An Advanced Technology Flat-Panel Imager for Fluoroscopy

描述（由申请人提供）：有源矩阵平板成像器（AMFPI）自大约14年前首次构思以来，已经经历了广泛的研究和开发。作为这些努力的结果，这种X射线成像技术目前正被引入到各种各样的临床环境中。虽然诊断AMFPI相对于旧的传统器械具有明确的受益，但目前的间接和直接AMFPI技术存在固有的局限性，严重限制了其在荧光透视中常见的低曝光条件下的性能。 具体地，现有AMFPI设备与系统的增益相比遭受相对大的加性噪声。在提出这一建议之前进行的研究特别确定了两项创新战略，这些战略特别有希望消除这些限制。因此，在拟议的研究中要检查的问题是：“是否可行，通过开发和纳入具体的基本创新的成像设计，开发大面积，先进的技术，荧光AMFPI的性能水平匹配或超过那些在所有条件下的X射线图像增强器，并能够高放射成像性能？“为了解决这个问题，这项拨款申请提出了一项雄心勃勃的重点研究计划，以定量研究两种策略：一种涉及耦合到连续光电二极管结构的像素放大电路，用于间接检测入射辐射;另一种涉及高增益光电导转换器材料（碘化汞）用于直接检测。通过一系列的小面积和大面积的原型成像器的迭代开发，结合这些创新，这些策略的有效性将在相关的成像条件下进行定量研究。这项研究的成功完成将有助于创造一种更先进的X射线成像技术，从而实现更高性能的AMFPI系统。在所有临床条件下，这种系统将提供上级现有XRIs的空间分辨率和探测量子效率（DQE）性能，以及上级现有胶片-屏幕和计算机射线照相系统的DQE性能。展示这种性能水平的技术的发展可能对数字放射学产生深远的影响。

DESCRIPTION (provided by applicant): Active-matrix flat-panel imagers (AMFPIs) have undergone extensive research and development since their initial conception approximately 14 years ago. As a result of these efforts, this x-ray imaging technology is presently being introduced to a wide variety of clinical environments. While diagnostic AMFPIs offer definite benefits over older conventional devices, present indirect and direct AMFPI technologies suffer from inherent limitations that severely restrict their performance under the low-exposure conditions commonly encountered in fluoroscopy. Specifically, existing AMFPI devices suffer from a relatively large additive noise compared to the gain of the system. Research leading up to this proposal has specifically identified two innovative strategies that have shown particular promise for eliminating these limitations. Consequently, the question to be examined in the proposed research is: "Is it feasible, through the development and incorporation of specific fundamental innovations to imager design, to develop large area, advanced technology, fluoroscopic AMFPIs with performance levels matching or exceeding those of x-ray image intensifiers under all conditions, and capable of high radiographic imaging performance?" To address that question, this grant application proposes an ambitious, focused program of research to quantitatively investigate the two strategies: one involving in-pixel amplification circuits coupled to a continuous photodiode structure for indirect detection of the incident radiation; and the other involving a high-gain photoconductive converter material (mercuric iodide) for direct detection. Through the iterative development of a series of small and large area prototype imagers incorporating these innovations, the effectiveness of the strategies will be quantitatively examined over the relevant imaging conditions. The successful conclusion of this research will facilitate the creation of one of more highly advanced x-ray imaging technologies allowing the realization of higher performance AMFPI systems. Such systems would offer spatial resolution and detective quantum efficiency (DQE) performance superior to existing XRIIs and DQE performance superior to existing film-screen and computed radiography systems under all clinical conditions. The development of technologies exhibiting such performance levels could have a profound impact on digital radiology.