Development of CT-Image Analysis System with Three-Dimensional Brain-Anatomy Data-Base

有几种类型的CT，如x射线CT、MRI和正电子CT，被用于脑部疾病的诊断。这些ct是相互补充的，对各种ct的互补数据分析将为建立新的脑部疾病诊断系统做出巨大贡献。作为该项目的第一步，该项目开发了三维脑解剖数据库和利用该数据库的结构分析算法，并证明该算法可以成功分析正常大脑的ct图像。此外，该项目开发了一种先进的算法，利用数据库从有限的二维ct横截面上的等高线重建脑解剖部分的三维结构，并通过将其应用于脑萎缩的视觉估计，证明了先进的重建算法在临床上是可行的。然而，上述结构分析算法不能应用于一个完全变形的大脑。为了解决这一问题，本项目在图像处理工作站中加入了一个可进入式ct图像分析系统作为软件。在本系统中，结构分析软件和交互软件分别用c语言和工作站特有的图形语言编写。使用交互式ct图像分析系统，操作者可以在5分钟内分析出一张ct图像。此外，本项目已初步将交互式ct图像分析系统应用于脑解剖的体积估计，初步研究表明交互式ct图像分析系统具有提供临床可用信息的潜力。

Several types of CT, such as X-Ray CT, MRI, and Positron-CT, are used for diagnoses of brain diseases. These CTs are complements each of the other, and complementary data analysis of various CTs will make a large contribution to the establishment of a new diagnostic system for brain diseases.As the first step of this, the project has developed a three-dimensional brain-anatomy data-base and a atructure-analysis algorithm utilizing the data-base, and proved that this algorithm can successfully analyze a CT-image of a normal brain. In addition, the project has developed an advanced algorithm which reconstructs three-dimensional structure of parts of brain anatomy from contour lines on a limited set of two-dimensional CT-cross section by utilizing the data-base, and demonstrated that advanced reconstruction algorithm is clinically available, through its application to visual estimation of cerebral atrophy.The above-mentioned structure-analysis algorithm, however, cannot be applied to a quite metamorphosed brain. To cope with this problem, this project has incorporated an enteractive CT-image analysis system as a software on an image-processing work-station. In this system, the structure-analysis software and the interactive software are written in the C-language and the graphics language peculiar to the workstation, respectively. An operator can analyze a CT-image within five minutes by using the interactive CT-image analysis system. Furthermore, this project has preliminarily applied the interactive CT-image analysis system to volum estimation of brain anatomies, and the preliminary investigation has demonstrated that the interactive CT-image analysis system has a potential for providing clinically available information.