MASDA-X--AN OPTIMIZED FLAT-PANEL DIGITAL X-RAY IMAGER

这项申请提出了一项雄心勃勃的研究计划，以开发 新的实时、数字、平板成像技术，基于多 用于X射线成像的元素非晶硅探测器阵列(MASDA-X)。这个 抗辐射阵列将由二维自扫描阵列组成 2500 x 2500像素的矩阵，像素间距为100微米，提供25 x 25 cm正方形成像面积。成像器由一个X射线转换器组成， 该阵列以及相关的采集电子设备。这样的成像器提供了 相对于现有技术的重大潜在优势包括：(A) 具有即时图像捕获和呈现功能的数字射线成像 与电影银幕的曝光量相当，甚至可能要低得多 和CR系统：(B)使用紧凑型单元的实时荧光成像 胶片盒式磁带的大小，且图像质量不受 影响X射线像增强器(XRII)系统的失真和眩光； (C)曝光量和动态范围可与CR系统和大型 与胶片-屏幕系统相比；(D)空间分辨率为5 L p/mm 比现有XRII装置更好；及(E)成本低 提供低维护和高质量成像的设备。整体而言 这项研究的目标是确定平板技术是否 能够创建性能与之相当或 优于现有技术(例如胶片-屏幕和CR用于 用于透视的射线照相和XRII系统)。《公约》的具体目标 研究内容有：(L)开发成像系统的方式 分别优化射线照相和透视的成像性能。 该优化方法将涉及成像器的迭代过程 施工、性能评估、理论建模和设计 改进；(2)创建必要的采集电子设备 允许成像器的最佳信噪比性能和执行 成像仪研究；(3)彻底量化 通过测量成像器的属性，包括观察者- 独立性能变量：MTF(F)、DQE(F)和NPS(F)以确定 该成像器的信号和噪声特性与 现有技术；(4)进行初步定量检查 通过观察者依赖的成像仪的可能的临床应用 比较平板成像器和平板成像器的性能 最先进的电影屏幕、CR和XRII系统，采用各种 幻影。如果平板x射线成像仪的性能能够 可以接受，他们的潜在优势是这样的，这项技术可以 在21世纪初成为主要的放射学工具 相应地对医疗保健产生了深远的影响。拟议的研究 将回答这样的基本问题，即成像器是从这个 技术提供可与以下各项相媲美或优于 目前成熟的技术，因此有必要进行大规模投资 这将是将这些物质投入临床使用所必需的。

This application proposes an ambitious program of research to develop a new, real-time, digital, flat-panel imaging technology based upon a Multi- element Amorphous Silicon Detector Array for X-ray imaging (MASDA-X). The radiation-resistant array will consist of a 2-dimensional, self-scanning matrix of 2500 x 2500 pixels at a pixel pitch of 100 microns giving a 25 x 25 cm square imaging area. The imager consists of an x-ray converter, the array, and the associated acquisition electronics. Such imagers offer significant potential advantages over existing technologies including: (a) digital radiographic imaging with immediate image capture and presentation at equivalent or perhaps even considerably less exposure than film-screen and CR systems: (b) real-time fluoroscopic imaging with a compact unit the size of a film-cassette and with image quality free of the effects of distortion and glare that affect x-ray image intensifier (XRII) systems; (c) exposure and dynamic range comparable to that of CR systems and large compared to film-screen systems; (d) a spatial resolution of 5 l p/mm which is superior to that of existing XRII units; and (e) low cost devices offering low-maintenance and assured quality imaging. The overall objective of this research is to determine if flat-panel technology is capable of creating imaging devices with performance comparable or superior to established technologies (eg. film-screen and CR for radiography and XRII systems for fluoroscopy). The specific aims of the research are: (l) development of the imaging system in a manner so as to optimize imaging performance separately for radiography and fluoroscopy. The optimization method will involve an iterative procedure of imager construction, performance evaluation, theoretical modeling, and design improvement; (2) creation of the acquisition electronics necessary to allow optimal signal-to-noise performance of the imager and execution of the imager studies; (3) thorough quantification of the performance of the imager through measurement of its properties including observer- independent performance variables: MTF(f), DQE(f), and NPS(f) to determine how the signal and noise properties of this imager compare to those of existing technologies; (4) execution of initial quantitative examination of the possible clinical utility of the imager through observer-dependent studies comparing the performance of the flat-panel imager to that of state-of-the-art film-screen, CR, and XRII systems employing a variety of phantoms. If the performance of flat-panel x-ray imagers can be made acceptable, their potential advantages are such that this technology could become a major radiological tool early in the 21st century with a correspondingly profound impact upon health care. The proposed research will answer the essential questions of whether imagers built from this technology offer quantitative performance comparable or superior to current established technologies and thus warrant the massive investments that will be required to bring such matters into clinical use.