基准点,进行平面切割,从而得到局部数据。此方法有效的利用了DSA的成像原理,相比穷举法,在速度上有了很大的改善。4.设计了一种改进的配准算法,实现基于三维CT血管丛投影所得二维图像与DSA图像的二维配准算法。
【Abstract】 Virtual liver surgery Planning System can provide a platform for inter-operation, Simulate surgical procedures, thereby contribute to the development of individualized reasonable surgical program. It can reduce the risk of injury of important structures of liver; can reduce the incidence of Postoperative liver function.As an integral part of Virtual liver surgery Planning System, the exploration of this article is on of the segmentation and registration of CT liver images and DSA liver vessel image. First, segmentation of liver parenchyma in CT images, and then division of the blood vessel in the liver parenchyma, and segmentation of vessels in DSA image. Then three-dimensional reconstruction of CT vessels. Select view point to have perspective projection, registration the projection results with DSA image. Select the highest degree of matching results, calculate the edge of the liver parenchyma in accordance with the results of CT angiography projection. After registration , add the edge of liver parenchyma on DSA image. Which can facilitate Doctor observe the edge of liver parenchyma on DSA image, provide guidance to virtual liver surgery Planning System.The main contributions of this thesis are mainly lied in the following aspects:1. Aimed at the respective characteristics of CT and DSA images, corresponding algorithms were designed. The segmentation of CT liver parenchyma, CT vessels and DSA vessels, were realized.2. Three-dimensional reconstruction of CT vessel images and projection algorithm of any angle were realized.3. from The principle of imaging by CT, CT data of the blood vessels are the overall vascular. DSA can get partial vessels because of carried out for the infusion of a point. Then, before registration, Should first determine which part of that three-dimensional CT vessel for registration, for partial cutting, that is, partial cutting for three-dimensional CT vessels. 4. An improved registration algorithms were designed, the registration algorithm with DSA image and projection images of three-dimensional CT vessels were realized.