Energy Sensitive Digital Radiography

描述（由申请人提供）：该数字x线摄影项目的长期目标是减少患者剂量，并与现有技术相比，提高肿瘤和其他病变的清晰度。目前，我们还没有已知的方法可以利用典型x射线单元发出的广泛轫致辐射光谱，以及它在组织分化和增强对比度方面的潜力。一种商用GE装置通过对患者进行两次暴露，每次暴露在不同的kVp下，产生双能光子集。离子光学将开发一种现代辐射探测器来记录每个光子的能量。所需的分离成两个或多个数据集，用能量标记，然后可以由软件完成。这个算法可以根据每个病人的特点进行调整，过程类似于打开窗口。这种方法只需要一次曝光，将运动伪影减少到最低限度，并可能减少患者的曝光。核物理中的快速辐射探测器需要从多个平行通道获取数据。本项目一期将重点验证高压气体微模式探测器的有效性。这种探测器已知具有良好的物体和能量分辨率，具有良好的线性度和信噪比。由于气体吸收器较厚而产生的视差问题已基本解决。

DESCRIPTION (provided by applicant): The long-term goals of this digital radiography project is the reduction of patient dose and production of images that demonstrate increased perspicuity for neoplasms and other lesions in comparison with available techniques. Currently, there are no modalities known to us that take advantage of the broad bremmstrahlung spectrum emitted by the typical x-ray unit and it's potential for tissue differentiation and contrast enhancement. A commercially available GE unit creates dual-energy photon sets by double exposing the patient, each exposure accomplished at a different kVp. Ion Optics will develop a modern radiation detector to record the energy of each photon. The required segregation into two or more data sets, labeled by energy, can then be accomplished by software. This algorithm would be adjustable, as per the characteristics of each patient, in a process akin to windowing. This approach requires only a single exposure, reducing motion artifacts to a minimum and is likely to lead to reduced patient exposure. Required instrumentation for acquiring data from many parallel channels has been developed for fast radiation detectors in nuclear physics. Phase I of this project will concentrate on proving the efficacy of high-pressure gas micro-pattern detectors. Such detectors are known to have good object and energy resolution with excellent linearity and SNR. The problem of parallax presented by having a thick gas absorber has been largely solved.