IMPROVEMENT OF DIGITAL ANGIOGRAPHY OF CORONARY ARTERIES

冠状动脉硬化是美国主要的死亡原因，而且它是 在很大程度上，严重的冠状动脉狭窄的存在或不存在 决定了死亡的风险。因为许多患有这种疾病的患者 疾病是无症状的，直到他们第一次发作，一种安全、廉价的 检测冠状动脉狭窄的诊断程序将是 有益的。目前进行的诊断需要一个大的 将导管插入每条动脉的开口，以便注入 不透明染料，使动脉在X光下可见。增加的 数字减影血管造影术(DSA)的对比敏感性允许 微创技术包括向主动脉根部注射，一种 更小的导管，减少了染料体积，但仅限于 成功在很大程度上是因为患者运动导致的图像质量下降 在图像采集过程中。该项目的目标是开发和测试 改进数字血管造影术的图像处理算法 冠状动脉。这些算法寻找几何变换 以便在相减之前产生两个图像的最佳配准。他们 都是基于流体基本原理的新应用 动力学，一类新的变换函数，一种新的机器方法 实地开发的搜索方法的校准和新应用 用于功能优化的人工智能。因此，这些 算法代表了图像配准的第一种方法，即 能够处理真正的三维翘曲。中国的发展和 对算法的评估将在两个特别的 设计了体模，并以一种新的方式从患者研究中获得数据。 患者研究将在血管成形术过程中获得 充气的气球和导管将作为已知的幻影动脉 尺寸。已知的位于胸部的幻影的可用性 人类的心脏跳动将第一次为 图像增强算法成功与否的定量评估 在现实的环境中。因此，拟议的研究将采用新的 一种新的图像评价技术--图像配准技术 关于数字减影中减少运动效果的问题 血管造影术。

Coronary arteriosclerosis is a leading cause of death in U.S., and it is to a large degree the presence or absence of severe coronary stenoses which determines the risk of death. Because many patients who suffer from this disease are asymptomatic until their first attack, a safe, inexpensive diagnostic procedure for detecting coronary artery stenoses would be beneficial. The diagnosis as currently carried out requires that a large catheter be inserted into the orifice of each artery in order to inject opaque dye to make the arteries visible with X rays. The increased contrast sensitivity of digital subtraction angiography (DSA) permits a less invasive technique involving an injection into the aortic root, a smaller catheter, and reduced dye volumes, but it has been of only limited success largely because of image degradation caused by patient motion during image acquisition. The aim of this project is to develop and test image processing algorithms for the improvement of digital angiography of coronary arteries. The algorithms search for a geometrical transformation to produce an optimal registration of two images before subtraction. They are based on a new application of the fundamental principles of fluid dynamics, a new class of transformation functions, a new method of machine calibration, and new application of search methods developed in the field of artifical intelligence for function optimization. As a result these algorithms represent the first approach to image registration which is capable of handling true three dimensional warping. The development and evaluation of the algorithms will be carried out on both a specially designed phantom and on data derived in a new way from patient studies. The patient studies will be acquired during angioplasty procedures in which an inflated balloon and catheter will serve as phantom arteries of known dimensions. The availability of known phantoms located in the chest on a beating human heart will provide for the first time an opportunity for quantitative evaluation of the success of the image enhancement algorithms in a realistic environment. Thus, the proposed research will employ new techniques of image registration with a new technique for image evaluation to the problem of reducing motion effects in digital subtraction angiography.